Overriding MIDI and a (possibly screwy) Idea

[John Speth]

At 04:31 AM 2/5/97 GMT, you wrote:
>I had this brain pain that resulted in this:
>
>Perhaps this has already been done, but...
>One could build a CV record / playback device using a stereo tape deck
>and some PLLs.  If FSK were employed, one could record several CVs on
>one stereo channel, I'd guess that 4 or more should be possible.  Each
>CV would be recorded by feeding the CV at performance time into a VCO,
>(perhaps a 4046 used as a VCO).  Each CV VCO range would occupy it's
>own band within the audio spectrum.  The outputs of the VCOs are then
>mixed and recorded.  Stereo doubles the number of channels.  On
>playback, the CVs are recovered by PLLs, possibly the same 4046 ICs
>that provided the VCOs to record the CVs.  It might also be possible
>to use FSK to record gates as well.  The CVs and gates would then be
>plugged into the synths that were used to record.

What you suggest is an "analog event recorder".  I'll bet you can find old
lab equipment that will do this just fine.  I'll also bet that you can find
the modern software equivalent that uses a multi-channel ADC/DAC card and
runs under Windows.  That's the way I would go (my personal preference).
You could (if you're so inclined) write a program that would sample the ADC
periodically but often enough and log changed analog values with
timestamps.  Then you could play back the log with analog values metered
out accrding to the timestamps.  The software solution gives you a nice
front panel with the possibility of adding MIDI as a software exercise.

John Speth (johns at oei.com)
Object Engineering, Inc.
Vancouver, WA