Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02722916 2010-11-26
Industry Industrie AJAIJ Y/MID
1IIIlIU\ 201 0111 - C~PD ~P1C D001609430 BUREAU REGIONAL OE L'OPIC
TORONTO
CPO REGIONAL OFFICE
Patent Application NOV L b 2010
of
Steve Mann
for
MUSICAL INSTRUMENT BASED ON WATER-HAMMER,
HYDRAULOPHONIC, OR HYDRAULIDIOPHONIC PERCUSSION
of which the following is a specification...
FIELD OF THE INVENTION
io The present invention pertains generally to a new kind of hydraulic
instrument, hy-
draulic user-interface, or input/output device that may be used to control
another
multimedia system or events.
BACKGROUND OF THE INVENTION
Existing musical instruments are divided into three categories: strings,
percussion,
and wind. Strings are essentially one dimensional solids (i.e. they are long
and thin,
having a relatively smal cross section). Percussion is typically a two-
dimensional (i.e.
flat, and relatively thin) or three-dimensional (hulk) solid. Wind instruments
run on
matter in its gaseous state.
More generally, various researchers have categorized all known musical instrii-
ments into five catogories: idiophones, rnembranopliones, chordophones.
aerophones,
and electrophones. This categorization scheme was devised to categorize all
possible
musical instruments either known or to be made in the future. This system
originated
thousands of years ago, was adopted by Victor-Charles MMllahillon, and then
further
refined by Hornbostel and Sachs, and is often referred to as the Hornbostel
Sachs
Musical Instrument Classification Scheme.
The first three categories refer to solid matter, in three, two. and one
dimension,
i.e. idiophones make sound from bulk (3d) solid matter. Membranophones make
sound from membranes (flat thin, essentially 2 dimensional solid matter).
Chordo-
phones make sound from stings which are essentially one dimensional solid
matter.
Another state-of-matter, namely liquid, has found relevance in musical instru-
rnents. For example, the ancient Greeks and Romans used water as a supply of
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power, in order to blow air into organ pipes. These ancient instruments like
the "wa-
ter organ" or "hy draulis" used water as a power source. or as a means to
store energy,
which was then used to push wind through organ pipes.
In a similar way, modern church organs are examples of water organs because
they
use hydro-electricity (electricity that is generated by a waterfall) as a
source of power
to run the electric motor that powers the blower. which blows the wind (air)
into the
pipes to make the sound.
Sounds can also be produced underwater. For example, municipal swimming
baths, various public and private pools, and the like, often have underwater
loud-
to speakers so that music can be played for people to hear underwater. This
also fa-
cilitates safety, so that ainiouncements over the Public Address (PA) system
can be
heard underwater.
Some animals such as dolphins and porpoises can make sounds underwater. They
do this by having air pockets in which they make sound in air, which then is
audible
underwater.
Previously I invented a musical instrument that I call a hydraulophone in
which
sound is produced and/or controlled by vibrations in liquid matter. Typically
the
hydraulic fluid is water, and the instrument typically comprises 12 finger
holes along
the length of a pipe that resembles a giant Irish tin-whistle or recorder-
flute. Water
emerges from the 12 finger holes, and the instrument is played by inserting
one or
more fingers into one or more of the finger holes to stop or partially stop
water from
emerging. Blocking the water produces a gentle soothing organ-like sound or a
flute-
like sound. Each finger hole corresponds to it note on a natural musical
scale, and
chords may be played by blocking the water from coining out of more than one
hole
simultaneously. See, for example; http://FUNtain.ca
See also my U.S. Patent 7,551,161, and associated priority documents, such as,
for example, Canadian Patent 2499784. Dec 30, 2004.
Due to its gentle soothing sound and experientiality, the hydraulophone has
found
many uses in wellness centres, water therapy, rehabilitation, and the like,
and its
spirtually uplifting quality has been realized in its use as the organ for
church services,
concerts, playing hymns, and the like.
Its ability to smoothly vary a sound sculpture inakes it useful for motion
picture
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sound tracks, and as a replacement for, or use with st rings ensembles and
other fluidly
flowing sound textures.
It has also been used in live theatrical productions to provide the
acompanying
music or sound track.
The hydraulophone is also being widely used in waterparks and children's play
areas, where its slow and gently varying sound remains pleasantly soothing,
even
when children play notes at random. or play random chords and clusters.
More recently it is being adopted by rock and roll, and jazz musicians. A
common
sentiment among jazz piano players is that it would be nice if the
hydraulophone
io responded more quickly, so that it could be used for jazz funk, reggae. and
the like.
It has been said that it would be nice if the hydraulophone had the "quick
attack"
capability of behaving like a guitar or piano, in addition to its ability to
sustain notes
like an organ or violin.
SUMMARY OF THE INVENTION
The following briefly describes my new invention. The new invention is a very
fast-responding percussion-oriented hydraulophone or hydraulophone-like
instrument.
Informally and metaphorically speaking, this new invention is to a guitar or
piano,
as the original hydraulophone invention is to a pipe organ or flute.
Now that I have said how the new invention compares to earlier hydraulophones,
let inc also say how it relates to even older instruments, such as traditional
instruments
previously known throughout human history. Whereas previous musical
instruments
use solid or gas or informatics (e.g. electrophones) as the sound source, and
user
interface, the new invention makes possible new forms of sound production
and/or
user-interface possiblities using liquids, and in particular. played by
striking liquids.
One drawback of the earlier hydraulophones is that the ruggedized versions in-
stalled in children's playgrounds and waterparks tended to respond more
slowly, owing
to the need to mitigate the destructive effects of water hammer.
The new invention exploits the effects of water hammer in order to create a
dra-
matic and forceful transient response based on the immediate and powerful
forces
that liquids can create.
For example, one aspect of the invention allows an aquatic play device,
fountain,
pipe, hot tub, or the like to be equipped with a row of finger or hand holes
from
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which water emerges to form a row of water openings that can be struck or
slapped
by a user.
Inside the device, there is, in some embodiments, the capacity to hold water
in
a rigid-walled straight tube connected to each hole, and then connected to
each of
those water-holding capacities, there is an elastic tubing.
In one embodiment I used 12 rigid plastic toilet/faucet tubes, cut, to various
lengths to form a natural scale from a 220CPS (Cycles Per Second) "A" up to a
660CPS high "E" . Each rigid toilet tube was connected to an elastic hose of
equal
length. The hoses were connected to a manifold to supply water to all of them.
In one prototype embodiment, which I built into a Jacuzzi-style bath tub in my
bathroom, I used Schedule 160 stainless steel pipes. of various lengths, to
create a
natural hydraulophone scale (110 CPS "A" through 330 CPS "E" ). The lenghts of
the pipes ranged from approximately 12 inches (approx. 305cn1) for the low A
down
to approximately 4 inches (approx. 102cm) for the high "E". The very rigid
Schedule
160 pipes were supplied by elastic hoses.
In some embodiments, a one or more hydrophones (or underwater microphones)
listens to the sound made by the vibrating water. The outputs of the
hydrophones are
electrically amplified, and sometimes various auditory effects processors are
used, or
other processors are used to generate other multimedia effects, not
necessarily limited
to auditory effects.
In another embodiment of the invention, a user-interface comprises a dozen or
so
3 inch pipes (approx. 76crn in nominal diameter), of various lengths, each
connected
to an identical rubber elastic medium, each of which has a filling nipple. The
pipes
are supplied by a gentle strea.rn of water that maintains a meniscus that is
concave
downwards. The instrument is played by slapping the meniscus with the palm of
the hand. The resulting shockwaves, water-hammer. or the like, sets a column
of
water into transient disturbance such that it settles into an oscillatory
motion that
decays exponentially, like that of 'a struck string oil a piano. Oscillations
occur due
to the interaction between the capacity to hold a mass of water in the pipe,
and the
elasticity of the end cap on the bottom of each pipe.
I made another prototype from flushometer diaphragms that oscillate at a,
specific
frequency with a specific amount of water column above each one, played,
again, by
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slapping the water directly on its end point. It is possible with the
instrument to
cup the hands in various ways to bend the pitch up or down a little bit, as
well as to
attain a wide variety of different sounds from each finger or hand hole.
In another aspect of the invention a separate hydrophone is used to pick up
the
sound made by each sound-producing element. This allows, for example, separate
signal processing for each note, or separate amplification for each note so
that the
sounds can be distributed throughout a waterpark or public art installation.
In another embodiment of the invention, the entire instrument is cast from one
piece of concrete. and the elastic mechanisms consist of water reservoirs. of
cross-
io section that is significantly larger than the pipes leading from the finger
or hand
holes. In this way, the elasticity is due to the small but nonzero
compressibility of
the liquid.
In another embodiment of the invention, the elastic element consists of a
similar
large bulbous reservoir housed in an elastic material, such that a portion of
the
elasticity is due to the small but nonzero compressibility of the liquid, and
a portion
of the elasticity is due to the material housing the liquid. I made some
prototypes.
for example, from recycled plastic or glass drink bottles. Other embodiments
of the
invention are made from one large piece of material, such as a TIG (Tungsten
Intert
Gas) welded frame, from which surplus fire extinguishers are suspended. the
fire
extinguishers being cut shorter or longer and TIG welded back together, in
various
sizes. and suspended from their hydraulic+idiophonic nodal points.
Alternatively,
the entire instrument may be molded front or made of a single piece of
plastic. This
facilitates low-cost mass production.
In another aspect of the invention, notes are changed by changing the length
of
the pipes, their diameter (both of which affect the capacity) and the spring
or elastic
mechanism or the like.
In another aspect of the invention. each finger hole of the instrument leads
directly
to a column of fluid, such that pressing the finger deeper into the finger
hole shortens
the column and increases the resonant frequency of each note, thus allowing
greater
musical expressivity.
Some embodiments of the invention are entirely acoustic. Other embodiments
are merely user-interface devices. Many preferred embodiments use acoustically
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generated sounds as input to effects such as computerized processor or the
like, in
such a way that the overall instrument is not an electronic instrument but is
more
akin to an electric guitar or other acoustically-originated but electrically
amplified
instrument.
On professional hydraulophones for concert performance, the water jets are
often
arranged like the keys on a piano, and the instrument is played by pressing
down on
one or more of the water jets, one for each tone of a diatonic or chromatic
scale. In
some embodiments there is one acoustic sounding mechanism inside the
instrument
for each finger or hand hole or other user-interface port. Whenever a finger
taps on
io the water bubbling out of the UI (user interface) port, sound is generated.
A preferred embodiment of the hydraidophoiie consists of a housing that has at
least one hole in it, through which water emerges. trickles, or sits. The hole
and
the water in it comprise a user interface, and by tapping one's fingers or
palm on or
near the hole, one can intricately create sound, and expressively vary the
dynamics,
timbre, and pitch of each note.
Besides the normal way of playing music on such a water-hammer piano, the
instrument's water jets can be used simply as a user-interface and controller
for other
multimedia devices or other devices.
Multiple water-hammer instruments can be arranged in a two- dimensional array,
or in a row., to control multiple multimedia events.
Some embodiments of the water-hanmier instrument bear similarity to an
electric
guitar, in the sense that the sound is initially generated acoustically, and
then there
is electric processing, filtering, and amplification to increase the range of
sounds but
maintain a high degree of expressively and intricacy of musical nuance that
arises
from the initially natural physical acoustic sound production. As with
electric gui-
tar, the new instrument of the invention can be used with numerous effects
pedals,
computerized effects, guitar synths, hyper instruments, and the like, while
remaining
very expressive. Particularly when playing the water-hammer piano underwater,
at
high sound levels, as with an electric guitar, feedback can be used
creatively, to get
long or infinite sustain in a way that is similar to the way in which notes
can be held
for much longer on an electric guitar than is possible with an acoustic
guitar.
Some embodiments of the invention use one or more active "hydrospeakers"
(trans-
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mit hydrophones, i.e. speakers designed for use underwater) built in, in
addition to the
"receive hydrophones" (underwater microphones) of the pickup. In much of the
liter-
attire, the term "hydrophone" means a transducer that can send and receive,
whereas
similar transducers in air are described by the words "microphone" or
"speaker" for
receive and transmit, respectively. I prefer to use the tern "hydrophone" to
denote
underwater listening transducers, and "hvdrospeaker" to denote underwater
sound-
producing transducers, in order to disambiguate in applications where the
device only
sends or only receives.
The underwater hydraulophone with acoustic pickup is also useful for creative
use
of acoustic feedback, and various interesting forms of interaction with sounds
pro-
duced in the water, especially if one or more hydrospeakers ("transmit
hydrophones")
are installed inside the instrument.
In sonic embodiments the output from each microphone is run into a bandpass
filter, tuned to the frequency of the note corresponding to that particular
user interface
port.
By cascading a variety of different filterbanks. sonic embodiments achieve a
rich
and full sound that is still very expressive, but is easier to play.
When using hydrophones to listen to the sound from inside the vibrating water,
the hydrophone caii dampen the sound, so it is best to use a hydrophone of low
"dampiness", i.e. a hydrophone that doesn't rob the instrument of too much
sound.
A peizoelectric cylinder encapsulated in a sufficiently rigid polymer will
work. Prefer-
ably the polymer has an acoustic impedance similar to water, such that there
is only
one transition zone from into and out of the peizoelectric material.
Alternatively, a
graded-impedance layer of variously designed encapsulations, one on top of the
other,
may be used. In either case, loss should be avoided, and the wire to the
hydrophone
should also be selected so that its insulation is not acoustically lossy.
In some embodiments, to further increase the playability an acoustic exciter,
such
as one or more hydrospeakers, is placed inside the instrument, causing
feedback to
occur. When combined with a bank of bandpass filters, this results in a
tendency
for the instrument to favor playing at or near the center frequency of each
bandpass
filter. As a result of this feedback, the instrument becarnes alot easier to
play "on
key", but still is sufficiently expressive (i.e. there is still sufficient
ability to "bend"
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and sculpt notes).
In other embodiments a soundboard is used. The soundboard is connected to the
reservoirs. For example, the reservoirs may each comprise an Erlentneyer flask
or
flat-bottom bottle. A plastic folding table. such as the standard folding
tables sold
in home improvement centres, works quite well for this purpose. Bottles
sitting on
the table tend to radiate to the table's surface.
Alternatively, aluminum sounding plates may be TIG welded to the bottom of
each of a plurality of aluminum bottles constructed from scrap aluminum fire
extin-
guishers. The carbon dioxide and dry powder are eruptied, and the empty
canisters
io are modified into the desired size and shape. The sounding plates extend
past the
round bottonis of the variously modified fire extinguishers, and both radiate
as well
as absorb sound from the surrounding air, and conduct this sound into the
bodies of
the fire extinguisher metal, and subsequently the water contained therein.
The soundboard provides two useful functions: (1) it radiates sound from the
1s vibrations in the chamber into the surrounding air; (2) it allows sound in
the sur-
rounding air to affect the vibrating water. This second use helps when trying
to
create acoustic feedback.
The meniscus of water rests statically or emerges slowly from each mouth,
waiting
to be struck by the palm or other body part such as the foot of the user (e.g.
there
20 can be hand division like the manuals of a pipe organ and foot division in
ground
nozzles like the pedal division of a pipe organ). This ineniscusial user-
interface allows
the user to interact with water and abruptly set it iltto vibration.
Specialized embodiments of the invention for physiotherapy and wellness:
The invention may be used for water therapy, as part of therapy pools, physio-
25 therapy, music therapy and in health and wellness centres.
The invention may have a basin that captures and recirculates water emerging
or
gently brimming over each of the mouths.
The user of the invention may be seated in the basin, such as, for example, by
making the basin be a hot tub or jacuzzi or therapy pool. One or more persons
30 may communally enjoy being in the basin while one or more of the bathers
use the
apparatus of the invention.
The invention may be used for entertainrneut, relaxation, or training
exercises, or
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the like, or in a spa or aquatics facility, waterpark, or playground for
entertainment,
relaxation, exercise, or training.
The invention may include an element for providing tactile stimulation. Such
an
element is sometimes referred to herein is a tactor. As used herein, a tactor
is a type
of transducer which converts an electrical signal to a variable tactile
stimulation and
which may also he capable of converting a tactile stimulation to an electrical
signal.
The tactor may be a vibratory transmit hvdrophone in the water, or in each
mouth
of the instrument.
In some embodiments of the invention. brainwave entrainment may be used to
io create a relaxation or mediation environment. The tactor may vibrate in a
repetition
rate in the 1 to 30 CPS (Cycles Per Second) range. The actual frequency of
vibration
need not be in that range, but some aspect of the waveform such as the
repetition
rate of tone-bursts can be placed in that range for use in brainwave
entrainment.
A headband worn by the bather may thus be used to modulate the entrainment
frequency of the device when used in these kinds of physiotherapy or the like.
More generally, brainwave entrainment need not be limited to sinusouidal
signals
of pure tone., but, may instead comprise spread spectrum excitation, or other
arbitrary
periodic or quasi-periodic signals that can be worked with the equivalent of a
more
generalized lock-in amplifier.
A standard lock-in amplifier such as a Stanford Research SR510 lock in
amplifier
can be used for sinusoidal signal detection. For example, we might excite the
user at a
particular frequency and then attempt to coherently detect the existence of
that fre-
quency in the subject's brainwaves. However, a better approach is to entrain
desired
brainwave activity more generally, with an arbitrary periodic excitation, and
then
measure, more generally. the response to this very excitation, with signal
averaging,
or the like.
Tactile and audiovisual entrainment. biofeedback, or the like. are constructed
such
that thalmic stimulation of the cerebral cortex affects cortical activity, in
a frequency
range around 1 to 30 CPS over a large area of the body such as by vibratory
elements
or other tactuators in, seating, pulsating hot tub jets, as well as
audiovisual stimulus.
Television can have a sort of hypnotic effect on the watcher, thus causing
different
brain states to be reached. Similarly, a computer screen can be directed in a
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structured way, as part of a biofeedback loop, especially in the context of a
relaxation
tub, relaxation application, or for exercises for the mind and body.
Various forms of SSVEP (Steady State Visual Evoked Potentials may be displayed
on a multimedia display device, or, alternatively, upon illumination sources
in the
s finger or hand holes of the instrument, by way of illuminating each of the
water
holes separately. In this way, one or more senses can be stimulated for
brainwave
entrainment while part of an exercise or gain(, or training or relaxation
regimen is in
process.
Some embodiments of the invention may use tactile sound, so that the device is
io more than simply all input device.
Frequencies up to a couple hundred CPS may be felt by the fingers if
sufficiently
strong in their vibrations, as can be achieved by way of, for example, a
suitable
tactuator such as the Clark Synthesis AQ339 geophone or hydrophone sometimes
referred to as an "Aquasonic Underwater Speaker" , although it is more of a
geophonic
15 or hydrophonic device than a loudspeaker (i.e. it is meant to move solid
matter or
liquid matter more so than to move air).
In applications where the use is not underwater, but outdoors in light rain,
or in
a somewhat dry housing, a Clark Synthesis model AW339 will suffice.
The result is "tactile sound", i.e. a sensation of sound sent to the human
body
zo directly in liquid or solid matter, rather than through air.
In communal bathing areas like one might find at a place like Spaworld USA,
the "tactile sound" can be felt without too much disturbance to other bathers
using
adjacent therapy equipment.
In a hot tub, even a communal hot tub or spa, tactual vibration of one
individual's
25 body can be achieved without too much disturbance to others. if desired.
Baseband versus narrowband sensing:
A simple embodiment of the invention comprises a row of a dozen or so bottles
that are filled with water, by a source that slowly fills each bottle and thus
makes all
the bottles gently runneth over. Each bottle has hydrophone, such as a
Sensortech
30 model SQ34, in the bulb part of the bottle. Each hydrophone is connected to
an
amplifier input, whereupon the instrument is played by striking or tapping the
open
mouths of the bottles to make a nice pure sound which sounds similar to that
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by a Fender Rhodes electric piano (i.e. similar to the sound made by striking
a tuning
fork tuned to each note). The sound is very pure because the bottles form
Helmholtz
resonators that each tune to one and only one frequency with very little in
the way
of overtones or higher harmonics beyond the fiurdaniental.
The best way to play the instrurnent is to strike the meniscus of the water.
This
meniscusial user-interface allows for a great deal of nuance. Additionally.
the in-
strument can be played by tapping the edjes of the necks of the bottles. with
the
fingertips, in a downward motion.
An alternative form of listening device is pressure sensor or diaphragm
sensor,
io such as made from a peizoresistive diaphragm having a Wheatstone bridge,
supplied
with a power source such as, for example, a 12 volt power supply. Preferably
the 12
volt supply is center-grounded, with +6 volts going to one side of the bridge
input and
-6 volts to the other. The bridge output, is connected to a balanced XLR
microphone
plug (Switchcraft A3NI) or a balanced quarter inch plug, or an underwater
connector.
Such a pressure sensor or diapliragnr sensor is placed such that one side of
each
diaphragm listens inside each bottle, and the other side is referenced to
atmosphere.
In this way, the sound can be heard all the way down to, and including a
frequency
of 0 CPS, i.e. DC (Direct Current).
This combined "AC DC" capability means that the sensor can hear the bell-
like sound of striking the water, as well as feel the sustained pressure if
exerted
in a sustained manner. The sensed pressure can be frequency-shifted to match
the
resonance of the bottle, and in this way, hitting the water makes a chime, and
pressing
and holding down on the water makes an organ sound.
Since the diagphragm sensor can listen to AC and DC, the result is a "PIANOr-
gan" (a portmanteau of the words "piano" and -organ'"), or "guiolin" (a
"guitar" and
"organ").
The low-frequency sensing that goes right down to 0 CPS is called baseband
sensing. and the resulting signal is called a baseband signal. It is generated
by pressing
the palm down on the mouths of one of the bottles and holding it down. As long
as
you keep it held down, the pressure in the bottle remains higher than it was
before.
and the pressure sensor continues to output DC.
The sound made by striking without pressing is an AC signal that is called a
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passband or narrowband signal.
Combining the narrowband and baseband signals can work with the bottles when
fitted with a diaphragm sensor that does double duty listening to the AC and
DC
signals.
Alternatively, since many diaphragm sensors are not very sensitive, or of
limited
dynarnage range (i.e. are damaged by heavy water hammer if they are made to
sensitive), it may be preferable to use one sensor for the AC and one for DC
and thus
have a small-signal sensor and a, large-signal sensor. A suitable DC large-
signal sensor
is a diaphragm sensor or pressure sensor such as is connnonly used in process
control
systems. A suitable AC small-signal sensor is a. Sensortech model SQ34
hydrophone.
Together these two sensors, one for each bottle, will give a better result
than using
the diaphragm sensor alone.
When using bottles, the elasticity arises from the large volume of water, and
water
being slightly compressible yields when presented in a sufficiently voluminous
reser-
voir. The bottle's own elasticity may or may not also contribute, depending on
the
wall thickness of the bottle (for example, encasing the bottles in cement
makes them
follow theory better, and thus easier to compute using the standard Helmholtz
for-
mula). Additionally, backing the bottles in cement helps prevent them from
breaking
due to excess forces and transient forces. One embodiment uses variously sized
Bor-
Beaux wine bottles or Florence flasks encased completely in cement, except for
the
mouths of the bottles, each bottle having two additional holes, one for a
continuous
water supply, and another for a listening device to listen to the vibrations
in the
water itself. The Bordeaux wine bottles. or Florence flasks, or the like. may
be cut to
different lengths using a bottle cutter. and then welded together using glass
working
techniques.
Vuine bottle cutters are well known in the art. More durable bottles can be
made from stainless steel spheres TIG welded to stainless steel pipes. An easy
way
to get stainless steel spheres is to obtain floats made out of stainless
steel. These
spherical floats are readily available. and can be TIC welded to a stainless
steel pipe,
after knocking a hole in the sphere using a plasma cutter. A suitable process
for
manufacturing the hydraulophone bottle is to use a. plasma cutter, such as
Miller
Spectrum 375 X-TREME(TM), to cut a hole in a stainless steel float. A suitable
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size of float is one that is in the 3 inch (approx. 75nmi) to 9 inch (approx.
230mm)
diameter range. A pipe is then TIC welded onto the ball to make a
hydraulophone
bottle. A satisfactory welding process is the use of a Miller Dynasty 350 that
has
been modified from the standard 14 pin control connector to the 28 pill
welding
automation connector, for use with a robotic orbital welder, to automate the
process
of TIC welding the pipes onto the balls. A weld current is delivered at high
amperage
and low frequency while a 2% Thorium tungsten electrode moves toward the pipe,
and the weld current is reduced and the frequency is increased while the
electrode
moves toward the float, which is typically of thinner material.
A satisfactory size pipe is a schedule 40, size 6 (1 inch nominal, approx.
25.4mm
nominal, having approximately 1.315 inch outside diameter) pipe for some of
the
medium notes on the instrument. A size 7 or 8 pipe is suitable for the lower
notes,
and a size 5 (this is called "three quarter inch pipe" and is approximately
1.05 inches
or 26.7mm outside diamter) is suitable for the higher notes.
Alternatively. instead of using bottles for the hydraulophone pipes, the
hydraulo-
phone pipes may each be made from a rigid pipe fitted with an elastic end
medium
on the bottom of each pipe. A satisfactory clastic medium is the diaphragm
from
a Sloan Valve model LC (which stands for "Low Consumption'') flushozneter.
Thus
a very nice waterhammer piano may be constructed from a dozen or so Sloan
Valve
LC flushozneter diaphragms fitted onto the bottoms of pipes of various
lengths, the
lengths determining the notes of each of these hydraulophone pipes.
Instead of using the flushozneter diaphragms, a thin stainless steel "bender"
may
be TIG welded to the bottom of each of a plurality of stainless steel pipes to
get the
elastic medium.
A simple variation of this embodiment arises by way of using a peizoelectric
"ben-
der" transducer as the end cap for the bottoms of each of the pipes. In this
way the
bender does double-duty as both a spring and a sensor.
Alternatively, some kind of strain guage may be affixed to each pipe bottom.
Thus
the pipe bottoms themselves become diaphragm sensors.
Suppose each of a dozen pipes is fitted with a strain guauge resistance
bridge, at
its bottommost point. One input to each bridge is supplied with a voltage
supply such
as +6 volts, for example, and the other side with -6 volts. The dozen or so
pairs of
13
CA 02722916 2010-11-26
outputs are connected to instrumentation amplifiers that can listen to the
sounds of
the vibrating water as well as listen to the baseband pressure if, for
example, pressing
and holding the palm of the hand onto the mouth of the hydranlophone pipe.
Alternatively The dozen or so bridges can be matrixed in a 3 by 4 arrangement,
to use 3 of the 6 analog inputs of an Atrnel ATNIEGA48 for example. The
bridges
are supplied by voltage from output pins PB1, PB2. PB3, and PB4 of the AT-
NIEGA 48, as referred to the Atrnel ATMEGA 48 datasheet, or the pinout
diagram,
which can be obtained from Atinel Corporation or there is also a local cache
in
http://wearcam.org/ece385/a,vr/.
Were more factors are present, we simply use more pins, e.g. PBO-7 driving a 6
by 8 set of matrixed bridges into all six analog inputs provides 48 bridges,
so that we
can then have 48 hvdraulophone pipes, i.e. 48 water holes, analogous to it
piano with
48 keys.
The output of each of the 12 bridges (one for each water hole) may be
connected
directly to pins PCO-PC2 (refer again to Atrnel ATMEGA 48 datasheet for PCO,
PC1,
PC2, etc., pinout designators), for simplicity.
Preferably, though, we connect the two outputs of each bridge (i.e. left and
right)
to a differential instrument op amp (operational amplifier) and the output of
that op
amp is what is actually connected to the input pins PCO-2. Because of the
matrixing,
for the 12 diaphragm sensors, we only require 3 op amps for 12 sensors, rather
than
requiring 12 op amps.
Pressing the pahn and holding down on one of the water holes decreases the
resistance of one path of the bridge (i.e. increases the conductivity, of one
path of the
bridge thus pulling the output voltage of the bridge in one direction. The
bridges are
normally wired so that this direction results in more positive output of the
positive
output of the bridge with the other side going more negative, such that a
differential
op amp connected to the bridge output gives a higher output.
Thus pressing down on one water hole causes a measurable output for that par-
ticular corresponding bridge. that indicates pressure. Resistance bridges are
in some
ways analogous to a carbon microphone, and can "hear" sounds and other distur-
bances made in the water, in addition to slow flexing. Thus the bridges pick
up a
frequency range that goes all the way down to 0 CPS. i.e. Direct Current (DC).
In
14
CA 02722916 2010-11-26
this sense, the sound spectrum that the bridges "hear" includes the origin, in
the
frequency axis.
In addition to flexion, in some einbodiments, we have one or more AC
hydrophones
in each pipe that listen to vibrations in the water. AC hydrophones such as
the
Sensortech SQ34 tend to pick up higher frequencies better, and they can also
"listen"
and "speak" , i.e. they can create disturbances when fed with electric input.
Another
suitable hydrophone is the previously mentioned Clark Synthesis AQ339 geophone
or
hydrophone.
Terminology:
It is helpful to classify transducers according to state-of-matter in which
they
operate:
= solid: geophone;
= liquid: hydrophone;
= gas: loudspeaker or microphone:
= plasma: ionophone.
BRIEF DESCRIPTION OF THE DRAWINGS:
The invention will now be described in more detail, by way of examples which
in no way are meant to limit the scope of the invention, but, rather, these
examples
will serve to illustrate the invention with reference to the accompanying
drawings, in
which:
FIG. 1 illustrates an embodiment of the invention having a basin, heater, and
recirculating pump, suitable for being, or being installed in, a hot tub, or
the like.
FIG. 2 illustrates a bottle piano embodiment of the invention.
FIG. 3 illustrates an AC, DC (Alternating Current, Direct Current) embodiment
of the invention in which subsonic (or DC) sounds in a bottle are used to
modify the
audible sounds in the bottle.
FIG. 4 illustrates a bottle piano embodiment of the invention setup with 12
bottles on a musical scale.
FIG. 5 illustrates a tuning inethod for the bottle piano embodiment.
CA 02722916 2010-11-26
FIG. 6 illustrates an embodiment having closely spaced mouths.
FIG. 7 illustrates all embodiment where the DC channel is implemented by a
fipple circuit that is completed by the touch of a finger or the like, to a
playing
interface.
FIG. 8 illustrates an AC/DC arrangement by way of analogy to
FIG. 9 illustrates an embodiment of the invention that uses a shifterbank to
eliminate the need for the different bottle sizes, or the need for bottles
altogether.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS:
While the invention shall now be described with reference to the preferred em-
io bodiments shown in the drawings, it should be understood that the intention
is not
to limit the invention only to the particular embodiments shown but rather to
cover
all alterations, modifications and equivalent arrangements possible within the
scope
of appended claims.
In various aspects of the present invention, references to "microphone" can
mean
any device or collection of devices capable of determining pressure, or
changes in
pressure, or flow, or changes in flow, in any medium.
Likewise the term "hydrophone" describes any of a variety of pressure
transducers,
pressure sensors, or flow sensors that convert changes in hydraulic pressure
or flow to
electrical signals. Hydrophones may include differential pressure sensors, as
well as
pressure sensors that measure gauge pressure. Thus a hydrophone may have a
single
"listening" port or dual ports, one on each side of a, glass or ceramic plate,
stainless
steel diaphragm, or the like. The term "hydrophone" may also include pressure
sensors that respond only to discrete changes in pressure, such as a pressure
switch
which may be regarded as a 1-bit hydrophone. Moreover, the term "hydrophone"
can
also describe devices that only respond to changes in pressure or pressure
difference,
i.e. to devices that cannot convey a static pressure or static pressure
differences. More
particularly, the term "hydrophone" is used to describe pressure sensors that
sense
pressure or pressure changes in any frequency range whether or not the
frequency
range is within the range of human hearing, or subsonic (including all the way
down
to zero cycles per second) or ultrasonic. Similarly the term "geophone" is
used to
describe any kind of "contact microphone" or similar transducer that senses or
can
sense vibrations or pressure or pressure changes in solid matter. Thus the
terra
16
CA 02722916 2010-11-26
"geophone" describes contact microphones that work in audible frequency ranges
as
well as other pressure sensors that work in any frequency range, not just
audible
frequencies.
The terms "Earth", "NVater", "Air" and "Fire" refer to the states-of-matter.
For
example. the Classical Element indicated by the term "earth" refers to any
solid
matter. Likewise the term "water'' refers to any liquid such as wine, oil,
hydraulic
fluid, or the like. The term "hydraulic" also refers broadly to any
pressurized or
pressurizable liquid not just water. The Classical Element of "air" likewise
refers to
any gas, etc..
The method claim(s) is/are meant to be taken in the broad sense, e.g. a method
of
making music with water by filling bottles and then putting a listening device
inside
each bottle is to be taken as the same method as putting the listening device
in first
and then filling lip the bottles.
FIG. 1 illustrates an embodiment of the invention having a basin 100B, a
heater
100H, and a recirculating pump, 100P. This embodiment is suitable for being,
or
being installed in, a hot tub, or the like. Water from basin 100B is drawn
into pump
100P where it passes through heater 100H to feed manifold 10011-1, which feeds
one or
more water supply lines lO1S, 102S, ..., etc..
The one or more water supply lines feed one or more user-interfaces 101U,
1O2U,
etc., by way of one or more supply pipes 101P. 1O2P, ..., etc..
The one or niore supply pipes are typically rigid pipes, denoted by the thick
vertical lines in the drawing, because one means to make a pipe rigid is to
make it
from relatively hard and thick-walled material, such as thick-walled Type 316
stainless
steel. or the like. Plastic pipes may be used in some embodiments. if the
pipes are
thick enough, and especially if they are backed by some rigid material such as
cement,
concrete, or the like. especially in an inground pool or inground hot tub
where concerto
is typically used.
The water within the pipes 101P, 102P, ... typically has a carefully selected
mass
that is linearly proportional to the length of the pipe. The speed of sound in
water
is about four and half times faster than in air, and the instrument of the
invention
often tends to produce lower notes, so in many embodiments of the invention we
can
neglect the time it takes sound to travel front one end of pipe 101P, 102P....
to the
li
CA 02722916 2010-11-26
other, and consider the mass of water in the pipe as a single vibrating mass.
In this
case, we approximate the vibrations in the water as being uniform along the
pipes
1O1P, 102P, ....
I shall refer to the product of the density (mass per unit volume) of the
water and
the length of the pipe, divided by its cross sectional area, as "capacity" or
"capaci-
tance", and to this body of water itself as a "capacitor".
I use the terns "capacitor" as a variation Oil the forCC-currentt analog
commonly
used in control theory. For more reading on this analogy, see, for example,
Control
Systems, by Naresh K. Sinha, John Wiley & Sons, Hardcover, 488 pages, July
1995,
io ISBN-l0: 0470235160, ISBN-13: 978-0470235164. The force-current analogy
creates
an analogy between rnechancial systems and electrical systems in which
capacitance
is analogous to mass, inductance is analogous to inverse spring constant (i.e.
a coil
of wire is analogous to the coil of a spring with inductance in Henrys
equivalent to
inverse spring constant of the spring), and voltage is analogous to velocity,
etc.. Note
that this analog theory differs from an earlier analog theory of James Clerk
Maxwell
in which voltage is analogous to force and current is analogous to velocity.
Maxwell's
version is called the force-voltage analogy. One advantage of the more recent
force-
current analogy is that voltage and velocity are both across variables (e.g.
measured
across two different points, such as when you stand on a moving train and
watch
another train go by, you're measuring relative velocity, as when you put a
voltmeter
probe from one point to another point), and that current and force are both
through
variables (i.e. force and current both occur at a single point).
We use a variant of the force-current theory in which capacitance is mass
divided
by distance to the fourth exponent, rather than letting capacitance stand for
mass
alone. This proves convenient in terns of factoring in the diameter of the
user port
(pipe 1O1P or 102P, or the like).
The capacitance of the pipes IO1P, 102P, ... is thus,
1
C = l (1)
where p is the density, typically in units of ky/r11
'1.
Capacitance, C, of Equation 1 is in units of
kg
Sal
na = ky~7rrr.
2 (2)
7T 1,
18
CA 02722916 2010-11-26
When the finger holes or user-interfaces 101 U, 102U, ... are struck, touched,
pounded or slapped, the capacitance of water in the rigid pipes 101P, 102P,
... vibrates
or oscillates due to the combined effect of the capacitance as described
above, and an
elasticity, lasticity. or elastic or lastic member, such as spring lOlL, 102L,
....
In the Fig. 1, the lastic members are depicted as springs. These can take the
forms
of flexible rubber hoses, one connected to each of the pipes 101P, 102P, ....
For example, supply lines IOIS, 102S, ... can each form one of the springs
lOlL,
102L, ... if made of sufficiently suitable elastic, elastomeric. or lastic
material.
In other embodiments springs 1011, 102L, ... comprise bulbs of water. Each of
the springs is implemented as a bulb of water, wherein the compressibility
comes from
the compressibilty of the water itself.
It is interesting to note that when I was inventing the hydraulophone, many ex-
perts in fluid mechanics discouraged me by telling me it was impossible to
make an
underwater musical instrument because water is not compressible. But despite
the
,5 fact that people often refer to liquids as incompressible fluids, we should
really say
that liquids are less compressible fluids, when compared with gases. The fact
remains
that liquids are slightly compressible, i.e. there is some degree of
compressibility,
[3 = 1 /Ii which is nonzero.
In operation. the instrument of Fig. 1 presents the user with user-interfaces
1O1U,
102U. ... numbering typically 12 interface holes on a diatonic scale covering
a 1.5
octave range. In some typical embodiments there are 19, 33, or 45 user-
interface holes,
in keeping with the traditions defined by steady-state flow-based
hydraulophones,
although any number of holes from 1 and up, are possible with the invention.
In some embodiments, stemming from each hole is a meniscus 1O1M, and the
instrument presents the user with a meniscusial user interface in which the
user slaps
the meniscus to create disturbances in the water.
Slapping the entire meniscus creates an explosive water-hammer sound, whereas
hitting half or less of the rniniscus creates a softer sound because it allows
some water
to escape while being struck.
It should be noted that the instrument responds to how hard and fast it is
struck,
as does a piano, but that there are further degrees of freedom as to how the
meniscus
is struck.
19
CA 02722916 2010-11-26
For example, you can hit the whole tiring gently, or just a little bit of it
very
firmly. In both cases you can arrange it so the total sound level is identical
in terms
of how loud it sounds, but hitting it near the edge gives a more pure bell
like quality
whereas hitting it dead center and wholly gives it a more harsh and explosive
kind of
sound.
The sound in the instrument is produced bi- vibrating water. The vibrations in
the water are very forceful but travel through small displacements. Thus to
make
them audible in a large concert hall. for example, it is preferable to have
some kind
of impedance transformation, such as by way of transformers 101T, 102T, ....
The transformers 101T, 102T, ... may comprise pressure chambers similar to
those
found in an old Edison style phonograph, each supplying a horn. Thus the
instrument,
might have 12 horns, each one made specifically for a specific note. As such
the horns
may each be optimized for the particular note they are made for, such that
there is
a large horn for the lowest note and a small horn for the highest note, and
various
sizes in between.
Alternatively, transformers 101T, 102T, ... may be constructed with
hydrophones
(underwater listening devices) connected to an electric amplifier and
loudspeaker.
A satisfactory hydrophone is a Sensortech SQ34 hydrophone connected to an
audio
amplifier having a sufficiently high input impedance.
In some embodiments, it is preferable to feedback some of the electrically
amplified
signal to the springs 101L, 102L, ... to increase the sustain of the
instrument,. A foot
pedal may be supplied to dampen this feedback, and/or mechanically dampen the
springs, much like the damping pedal of a, vibraphone.
FIG. 2 illustrates an embodiment of the invention in which springs 101L, 102L.
... are bulbs of water. The water itself forms the spring. Although liquids
are often
said to be incompressible fluids (researchers often refer to gases as
compressible fluids
and liquids as incompressible fluids) there is some nonzero degree of
compressibility
that liquids posess, even though the degree of compressibility is very small.
Let the degree of compressibility of the fluid, such as water, be denoted by
C3 =
- ~l, dV/dp. We prefer to use the incompressibility which is the reciprocal of
the
compressibility: K is the incompressibility given by K = -Vdp/dV, which is
more
like the familiar "spring constant".
CA 02722916 2010-11-26
The elastic medium of Fig. 2 is specifically a bulb of liquid, and if the
walls of
the bulb are inelastic, let us denote the elasticity, lasticity, by the letter
"L", as in
elastic, or buLb:
L=V/K=Vj (3)
Let us define this value, L as being analogous to inductance. It has units of:
3 s2
(4)
kg kq
711s2
The resonant frequency of each note is given by:
1
f (5)
2~r LC
In the case of an inelastic bulb, this is approximately:
C
f 7 Vl (6)
where c is the speed of sound in the water, c A is the area of the user-
interface
or neck, l is the length of the neck. and V is the volume of the bulb.
This inelasticity can be approximated by encasing the bulbs in concrete to
make
sure they don't offer much, if any, springiness in and of themselves. In one
embod-
y invent I encased variously modified (i.e. variously sized for various notes)
Bordeaux
wine bottles in concrete, to make a set of hydraulic resonators which I
refered to
as "Nessonators""" The word Nessonator is a word I made up from the words
"Nessie" (as in the giant sea snake said to inhabit Scotland's Loch Ness) and
"res-
onance". The name "Nessie" is a trademark that I have been using for my
aquatic
to musical instrument inventions, and I have sold these under the name
"NessicT~'r"
A Nessonator (hydraulic resonator) can be made from a rigid pipe connected to
a rubber hose, or from a rigid pipe connected to an elastic bulb, or from a
rigid pipe
connected to a rigid bulb, or from a rigid pipe connected to a diaphragm. or
from a
wide variety of other means.
15 When the Nessonator is rigid, such as can be approximated from a concrete
bottle,
we get a philosophical purity in the instrument, in the sense that the sound
comes
primarily (or wholly) from vibrating water. that has very little (or no)
influence from
the materials from which the instrument is made.
21
CA 02722916 2010-11-26
I call such an embodiment a waterflute, to distinguish it from an instrument
that
makes sound from vibrating water in conjunction with vibrating solid matter.
Embodiments of my invention that use a combination of vibrating water and
vibrating solid matter might aptly be called "hydraulidiophones", a
portmanteau of
"hydraulophone" and "idiophone". In selling such instruments I use the
tradenames
"CLARINessieTM', (analogous to a clarinet which makes sound from vibrating air
in
conjunction with vibrating solid matter of a reed), and "H2OboeT` I,,,
(hydraulophones
that have more than one reed associated with each finger hole).
A 12-jet CLARINessieTM thus has 12 reeds, whereas a 12 jet H2OboeTM typically
io has 24 or 36 reeds (2 or 3 per finger hole).
When the bulbs for springs TOIL, 102L, ... are made of material that is not
rigid,
the instrument behaves partly as a waterflute, but also exhibits features
similar to
that of the CLARINessie. Embodiments of the invention can also be made from
pipes
themselves that are somewhat elastic, or from joining elastic to inelastic
pipes, or the
like.
Whether the bulb is rigid, elastic, or whether there is no bulb at all (i.e.
where
the springs are elastic disks; cylindrical slugs, rubber hoses, or otherwise,
we may
continue to use Equation 3 but with a modified value of L analogous to the
"equivalent
inductance" that defines the resonant frequency f = 2,7 117C*
_
Referring once again to Fig. 2, pump LOOP pumps water (possibly through heater
100H if present) to a. bottle supply manifold LOOM, from which supply lines
I01S,
1025.... keep the bottles of the underwater bottle organ topped up. Springs
lOlL.
102L, ... are the bulbs (bodies) of the bottles, and pipes 101P, 102P, ...
form the
necks of the bottles.
If the bottles are encased in concrete. or simply are concrete, then they can
be
suspended by any part of the bottle, typically. However, if the bulbs are
elastic, then
they should be suspended as may be achieved by grasping the bottles by their
necks,
with bottle clamps 201C, 202C.....
Clamps 201C, 202C, ... may be retort clamps, or they may be simply a means for
3o holding the bottles, such as by welding the bottle necks to a metal plate
when the
necks are made of metal.
Each bottle has a transformer 1.OIT, or 102T, or ..., positioned near the
center of
22
CA 02722916 2010-11-26
its bulb.
A non-damping bottle holder as described above, or as facilitated by other
means,
is kind of like the way a glockenspiel or rrretallophone has the metal bars or
pipes held
at the nodal points. If the bottle is in fact idiophonic, then a non-damping
bottle
holder should grasp it in such a way as to be grasping it at or near its
idiophonic
nodal points.
When the bottle is encased in concrete, just about any mounting will be a non-
damping bottle holder.
Preferably the bottles each have a bottle fill port or supply port 201S, 202S,
...
io and a listening port 201L, 202L, ....
FIG. 3 shows an AC+DC (Alternating Current-Direct Current) embodiment of
the invention in which an eLastic buLb such as spring lOlL is fitted with a
differential
diaphragm sensor hydrophone 301H. The hydrophone 301H is a differential
pressure
sensor having two ports, an acoustic transformer port 301T and an atmospheric
ref-
,s erence port 3018,. Alternatively a flow sensor, pressure switch, or flow
switch may be
used, or a combination of devices, such as a hydrophone to listen, and a flow
switch
or pressure switch to respond to changes in flow or pressure.
Consider, for the moment, a signgle diaphragm sensor for hydrophone 301H, such
as a piezoresistive pressure sensor having a thin glass diaphragm 301D fitted
with
20 piezoresistive strain guages arranged in a wheatstone bridge. The bridge is
supplied
by a 12 volt center-tapped power supply with a grounded center tap, i.e. to
supply
the bridge with 6 volts. There are four conductors in cable set or wire
301W. Wire
301WW' being a 4-conductor wire or cable assembly has two input conductors
from the
plus minus 6 volts, and two output conductors that connect to a high gain
analog
25 instrumentation amplifier 320AC. Amplifier 320AC may be capacitively
coupled, if
desired, so that a very high gain can be achieved without problems with DC
offset. It
may comprise many stages of amplification- AC coupled (i.e. capacitively
coupled).
The AC signal processing track responds to transient sounds that make the in-
strument a bottle piano, i.e. to capture the percussive effects of water
hammer. A
30 parallel processing path also makes the instrument simultaneously function
as a bot-
tle organ. Processor and amplifier 320DC capture show changes in pressure
inside
the bottle. The processor part of processor and amplifier 320DC frequency-
shifts the
23
CA 02722916 2010-11-26
DC part of the. input signal 340S from hydroplione 301H. This can be dome by a
con-
volution in the time-domain, or by a shifting in the frequency domain (i.e.
Fourier
Transform, followed by shifting samples, followed by inverse Fourier
Transform), or
the like. Alternatively, the processor part of processor and amplifier 320DC
can be
a voltage-controlled oscillator tuned to the same frequency as the resonant
frequency
of the bottle. In this way, when you press your hand on the mouth of the
bottle, and
hold while pressing down, the pressure in the bottle stays high as long as you
hold
down, and thus a tone sounds for as long as you press down on the mouth of the
bottle.
Thus the instrument behaves like a. piano and an organ at the same time.
Slapping
the mouth of the bottle with the pahn of the hand makes a percussive sound
from
resonance in the bottle. Pressing and holding makes a steady drawn out sound.
A High Dynanic Range (IIDR) signal processor 320S combines the AC ('piano-
like") and DC ("organ-like") signals 340AC and 340DC. If one of the signals
clips,
for example, it call be moderated down in its effect, as compared to the
better (i.e.
nonclipping) of the two signals.
Any number of separate signal processing pathways can be used. For example,
there can be a high gain AC path, a low gain AC path, a high gain DC path, and
a low
gain DC path, all four of which can be combined to give a high dynamic range
signal,
using HDR processing with certaintly functions as described in the IEEE
Transactions
on Image Processing, in an article entitled "Compa.rarnetric Equations'', in
volume 9,
number 8, ISSN 1057-7149, August 2000, pages 1389-1406.
In some embodiments amplifiers 320AC and 320DC are potted in resin and placed
inside the bulb together with hydrophone 30111, for 2 reasons: so that they
are (1)
close to the source, and (2) so that they are at the same temperature is
hydrophone
30111. In fact a therrnistor inside the amplifier assembly can be coupled to
hydrophone
301H for temperature compensation against drift, especially useful in
amplifier 320DC
where offset drift might otherwise push the output 320N into the supply rails
or
saturation or cutoff.
An atmospheric reference pipe 301A emerges from the bulb spring 101L of the
bottle. Wiring 301W also emerges from the bottle.
Each bottle has 4 ports:
21
CA 02722916 2010-11-26
= a wiring port 310W;
= an atmospheric reference port 310A;
= a. port for supply lines 1015, 201S, ...; and
= a port for the user-interfaces 101U. 102U.....
When I refer to "listening device" I refer to a device that may sense
quantities
ouside the range of human hearing. Much of the DC part of the signal captured
by
hydrophone 301H is subsonic. In some embodiments, instead of using one sensing
or
listening device to sense the AC and DC. we ma use separate devices. For
example,
amplifier 320AC may be supplied with an AC hydrophone such as a Sensortech
SQ34,
i0 that is not a diaphragm sensor. Processor and amplifier 320DC may be
supplied with
a separate pressure sensor, pressure switch, flow sensor, or flow switch that
senses
when a finger or hand has blocked the mouth of the bottle, and sounds,
triggers, or
shifts a steady note out signal output 320N for as long as the mouth of the
bottle's
mouth remains blocked.
We may regard the DC capabilities of the machine as an ORGAN-izer, which
takes the bottle piano and makes it work like an organ, because you can slap
the
top of the bottle's mouth with the palm of your hand and make a very ORGAN-
like
sound, like a pipe organ, that keeps on sounding for as long as you would
like.
In fact you could press a cork into the bottle's mouth, and walk away, and
leave
it for a day or two and it would still be singing when you came back, and it
would
keep singing until you pulled the cork out again.
Another embodiment, rather than separate AC and DC paths, is to have a rever-
beration unit, such as a guitar effects pedal or other revereration unit
whether it be
based on something like the SAD1024 bucket brigade Charge Coupled Device type
echo unit, or more like a digital delay or analog delay or tape loop or the
like, just
about any suitable revereration or echo unit. The reverberation unit is
connected to
the pressure sensor, so when the pressure increases. it captures and loops
whatever
sound the bottle last made or recently made.
So if you slap the bottle with your paten, it makes the sweet sound of the
bottle
piano, and the sound is captured in a loop that gets held for as long as there
is
pressure in the bottle.
CA 02722916 2010-11-26
The sound is bottled up in the bottle for as long as you like, and keeps
echoing or
reverberating until you let go, and let it escape from the bottle.
In a computerized embodiment (e.g. using a processor for the revert),, where
the
same processor "listens" (is responsive) to the bottle through AC and DC
signals of
one hydrophone, or to separate AC and DC hydrophones), this is done, using,
for
example, a delay loop or echo loop, which might itself be realized, for
example, using
a buffer, to process and transmit the sound to a sound production system such
as a
speaker and amplifier system, as follows:
1. initialize loop buffer to zero;
2. begin acquiring data froth the AC cltattnel and DC channel;
3. when DC is not present, transmit the AC signal to the destination sound pro-
duction system unaltered but also record or capture the sound into the loop
buffer as well as transmitting it;
4. when DC is present, transmit the sound from the loop buffer instead of live
from the AC channel;
5. continue acquiring the DC signal;
6. continue looping the recorded AC signal and playing it back, i.e.
transmitting
it, repeatedly to the sound production system, for as long as the DC signal is
present;
7. when the DC signal becomes absent:
(a) stop looping the AC signal (i.e. stop playing it back and transmitting it)
to the sound production systent: and
(b) restart transmission of live AC signal to the sound production system.
In some embodiments of this aspect of the invention, it is desirable to have a
more
fluidly continuous rather than abrupt transition between AC and DC modes. Thus
what I like is to be able to tap a bottle mouth and then also press down a
little while
tapping, and have a nice blend of AC and DC. In some embodiments this is
achieved
as follows:
26
CA 02722916 2010-11-26
1. initialize loop buffer to zero;
2. begin acquiring data from the AC channel and DC channel;
3. when DC is less present, transmit more of the AC signal to the destination
sound production system unaltered but also record or capture the sound into
the loop buffer as well as transmitting it;
4. when DC is more present, transmit a greater proportion of the sound from
the
loop buffer, and a lesser proportion live from the AC channel;
5. continue acquiring the DC signal;
6. continue looping the recorded AC signal and playing it back, i.e.
transmitting
io it, repeatedly to the sound production system, in proportion to the
strength of
the DC component of the signal.
Additionally, the nature of the AC sound loop can be varied in proportion to
the DC
signal.
Alternatively, the DC input can be frequency-shifted using the AC input as a
shifting signal. When I speak of DC input here. what I really mean is the
subsonic
sounds made by the water, including the static pressure (zero frequency) and
sur-
rounding low frequencies. These are not a pure Dirac Delta measure at the
origin
(f = 0), but, rather, spread about the origin with much energy at the origin
plus some
energy around the origin. This whole DC signal is then shifted up to match the
AC
signal that is centered around the resonant frequency of the bottle,
1/(2rrsgrt(LC)).
Then the two can be added together or combined in other ways, such as, for
example,
using the DC signal to control aspects of the AC signal beyond merely the
reveration
described in the algorithm above.
FIG. 4 illustrates a bottle-based embodiment of the waterhammer piano inven-
ts Lion. Twelve bottles 460 are held by their necks using bottle clamps 430
that suspend
the bottle tops through a basin 499 where they can be struck by the player.
Typically
the instrument is played by striking the meniscus of the water brimming from
the
mouths 400U. Alternatively, the index finger can be tapped downward onto the
edge
of one or more mouths 400U.
27
CA 02722916 2010-11-26
The mouths extend into the basin past a centerline 450. The centerline is the
line through the centers of each neck, at the point where it intersects the
basin, i.e.
the line that defines the boundary between the user-interface portion of the
bottle
necks, featured as protruding mouths 400U, and the part of the bottle that
hangs
down below the basin.
The apparatus looks like a vibraphone in some regards, in the way that the
pipes
hang down below an area the user interacts with. The basin 499 is generally
curved
on a 3 to 5 foot radius (approximately 1 to 2 metres radius), and the user
(i.e. the
player) stands or sits in a position that is approximately equidistant to all
of the
io mouths 400U.
Mouths 400U are user-interface ports that the player can interact with
individually
or with more than one mouth simultaneously. A utility line 490 provides
concealment
for water supply and electrical connections. There may be separate electrical
conduit
and water supply or these may be integrated. For example, a water supply may
run
in front of each bottle and an electrical conduit may run behind. These may be
styled
similarly so that the general appearance is that of a band circling around the
bottles,
either collectively, or individually, as an aesthetic that represents rings
around, or an
orbit around a planetary celestical body, or the like.
Typically line 490 is in the shape of a gentle swoosh that provides some
physical
support to the bottles, and also protects them to some degree. as well as
providing
water supply and electrical connectivity.
Inside each bottle 460 is a listening device. or listening devices. In one
embodiment
there is a Sensortech SQ34 hydrophone in each bottle, as well as a 26PCF type
pressure sensor and signal conditioner. In another embodiment the pressure
sensor is
a broadband pressure sensor that listens in both DC (i.e. low frequencies that
include
the frequency origin f = 0) and AC (i.e. high frequencies further from the
origin).
The basin is suported on legs 470. Typically the basin and overall design of
the
instrument is suggestive of the "Nessie" style hydraulophone, itself inspired,
in shape,
by the snakelike creature said to inhabit Scotland's Loch Ness.
The instrument generally has a bulbous "head" end where the lower notes
(larger
bottles) are located, and a more slender "tail" end where the high notes
(smaller
bottles) are located. The head is supported by two leg pipes, and the tail by
only
28
CA 02722916 2010-11-26
one leg pipe. This gives a total of 3 points of support. The instrument,
standing on
3 legs, is very stable even if it is not anchored to the ground.
In a typical playground or waterpark installation, the supports are anchored
in
the ground and covered by a security plate 480 which also serves as a toe
guard to
make a nice smooth surface with the ground.
Water supply comes in through one of the supports. Another serves as the
electri-
cal connectivity, and a third support acts as the water drain from the basin,
so that
a user in a wheelchair can be parked under the instrument and not get too wet
from
dripping water.
In some embodiments, the water can also just overflow from the basin 499 in a
way that is designed so that it runs off to the sides, and does not drip onto
a user
seated under the basin.
The water supply conies from underground, up one of the three legs 470. On
that
leg is a length of flexible hose 410 secured by pipe clamps 420 to the leg and
to the
water input of the utility line 490.
Hydraulophones generally keep very good time, but in exceptionally critical ap-
plications, some embodiments can be user-tuned, by way of a tuning stub 401.
Stub
401 consists of a channel insert into each bulb that allows the bulb to slide
up and
down on the neck to fine-tune the length of the neck and thus the Capacity, C
of
water in the neck. A tuning clamp 421 locks the tuning into place.
An added advantage of this arragement is that it facilitates easy cleaning of
the
bulbs should there be vandalism in the form of insertion of garbage into the
mouths,
when the instrument is installed in a public place. Clamps 421 are operable
with a
special security keyscrew mechanism, so that key holders can time the
instrument,
and clean the bulbs. Keyholders can be trusted members of the society. when
the
instrument is installed as a civic sculpture or architectural centerpiece. In
waterparks,
the keyholders can be the lifeguards or maintenance staff. In residential
units, in the
consumer market, a responsible family member may assume the role of tuning or
cleaning the instrument.
A listening device in each bulb, such as hydrophone 440 in the largest bulb,
shown
(hydrophones in each of the other bulbs are present but not shown in the
drawing,
in order to keep the drawing simple and free of clutter) has a vent 441, which
is a
29
CA 02722916 2010-11-26
reference to atmosphere. The vent can be double split so that it can serve as
or contain
the reference to atmosphere for the hydrophone as well as the water supply to
the
bulb. In this embodiment the hydrophone is a type 26PCF diaphragm sensor
having
a programmable DC-coupled amplifier and temperature compensation onboard with
an Atmel AVR, onboard with it to control it and monitor the temperature. The
AVR
is thermally bonded to the diaphragm sensor to sense its temperature and
compensate
for offset drift that otherwise plagues high-gain DC systems. The gain is high
enough
to hear small-signal sounds made in the bottle as well as sense the DC
pressure and
subsonic pressure waves in the bulb.
A connection 442 comes from each of the hydrophones and runs through the line
490 and down one of the legs 470, underground, through an underground conduit
to a dry electrical vault where there are housed 12 AC/DC processors, one for
each
hydrophone. Each processor 440P receives input from an AC channel 440AC and a
DC channel 440DC. The processed result is fed to a sound playback system such
as
a speaker system to make the instrument loud in a waterpark where there are a
lot
of screaming children and spraying water which makes it hard to hear the
natural
acoustic sound of the instrument. The electric amplification of the instrument
is
suitable for use in large rock concerts or large public demonstrations, or to
provide a
nice background sound in a waterpark where a particular child can enjoy the
feeling
zo of performing for the whole park while hitting water and having fun and
frolic. A
sound system such as a Public Address system 440PA reproduces the sound from
each
of the 12 bottles throughout the waterpark, and a portion of this signal may
also be
used as a feedback signal 440F fed back to the instrument on soundboard 440S.
The
soundingboard may be present along the bottoms of the bottles, or along any
part of
the bottles that resonates. The purpose of the sounding board feedback signal
440F
is to sustain the sound, much like the way an electric guitar feedback system
works in
a guitar such as the Moog guitar. The feedback signal goes to a feedback
transducer
440FT. A satisfactory feedback transducer is a geoplione such as a Clark
Synthesis
Part Number AW339 tactuator.
Alternatively, flat bottom bottles may be placed on a, special sounding
surface. A
satisfactory sound board is a plastic folding table. Bottles placed on such a
table have
an almost magical property when there is a speaker under the table that plays
back
CA 02722916 2010-11-26
the sound from a hydrophone in the bottle, while striking the meniscus of the
water.
The sound feeds back into the vibrations in the bottle, causing the sound to
have an
almost bell-like clarity and sustain. It sounds touch like a Fender Rhodes
piano (i.e.
the kind of piano made from an array of taming forks). To build an embodiment
of
s this aspect of the invention, you can take one or more flat bottom bottles
such as
Erlenmeyer flasks, and place them on a plastic folding table which is
basically a thin
membrane of plastic. It works best when the plastic is wet, so the bottle
bottom
makes an acoustic bond to the table. Alternatively, a sheet of glass can be
welded to
the bottom of a bottle, or an aluminum bottle can be welded to a sheet of
aluminum
io or the like. A speaker placed under the table (or better, a tactuator such
as a Clark
Synthesis Part Number AW339 can be connected directly to the table). The
output of
an amplifier supplies sound to the tactuator or speaker, and the input of the
amplifier
is connected to a, hydrophone in the bottle and the bottle is filled all the
way with
water, so it brims over a little bit. When you strike the meniscus of water,
if the gain
15 is just right on the amplifier, you get what sounds like a tuning fork, of
such pure
tone, that the sound is very remarkably beautiful and pure, even though the
bottle
itself is far from idea. In this aspect of the invention, a relatively low
quality (low
"Q") bottle can be used but the result is a very high Q peak. For example, you
can
put an array of Coke (TM) bottles on the plastic table and time everything up
right
20 and get something that sounds like a very beautiful set of tubular bells.
Then you can
play "We'd Like To Teach The World To Sing" (the Coke song) on the bottles and
it sounds like tubular bells or chimes. Alternatively you can fill up some
Budweiser
(TM) beer bottles with water, and play a Budweiser jingle on the bottle piano.
In the instrument shown in Fig 4, such sweetness of tone that results from
this
25 feedback may be controlled by a sustain pedal switch, 449. Stepping down on
pedal
449 closes the circuit to the feedback signal 440F to give that spiritual
celestial bell-
like sound. Letting up on the pedal gives a more quickly decaying sound. In
the
drawing of Fig. 4. the switch is shown in the closed (down) position. i.e.
with the
sustain on for the nice bell-like sound, in a solid line. In a (lotted line
the switch
3o position of the switch being open (pedal up) is shown.
With this pedal control, the waterhamrner piano behaves more similarly to a
reg-
ular piano with the use of the pedal. Alternatively, a pedal with a
potentiometer can
31
CA 02722916 2010-11-26
be used. For example, a standard 14-pin connector can be put on the
instrument, and
a standard Miller Elecric TIG welding control pedal, Miller Part Number
194744, can
be used, with the wiper pin to the feedback signal 440F, the top of the
potentiometer
to the output of processor 440P. and the bottom of the potentiometer to
ground.
Thus stepping down more on the pedal increases the feedback, and easing off a
little
bit reduces the feedback a little bit. Alternatively a wireless control can be
used.
FIG. 5 illustrates a tuning embodiment included in the invention. This embod-
iment comprises one or more bottles filled with water. Depicted in the Fig. 5
is a
Bordeaux wine bottle with a flat, bottom. For feedback purposes an Erlenmeyer-
i0 shaped wine bottle works even better, but the bottle shape shown in Fig. 5
comprises
a working embodiment of a tuning system, as well as a satisfactory feedback
system.
Tuning can be achieved by filling the bottle to varying degrees. to affect the
effective neck length. The water should extend into the neck to some degree in
order
to get the bottle to Nessonate (i.e. to exhibit hydraulic resonance as a,
water-based
Helmholtz resonator). As the bottle is filled more, the Nessonant frequency
decreases.
It can be tuned by filling to the correct height, and then the neck can be cut
off at
that height to get a ininuscus-based user-interface.
However, it is preferable to be able to fine tune the bottles without having
to
partially fill them, or cut the necks (or weld on more tubing to lengthen the
necks)
each time.
A sliding neck with telescoping tubing, one sliding into the other, is also
possible.
But a better approach is to simply use an insert into the neck that occupies
some
space inside the neck. This will narrow the neck and lower the pitch.
Inserting it
further (or inserting a bigger "space taker-upper") lowers the pitch further.
The space occupier in the neck reduces the sharpness of the Nessonance, so al-
ternatively, the hydrophone itself may be used as the tuning mechanism. The
reason
this makes sense is that the hydrophone has to be in there anyway, so we might
as
well use it to tune the bottle.
The setup in Fig. 5 shows the hydrophone up in the neck, in a high position
500H.
3o A mid position 500M is shown in dotted lines. A low position 500L is also
shown in
dotted lines. As the hydrophone is lowered down, the pitch rises because the
neck
becomes free of the choke-point and widens out. As the hydrophone goes down
the
32
CA 02722916 2010-11-26
pitch goes up, to a point, and then lowering the hydrophone further causes the
pitch
to fall back down again.
There is some point of maximum pitch, where the hydrophone is between the
highest and lowest points.
Tuning the bottle by raising and lowering the hydrophone is done by having it
hang by its wiring, with wire holder 500W that grabs the wire and lowers or
raises
the hydrophone in the bottle.
A satisfactory hydrophone .540 is a Sensortech SQ34. which has a relatively
high
Effective Series Capacitance (ESC) of 15nF (nano Farads), and a good
sensitivity
of approximately -200dB (snore exact figures for Serial Number 0367 of a set
of 36
Sensortech SQ34s was 15.22itF and -200.1.4(IB). The wiring 580 from the
hydrophone
540 is connected to a voltage and phase controlled preamplifier as well as a
processor
that controls the voltage and phase of the preamplifier by way of control
signal 570.
The hydrophone is connected to half of a Hosa Technology 25 foot (approx. 8
metres) gay male (i.e. male to male) balanced patch cord (i.e. TRS male on one
and and TRS male on the other end), which, when cut in half, yields two 12.5
foot
(approx. 4 metres) cables, having a shield, and a red and white wire. The cut
end is
stripped back about 12 inches (approx. 30cm) outer rubber, and back about 6
inches
(approx. 15cm) inner rubber, exposing the white wire (ring) and red (tip)
conductors.
The shield is cut off, and glue-shrieked (glue-shrink tubing, i.e. marine
grade shrink
tubing impregnated with adhesive). The white wire goes to the black hydrophone
wire and the red goes to red, using smaller glue shrink (adhesive shrink
tubing).
This connection results in a balanced quarter inch (approx. 6111111) plug that
plugs
into standard TRS (Tip Ring Sleeve) balanced quarter inch audio equipment. The
ground of the amplifier 550 is connected to the shield of the hydrophone cable
at the
plug end only (the other end is not connected) and this ground is connected to
any
nearby railings or other metal parts, if they are not already bonded to the
circuit
ground of the apparatus. Additionally the liquid in the bottle may be
grounded, if
necessary, by way of an inserted grounding connection into the bottle. All
materials
in the bottle should be of high "Q" (i.e. low dampiness) so as not to dampen
the
vibrations in the water.
Audio equipment is used to amplify the hydrophone sound and feed some of that
:33
CA 02722916 2010-11-26
sound back to the base 500B upon which the bottle(s) sit(s). Satisfactory
audio
equipment comprises a Peavy model 16FX mixer which has 12 microphone inputs
that can be used for 12 hydrophones, one in each bottle, for a 12-bottle
piano.
The output of the Peavey 16FX is connected to the input of an amplifier such
as an
AudioPro 3000 (3kW output power), split into a subwoofer such as a Yorkville
Audio
Elite SW800, and a mid cabinet such as an Elite EX401. The Peavey 16FX
together
with the AP3000 and associated electronic. crossover, and an additional
computer-
controlled preamplifier comprise amplifier 550 which amplifies the hydrophone
signal
to a, speaker or speakers that comprise feedback transducer 540FT. The use of
a
i0 computer-controlled preamplifier allows the phase and gain of the amplifier
to be
dynamically adjusted to cancel or enhance feedback, in order to control the
sustain
and to get a nice bell-like quality from a cheap and readily available
Bordeaux wine
bottle. This avoids the need for more expensive Florence flasks, and also
allows easier
modification of a set of bottles into different sizes by using a bottle cutter
to cut parts
out of the bottle and change, its size in order to make a set of 12 welded
bottles in a
musical scale.
The setup shown here in Fig. 5 is suitable for doing a large rock concert,
with a
12 bottle piano, but for a smaller demonstration of the invention, a small
backpack-
based battery operated speaker-amplifier can also be used to excite the base
500B
upon which the bottle sits. A satisfactory base for base 500B is a
Realspace(TM)
folding table, with molded plastic top, model 29Hx72Wx30D, 774491 from Office
Depot, or a "Lifetime 4 ft. Adjustable Height Folding Table", model 48x24,
with a
table top constructed of high-density polyethylene (HDPE) plastic. The base
500B is
thus the thin membrane of HDPE plastic. This behaves like the sounding board
of a
piano or violin, and conducts the sound from the bottle to the surroundings,
as well
as from the surroundings to the bottle. The table sits upon table legs that
rest upon
rubber safety tiles, such as 4inch (approx. 100mnr thick) SofSurface tiles.
Each tile
has 64 springs in it to absorb shock and isolate the surface 500B from the
ground,
so that the instrument does not pickup too much vibration from footsteps or
passing
vehicular traffic, railway cars, streetcars, or the like.
Alternatively, a bottle clamp 5,30 suspends the bottle, and a sounding plate
is used
in place of base 500B. The sounding plate is a glass membrane welded to the
bottom
34
CA 02722916 2010-11-26
of the bottle, or it can be a piece of rigid carbon fiber, kevlar, plastic, or
thin fiberglass
bonded to the bottom of bottle 560. The sounding plate or sounding board board
helps project the sound into the surrounding air, as well as helps to receive
sound
feedback from amplifier 561 by way of feedback from the ambient sound without
the
need even for explicit feedback transducer 500FT. In fact feedback transducer
500FT
can simply be the main PA system in the concert hall or venue, and it doesn't
need
to specifically be under the table or base 500B pointing up, if it is
sufficiently strong.
A processor 540P listens to the liydrophone and rides the volume gain of
amplifier
550 up and down, to produce feedback signal 540F of such strength as to
sustain feed-
io back, that is filtered through the resonance of the water with the bottle.
Optionally,
a phase adjustment is also dynamically made to track and maintain feedback.
A very light tap on the meniscus at the top of the bottle, or just a downward
tap
with the index finger on the rim of the mouth 500U, will set the resonance in
motion,
and begin a tone that can be sustained for as long as desired by way of the
feedback.
A pedal connected to processor 540P controls this feedback process so it can
range
from heavily damped to infinite sustain. A satisfactory pedal is the Miller
Electric
Part Number 194744, or any other pedal comprising essentially a potentiometer
and
or switch (or both, as is the case in the Miller pedal).
The feedback processor uses a simple algorithm to keep the feedback going, if
and
when this feedback is desired. The algorithm proceeds as follows: check pedal;
if
sustain is desired, proceed as follows:
= if pedal is depressed fully, initiate infinite sustain as follows:
- increase gain until hydroplione clipping results or is about to result (this
occurs when the hydrophone signal from the vibrating water exceeds the
range of linear input of the amplifier);
- decrease gain by a small increment to and monitor voltage drop;
- repeat adjustments in gain to maintain a steady-state tone for as long as
the pedal is depressed fully;
if pedal eases off, decrease gain to allow any sounds to die out exponen-
tially; let gain remain proportional to pedal position:
CA 02722916 2010-11-26
- if pedal eases off completely decrease gain completely (in the case of the
5-wire 14pin Miller pedal, the switch is used for this purpose, e.g. to
shutdown the sound when the pedal backs off completely).
Not all embodiments of the invention require feedback. For example. a very
nice
embodiment of the invention can simply be made from a dozen or so bottles, fed
into
an amplifier.
In some embodiments the bottles, can also be identical, e.g. made from two six-
packs of Coke bottles, and instead of having each bottle be made a different
size,
i0 they are pitch-shifted to notes on the scale. Suppose for example, we have
a dozen
identical bottles that all produce a middle "C" when struck at the top. We
simply
need to have 12 hydrophones, one in each bottle, and frequency shift the first
"C"
down to an "A", the next "C" down to a "B", leave the third "C" as is, shift
the
fourth "C" up to a "D" and so on. In this way we get the natural minor scale
that is
typical of hydralophones. i.e. A, B, C, D. E. F, G, H (high A), I, K, K, and L
(high
E).
A collection of frequency shifters arranged in this way is called a
shifterbank. Thus
the invention described here can be implemented using a number of bottles
connected
to a shifterbank.
FIG. 6 illustrates a close-fingering embodiment of the bottle piano organ, in
which
the necks 660C are curved or bent so that the bulbs 660L of the bottles 660
swing up
and away, thus allowing the finger holes (mouths of the bottles) to be
arranged more
closely together. This figure shows a top view where the player 600P stands
near
the center 600C of the radius of curvature of the finger holes (mouths 600U).
The
figure also shows a sideview of one of the bottles, the 5th bottle from the
left (the
5th lowest note), which is typically note. lE using Natural Pitch Notation.
Natural
Pitch Notation uses the number for the more significant digit and the letter
for the
less significant digit, with the more significant digit leftmost and the less
significant
digit rightmost. The rightmost digit counts in base 8 from A to G. The first
letter
of the alphabet ("A") is the lowest value for the rightmost digit, i.e. the
counting
begins with the first letter (not the third letter "C" ).
Bulbs 660L could have air trapped in them, so bleeder valves 660B allow air to
36
CA 02722916 2010-11-26
escape when they are filled with water. Valves 660B also serve to provide a
continuous
supply of water into the bottles, to keep the mouths brimming over. The mouths
600U
face upward, or approximately upward, and thus runneth over with water, to
form a
meniscus that can be struck, tapped, or touched.
FIG. 7 illustrates an embodiment where the DC channel is implemented by a
fipple or duct circuit that is completed by the touch of a. finger onto Direct
Current
(DC) mouth 700U which is located beneath the surface of some water, e.g. in a
basin
or the like. The whole bottle is submerged under the water's surface 700.
I call the mouth 700U a. Direct Current (DC) mouth because when pressed, it
io causes a, steady continuous flow of water out of languid exit port 720
formed in duct
710. The duct 710 is supplied by a pump that pumps water into its input 730
that
dissapears out-of-frame in the drawing (i.e. not shown). So long as a finger
is pressed
against mouth 700U, Water flows from left to right from input 730 through duct
710
and out port 720 to spray across the mouth of bottle 560 to make a resonant
tone
picked up by hydrophone 540.
Letting the finger off mouth 700U introduces a big leak into the duct 710
allowing
all or most of the pressure of the water from the puntp to escape out the top
of the
Bole in duct 710. The hole in the duct is mouth 700U.
Mouth 700U may extend right to the exit port 710 if desired, so that the
finger
can influence not just the amount of water flowing across the mouth 500U of
bottle
560 but also, by way of "finger embouchure" the timbre of the sound can be
changed
depending on finger position and pressure profile and pressure distribution.
The player can block mouth 700U and also strike mouth 500U. Mouth 500U is
an Alternating Current mouth because it does not sustain water flow, but
merely
introduces water flow in a transient (i.e. alternating pressure compressions
and rar-
efactions) sense.
The player can interact with these two mouths in various combinations, to
achive
an organlike sound with DC mouth 700U and a pianolike sound with AC mouth
500U.
In some embodiments mouth 700U may extend above the surface of the water, by
way of a pipe leading from the leak or hole in duct 710 right up and out of
the water.
In this way, the player can play the bottle by blocking a water jet that
appears above
the water surface.
37
CA 02722916 2010-11-26
In another embodiment there is a keyboard where pressing keys completes the
fipple circuit or duct circuit and also strikes the bottle, for the piano
organ ("pi-
anorgan") or guitar violin ("guiolin") effect, which I call the AC/DC effect.
Thus a
keyboard can be arranged so that hitting the keys "dings" the water in the
bottles
like a bell, and holding down the keys makes the water in the bottles sing.
FIG. 8 illustrates the AC/DC arrangement by way of analogy to (or even an
embodiment of the invention by) a mass, such as the mass of water in the neck
of a
bottle, or a hanging "weight", as capacitor 800C, and spring, as inductor
800L.
Attached to the mass is shown a potentiometer which is. more typically of the
to invention, rather, a Wheatstone bridge. or similar sensor 800P. The output
860 of
sensor 800P is supplied to a processor 810. A graph or plot 850 of the
waveform
of sensor output 860 as a function of time, will show an oscillatory behaviour
when
capacitor 800C is struck. If the capacitor is a mass (`weight'') suspended
from a,
spring, then striking the weight will cause this behaviour. If the capacitor
is the
water in the neck of a bottle, then striking the water at the mouth of the
bottle will
exhibit this oscillation.
In playing the instrument of the invention, some embodiments allow for an ACDC
type of interaction in which a player can strike something, to make it ding or
ring like
a bell or piano, and then the player can also grab and hold the something to
make it
sing or sustain like a violin or organ.
The situation in Fig. 8 depicts a situation in which a player strikes the mass
with an impulse to cause it to vibrate. then waits a. little while
(approximately 3
milliseconds) and then grabs the mass and pulls it downwards and holds it
down.
Equivalently it depicts a situation when a player hits the mouth of a bottle
with the
index finger, then waits 3 milliseconds, and then slaps his or her palm down
on the
open mouth of the bottle, sealing the mouth, and applying a. downward pressure
on
the water. This tirnescale is not so realistic, i.e. usually the time between
striking and
holding would be much more, but the plot tirnescale is simply chosen for
illustrative
processes.
On plot 850, the oscillations are depicted in two regimes, an AC regime 880
from
when the player taps the mass, and a DC regime 881, depicting when the player
presses and holds the mass.
38
CA 02722916 2010-11-26
It should also be noted that these two actions can happen together, i.e. the
player
can hit the mass and keep it displaced from its origin. For example, slapping
the
paten of the hand against an open bottle mouth will create a transient AC
signal of
alternating (oscillatory) pressure waves inside the bottle and also a steady-
state DC
signal resulting from an increase in the pressure inside the bottle.
The transient strike depicted in plot 850 occurs at approximately 1
millisecond
and ends at a approximately 4 milliseconds. at which time the steady state
strike
begins to take effect from 4 milliseconds onwards. The transient oscillatory
regime
is what I call the DC regime. The regime where the mass is displaced away from
its
to central resting position, 8008, is what I call the DC regime. This is where
the user
has grabbed and held it away from its central position.
To sense the DC regime, processor 810 computes an average voltage over a time
interval, to sense a sustained trend of the signal being away from the central
position,
i.e. to sense sensor output 860 being nonzero for a sustained period of time
beyond
the mere oscillations of the AC regime. Although grabbing and holding
capactior
800C will often dampen its oscillations (i.e. introduce DC will often dampen
AC),
it is certainly possible for AC and DC to co-exist. For example, slapping the
mouth
of a bottle with the palm while simultaneously holding and pressing down
tight, will
cause oscillations with a DC offset. i.e. AC and DC together at the same time.
In
other situations, the player might tap the side of the mouth with the index
finger
to make the instrument ding, like a bell, and then slide the finger over to
cover the
whole mouth and make the note begin to sing like a violin after the ding, as
depicted
in plot 850.
Another means for determining DC content is to compute a Fourier Transform
in processor 810. Typically in this embodiment, a sliding window Fourier
Transform
is computed, and subsonic components are considered DC. In this way, even if
the
sensor 800P can't sense all the way down to zero Hertz, a subsonic part of
sensor
800P's output 860 signal can be used by processor 810 to make the AC signal
sustain
longer than it would ordinarily. If the sensor can't go all the way to zero
Hertz, I
still claim as an embodiment of my invention the use of subsonic frequency
content to
modify sonic frequency content. For example, processor 810 applies retroactive
echo
or reverberation to output 860 to a degree or extent controlled by a subsonic
content
39
CA 02722916 2010-11-26
in output 860. This retroactive echo or reverb uses a delay line or other
soundstore,
and reaches back into the past to loop back whenever the output 860 deviates
from
its central rest position 800R. The more deviance from rest position 8008, the
more
strongly processor 810 reaches into the past to reverberate output 860.
In other embodiments, the subsonic (i.(,. DC) components of output 860 are
frequency-shifted to the same or similar frequency as the AC components. I
call this
the shifterbank embodiment, because there is usually a bank of frequency
shifters, one
for each capacitor inductor pair (e.g. one for each bottle). For example, in
the plot
850 we see that there are approximately ten cycles in the 3 millisecond AC
regime.
io Let us suppose, therefore, that this sound comes from a 330Hz "E" bottle.
In the shifterbank embodiment, processor 810 is progrannned to take whatever
subsonic content occurs, and shift this up to the pitch that the capacitor and
inductor
are supposed to normally resonate at. In this example, processor 810 takes any
sub-
sonic content and frequency-shifts this up to a 330Hz note (i.e. an "E"). This
can be
is performed by something as simple as a 330Hz oscillator that has a voltage
or strength
controlled by the amount of subsonic content, to something more sophisticated
such
as a bank of 15 computer controlled oscillators that accept MIDI commands such
as
channel volume. In this case one oscillator on one channel can be controlled
with
channel volume change commands issued in proportion to how much subsonic (or
20 DC) sound is present. I use sound in the broad sense, i.e. to denote
pressure at any
frequency.
In the shifterbank embodiment it is preferable to have a temperature sensor
800T
that performs temperature compensation, so that the tuning of the oscillator
matches
the resonant frequency of whatever capacitor (e.g. bottle neck) and inductor
(e.g.
25 bottle bulb) is being used.
Voltage deviance from the average, thus outputs a frequency-shifted sound to
match the resonance of the device (e.g. bottle).
The combined AC and DC signals are amplified by amplifier 898, and output by
final instrument output 899.
30 FIG. 9 illustrates a shifterbank embodiment of the invention that allows
for the
use of identical bottles for all of the different notes, or the use of open
water regions
not contained in bottles.
CA 02722916 2010-11-26
In the bottle embodiment 12 bottles 900 are used, whereas in the openwater
embodiment 12 water regions 960 are used. A dozen hydrophones, Sensortech
SQ34,
denoted in the drawing as hydrophones 940. are used to pickup the sound or
vibtations
in water each bottle 900 or region 960. The hydrophones are each connected to
a
shifterbank 930 by wires 910. The shifterbank does a frequency-shift by
convolution
with an oscillatory wave packet recorded from a high quality Florence flask
encased in
concrete. In this way, ordinary Coke (TiVI) bottles, or even just slapping
open water
in a bathtub can be made to sound like a high quality hydraulophone.
Slapping the water at the mouths of bottles 900 or in tub 950 will produce
io frequency-shifted output amplified by amplifier 998 to output signal 999.
From the foregoing description, it will thus be evident that the present
invention
provides a design for a musical instrument or other highly expressive input
device.
As various changes can be made in the above embodiments and operating methods
without departing from the spirit or scope of the invention, it is intended
that all
matter contained in the above description or shown in the accompanying
drawings
should be interpreted as illustrative and not in a limiting sense.
Variations or modifications to the design and construction of this invention,
within
the scope of the invention, may occur to those skilled in the art upon
reviewing
the disclosure herein. Such variations or modifications, if within the spirit
of this
invention, are intended to be encompassed within the scope of any claims to
patent
protection issuing upon this invention.
41
