[sdiy] Frequency to MIDI Conversion

[Magnus Danielson]

From: harrybissell <harrybissell at prodigy.net>
Subject: Re: [sdiy] Frequency to MIDI Conversion
Date: Tue, 18 Feb 2003 23:49:20 -0500

> I agree with the posts of "it can't be done polyphonically"...
> 
> With a mono signal... you can convert to CV or to Midi.  I'm doing
> this with the PV-1 board (also mentioned) with the CV digitized...and
> fed to a lovely little MIDI board (PIC micro) made by Roman Sowa
> (also of s-diy) which takes a seven bit input and streams MIDI messages.
> 
> I'm quantizing a theremin with it. Theremin is VERY monophonic.
> 
> Both myself and Mike Irwin (co-incidentally...also of s-diy) have used
> a mono synth output to drive the P/V converter.  If you have any CV output
> its better to process that directly. The Juno won't have that...

That nobody proposed the "obvious" solution:

<seriously blond mode>
By magic of feedback you take a spare DX7 (or any other MIDI synt capable of
sine output) and an op-amp. The op-amp takes the mono output of the synth on
it's feedback input (neg) and takes the input signal on its reference input
(pos) and drives the MIDI to the synt and output from the output. Naturally
would it drive the MIDI until the synt phase-locks to the reference signal,
no?
</seriously blond mode>

Seriously, the real lesson is that we need a truckload of conversions.

Cheers,
Magnus