303 sequencer/res dual pot

[Rob]

pharding at mail.ndirect.co.uk wrote:

>   IIRC the resonance or cutoff? pot is dual ganged.what is the 2nd
> element in the pot doing?
>

Sequencer, sequencer.. You obviously have not heard the Syntecno
TeeBee.. It can crank out the most convincing tb303 patterns using
seq303.. Having heard and fixed a few tb303s in my day, and I am
convinced that with either a Syntecno OR a FutureRetro, there is no need
for a tb303.. The FutureRetro, of course, if you want a *devilfish* sort
of modded tb303 sound with a sequencer built in. Supposedly, the tbs303
cranks fairly well also.

tb303 clones like the syntecno TeeBee have been made without the second
(rightmost) element and it works just fine for the most part. The
rightmost part on the schematics looks like it just regulates the amount
of accent cv being fed into the resonance lines. Fairly simple. Mind
you, you have to figure out a different way to regulate the accent cv in
the proper increments according to where the res pot is. One could
probably scale a simple op amp or transistor circuit to take care of
this by looking at the feedback voltage or current (whichever is more
appropriate) somewhere in the filter circuit and using that to drive the
amount of voltage allowed to come in via the accent. I guess an OTA
would work too..Many different ways.. I know Jared at FutureRetro would
prlly like to do away with the dual-ganged pot since it is a special
order item. It *looks* like Robert Honsbeek @ Syntecno did away with it,
and did a fairly good job of it.

NO one likes the dual-ganged pot... Everybody pick on the dual-ganged
pot!!!! :)

Rob