EAAV-A, plus B+B+C
- “EAAV” is an acronym for Electro-mechanically Augmented Violin.
- “A” refers to version, in this case Version A.
- “B+B+C” stands for baritone, bass and contra-bass.
An “Augmented” Musical Instrument
Augmented musical instruments like EAAV-A, plus B+B+C are inspired by existing acoustic instruments, building upon their existing design, playing technique and performance practice, with new electronic and/or electro-mechanical vibrating elements added that extend their expressive capabilities.
“Augmented” instruments are closely related to “Actuated” instruments. See the article, Augmented and Actuated Acoustic Musical Instruments.
Both “Augmented” and “Actuated” musical instruments exist in a design space that lies between pure acoustic and electric or electronic instruments (e.g. synthesizers and violin-like MIDI control surfaces).
EAAV-A, B+B+C Consists of Three Primary Parts that Make Sound
There are many other supporting technologies utilized, which will be described later.
- EAAV-A, or the violin itself—this is the part that is played directly
This can be thought of as the user interface to a 3-part network of musical instruments.
- B+B (Baritone and Bass Unit):
- An instrument about the size of a small cello (a highly-modified acoustic bass guitar), which plays the baritone and bass ranges (down to about 40Hz)
- B+B is not played or manipulated directly, but rather reacts to a highly-processed signal from EAAV-A.
- A unique feature of the “B+B” unit is that is has 7 bass sympathetic strings.
- These sympathetic strings react to the vibration of the B+B unit, producing a kind of natural acoustic auto-accompaniment (i.e. droning chords) to whatever is played on the violin part (i.e. EAAV-A)
- C (Contra-bass Unit):
- An extremely high-quality sub-woofer that produces notes and sub-harmonics in the contra-bass range (down to about 15 Hz)
- The input to C is the processed line-out signal from B+B, on which further processing (to lower the frequency even lower and enhance the sub-harmonic overtones) is performed.
- Mounted directed behind the B+B unit with its port aimed directly at the back of the B+B unit
Some Key Points about EAAV-A, plus B+B+C
EAAV-A, plus B+B+C was invented by Dr. Don Rickert specifically as an entry in the world-renowned Margaret A. Guthman Musical Instrument Competition. Dr. Don Rickert was one of 19 semi-finalists in this premiere musical instrument design competition.
See…
- Photos of Don Rickert performing in 2013 Guthman Musical Instrument Competition
- New York Times article Finding Our Way and Inventing Musical Instruments (JASCHA HOFFMAN, Published: April 8, 2013)
- Curious Inventor Blog - 2013 Guthman Musical Instrument Competition
- 2013 Guthman Musical Instrument competition, April 11-12, to feature People's Choice Award
- Guthman Musical Instrument Competition | Atlanta Buzz
- April 11-12, Guthman Instrument Competition Peeks at Future of Music
See Video of Don Rickert's performance in the Guthman Competition on YouTube
Why? (or What is the purpose of EAAV-A?)
- With EAAV-A, the player can “dial in” the acoustic sound that he or she wants the violin to emit.
- Using the extensions to EAAV-A (the “B+B” and “C” units), the player can produce powerful notes in the alto/tenor (viola) range to notes LOWER than can be produced by a full-size contra-bass!
- Further, due to a unique feature of the “B+B” unit, bass sympathetic strings, a harmonic “basso continuo” is produced
- This can be thought of as a kind of natural acoustic auto-accompaniment to whatever is played on the violin part (i.e. EAAV-A)
EAAV-A is the only completely functional fully-augmented bowed string instrument
This claim is, of course, as far as I have been able to determine.
Partial Augmentation
Partial augmentation is possibly best described by an example. For instance, there are commercially-available electro-magnetic and electro-mechanical devices to physically enhance the sustain of an otherwise conventional guitar. Such a device, called the Sustainiac Model C is shown below.
Full Augmentation
Electro-mechanical exciters completely replace the existing primary acoustic actuation exciter of the instrument. In the case of a violin, the existing primary exciter is the bridge…but you still need a bridge! Read on.
How Full Augmentation is achieved with EAAV-AIn the case of EAAV-A, “fully augmented” means that the vibration of the strings terminate at the
bridge and do not directly produce sound from the instrument body. The bridge does NOT come in contact with the instrument body due to the use of a “cantilevered fingerboard”, which is described below. Instead, a powerful signal is sent wirelessly from the bridge to a device containing equalization controls as well as other filters such as a “notch filter”, which affects the percussiveness of the sound of the bow attacking the strings.
- The player adjusts the frequency band and other settings to obtain the desired violin sound.
- The equalizer unit then sends the processed signal wirelessly to a small amplifier mounted on
EAAV-A.
- This amplifier then “excites” an actuator transducer, which vibrates the sound plate (the violin top) appropriately, producing completely acoustic sonic output.
- See information on actuator transducers in the article, Augmented and Actuated Acoustic Musical Instruments.
Specially Carved and Graduated Instrument Top
EAAV-A’s top specifically carved and graduated to optimally distribute the powerful vibrations of the actuator transducer, which is placed in approximately the same location that the bridge would be on a regular acoustic or electric violin. It is important to note that the actuator transducer sits directly below the bridge, as described below.
Note for violin luthiers: The top graduation of much of the upper and lower bouts is based on a standard Stradivari graduation map. The entire area of the "waist" and extending into both upper and lower bouts is completely different from a Strad or Gaurneri graduation pattern. The spruce top wood in this area is much thicker and has a noticable external "bulge", which has a perfectly flattened area centered between the sound holes on which to glue the actuator transducer. This deviation from a standard violin top was derived from much formal experimentation.
Cantilevered Fingerboard
- The violin has a completely original "floating bridge" that sits on a "shelf" that is an extension of the fingerboard. This "floating bridge" arrangement, in which the bridge does not come into contact with, and is, thus, isolated from the instrument soundboard. It is called a "Cantilevered Fingerboard."
- The adjustable cantilever was designed and fabricated by Don Rickert
- The cantilever is a composite of hard maple and carbon fiber strips
- There is a slight “spring” in the cantilever.
- Result is that the instrument responds to the bow more like an acoustic violin than an electric violin
- The entire neck, fingerboard and bridge assembly is as acoustically isolated from the body as is practical.
The Bridge
EAAV-A has the first working “floating bridge”, which isolates the violin bridge physically and acoustically from the body of the instrument
This allows the acoustic body to be completed excited by an “actuator” located on the top of the violin in approximately the same location as the bridge on a standard acoustic or electric instrument. The actual bridge is made by Barberra Transducer Systems (BTS). It has 8 embedded twin transducers (essentially 16 transducers—4 for each string) in a bridge specifically designed for applications where the majority of acoustic activity is in the bridge, such as with non-chambered solid-body electric violins with negligible acoustic properties)
EAAV-A, plus B+B+C is the only fully functional multi-part augmented acoustic musical instrument
EAAV-A controls secondary and tertiary augmented instruments.
Secondary: B+B, the baritone and bass instrument
- A highly-modified (including radical changes to the internal bracing) acoustic bass guitar with 7 actuator transducers strategically placed
- 4 high-excursion “piston” type drivers, which basically hammer the sound board. Two are placed on either side of the bridge and two are placed on the upper bout on each side of the sound hole.
- 1 medium excursion transducer connected directly to the bracing plate under the bridge.
- 2 mid-bass transducers screwed into a special brace added for this purpose and into the neck block. Screwing these powerful mid-bass drivers into structural bracing distributes the low frequencies throughout the instrument body
- Three amplifiers are involved. Each transducer has its own channel.
- The inputs to the amplifiers are filtered to output various frequencies. Two channels that drive the low frequency drivers are further filtered by a device to increase sub-harmonics substantially.
- All of the above contribute to vibrating the bass sympathetic strings, tuned from D1(36.71 Hz)
to C#2 (69.30 Hz)
- Produce harmonic chords that have a bit of a organ-like sound by themselves.
- Contributes to the whole B+B instrument sounding more like a baritone and bass violas da gamba played together rather than a ‘cello
- Bass sympathetic strings are used on harp guitars of the early 20th Century (and now being revived)
- The filters
See the article, What is a filter in the context of musical instruments?
- The input is the “dry” (unmodified) signal from the piezoelectric transducers embedded in the violin bridge.
- Octaver (reduces the input signal by one octave)
- EQ unit optimized for bass frequencies
- Sub-harmonic booster
Tertiary: C, the contra-bass instrument
- The input is the line-out from one of the B+B unit amplifiers is first processed by an additional filter, which reduces the signal yet another octave and boosts the sub-harmonic overtones even more
- This basically a powered 150 watt sub-woofer capable of playing notes and sub-harmonics as low as the 15 to 20 Hz range.
Other Stuff
There are, of course, countless patch cords, wireless transmitters and receivers, mixers and signal routers involved.
