The Spectrum Piano uses a basic force of nature to make the strings of a piano vibrate. Electromagnetic flux, not hammers, drives the unique sound of the instrument. The Spectrum Piano can create many different sounds at the same time.
The name Spectrum Piano (or Spectral Piano) comes from the ability to directly access the sounds of the natural harmonics, or “spectrum” of the piano strings. This allows it to create new sounds never heard before from a speakerless acoustic instrument. Here is the first version of the instrument.
The Spectrum Piano mechanism as used for the first live performance. At this time the instrument was called the “Spectral Piano”. The Spectrum Piano mechanism can be safely moved from piano to piano.
First concert, January 2013!
The second generation (as seen in the top photo) is all brass and aluminum. Here is another closeup:
When asked to fly across the continent to perform, I created a lighter weight “portable” instrument.
How is this possible?
The hidden harmonic notes of the string
So, how does the Spectrum Piano create so many different sounds, and create high pitched sounds using low strings?
A vibrating string creates many different but related frequencies as part of the sound. This is called the “Overtone” series. These frequencies can also be considered as musical pitches, or notes. These frequencies, or notes, work well together, as they are all present inside of the sound of a single vibrating string. They are created by simultaneous vibrations of the entire string length, then by 1/2 the length, 1/3, 1/4 and so on.
If we plucked the note called C, the series of frequencies in the single note created by plucking a string begin with the notes, C, C, G, C, E, and G. There are more overtones, higher than these notes as well.
The frequencies discussed are normally heard as just one small part of a sound, such as one high element of the sound of a plucked string alone, excluding the lower, bassier part of the sound entirely. If we write these out above the root of the note A, these are the notes we get, (including some of the higher, weaker overtones):
Every single string therefore produces a whole “spectrum” of frequencies, and as a frequency may also be termed a “note”, what this means is that every string in fact can produce quite a few different “notes” besides the note that it is actually tuned to. This is what the Spectrum Piano does: it provides the ability to make the upper overtones (or “harmonics”) of the strings sound as desired, without having to make the string also output the lower frequencies at the same time.