Some time ago I had what I thought was an ingenious idea for a new musical instrument. Most instruments allow you to adjust pitch (within its range) and volume (amplitude). It is often possible to control timbre to a small degree by varying the shape of the embouchure on a wind instrument, for example, but generally you select an instrument and get whatever timbre it produces. Synthesizers allow you to quickly switch from imitating the timbre of one instrument to another, but you are still limited to those pre-defined settings. The exciting feature of my instrument would be giving the musician complete, fine-grained control over the timbre of the sound he or she was producing.
This instrument would consist of essentially a keyboard connected to a 24-track mixing board and a computer. When a key on the keyboard was depressed, the frequency associated with that pitch would be sent to the computer, which would generate a sine wave at that frequency. It would also generate a sine wave at each of the significant overtones of that frequency — an octave above, an octave + a fifth above, 2 octaves above, 2 octaves +a major third above, and so forth. These individual waveforms would then be mixed in proportions specified by the mixing board before being sent to a speaker. The first sixteen or so faders on the mixing board would control the intensity of the first 16 members of the harmonic series. The remaining 8 could serve auxiliary purposes, such as one that boosts the power of all even-numbered harmonics, another for all odd-numbered harmonics, another for overall volume, etc. A person would play this instrument with one hand on the keyboard to control pitch and one hand on the mixing surface to control timbre in real-time.
Because I lack both the electrical engineering skills and free time, this has remained only an unimplemented idea for many years. Today, while scouring the Internet to determine what keyboard instrument makes the percussive sounds of the first solo in “Time Of The Season”, I discovered that the idea described above is essentially that of the veritable Hammond organ, invented 75 years ago, and that the idea of custom-building a particular timbre through combining different members of the harmonic series is as old as the organ itself. The Hammond, and certainly the stops on a traditional pipe organ, are not necessarily designed to be adjusted while playing, but this is a possibility.
The only benefit that my device would have over the Hammond organ would be the ability to find timbres across a more continuous spectrum and greater ease of adjustment while playing. This last benefit may give it the ability to much more realistically mimic the sound of acoustic instruments however, since the timbre of an instrument often changes rapidly between the attack of a note and when it is held over time. Perhaps some day my dream of a note that begins with the full sound of a saxophone, slowly morphs into the pure fundamental of a piano, and accelerates to a breathy flute will come to pass.