Single Voice Processing = Poly-Processing (so far called Hexaphonic Guitars)


this site is dedicated to a about 40 years old effort to improve musical instruments, so far mainly guitars, by treating each string instead of the sum of them. there are many reasons to make this effort - we want to explain them here!

in the first place, its not about high technology or extraordinary sound effects, but the natural and intuitive behavior of the amplified instrument. Any effects that usually are applied even to acoustic instruments work better when they are applied to each string.

for example: Polydistortion is made for those who hate distortion :-)

for a composer its normal to give each of his melody line a different sound, by selecting an instrument for it. for the church organ, hundreds of years ago, they invented to have several manuals for the same purpose. so why should we not be able to play several voices on any modern instrument? But it starts much simpler: even if we use the same sound for all the notes we are playing, we need to process each note separately, below we will explain why.


the two levels of polyprocessing:

- process each voice separately

needed to make effects like touchwah and distortion work correctly (this is available now). for the musician, it only simplifies playing

- give each voice its own sound

lets the musician play several timbres on one instrument simultaneously. needs training by the musician, see Charlie Hunter!
Polysubbass pioneered and of course we can put a different MIDI sound on each string, but there is much more to do.
for example, on the keyboard, the musician could define which fingers produce which sound.

V-Guitar Forum - the best place to discuss all this

Rein Sabolotny(PhD), Taivo Saarts, Vahur Afanasjev: White Paper on Hexaphony

Matthias Grob: Why Polyphonic Instruments?

Troubadour MIDI-guitar Page (abandoned)

the real name for what we do

its hard to start a site without knowing the name of it, or is it harder to find the name of something without a meeting point where we define what we want to name?

everyone is invited to contribute and criticize and we hope to find an agreement and finally give this 40 year old child a decent name which may spread its real value!

the oldest and most spread name is "hexaphonic" hexapickup, hexPU, hexcable, hexamp and such. but hex means 6 and the concept is not even limited to guitar or string, much less to the number 6!

to escape from the limit of 6, some started using Poly which means many. Polydistortion and Polysubbass were created, polypickup, polyamp and polycable also sounds ok, BUT: "polyphonic" is used for hundreds of years by another musical concept. So we would need a version for the whole concept, like Polyprocessing or Polyprocing (unfortunately, Polyproc and Polybass are taken for chemical stuff)

if the name is supposed to be explanatory, it needs to emphasize the SINGLE string or SEPARATE string (well, does it need to be strings? channels?) rather than split or polyphony, because our processing idea does not change the number of notes being heard.

the Greek translation of single unfortunately is heka! so hekapickup and hekaphony works ok, but it seems ridiculously close to the old hexa
very similar with processing which in Greek is ponein so we end up with hekapony for separate processing! Polypony seems ridiculous...

the connector

a central problem of this marvelous technology is the connection between instrument and amplifier

the traditional mono or stereo 1/4" jack is not suitable for instruments anyway since it does not supply the instrument. its dumb to hear a weak battery distort on stage although the instrument is always connected to an amplifier where plenty electricity is available. battery powered circuits are more complicated and rather more noisy. and batteries are a serious environmental problem.
also the 1/4" has its hot contact at the tip so it creates a big noise when its connected which is absolutely unnecessary.
another problem is that the controls on the guitar need to control values in the amplifier where much better filtering can happen and a real volume control (the one in the guitar is a gain control for distortion, or what?)

so we need a better instrument connector anyway which, apart from several audio channels conducts supply and control voltages

solid multi-pin connectors are not cheap. 1985, Roland found a solution that turned into a standard:

the 13pin DIN has the following problems:

  • step on the connector once and its not repairable
  • the ground contact (including supply!) is only on the housing, which is not save, especially since the standard connector tends to oxidate
  • the control lines available are: volume, preset up, preset down. we need more than this
  • the connector is not available in standard electronic parts distributors
  • there is no straight solder or crimp version that can be easily screwed into a guitar