I have no plan for designs beyond the standard M board at this time.
I need to proof and verify that the basic voice card works "as
advertised" so that actually using it to replace broken cards means the
machine still sounds like a CS-50/60/80. Later, perhaps I will indulge
in different filters, more VCOs, etc.
At the moment, my prototype is an old TX-816 rack frame where the
TF-1s (DX voice engines) have all been pulled in favor of boards I made
to test the M board equivalent circuits. Two M board structures per
frame card. I call this thing the CSR-80, because 1) my initials are
CSR and 2) it is a CS-(R)ack frame-80. ;) It is not fully operational
yet, but it does work after a fashion.
The EGs btw are (lowers voice to a mumble) ∗digital∗, using PICs and
calculated rate tables similar to the EG-S chip of a DX voice engine.
They work very well, and if I didn't tell folks now they're calculated
envelopes no one would know without back-tracing the circuit. ;) If it
was an EG that needed to have decay/release rates longer than 10sec
(attack rates are only 0.1sec to 1sec as per Yamaha design) then I would
need more resolution, but this is one area of analog synthesizer voicing
where the microcontroller makes a definite improvement. Making a pure
discrete analog IG00159 EG was taking far too many parts.
Crow
/∗∗/
David Rogoff wrote:
> Hi Scott.
>
> It's good to know you're still working on this! Any plans for
> additional features beyond the original M-Board? I'd really like to see
> a Moog-ladder filter on board. This is one really nice feature of
> Arturia's VST. Also, two, tunable VCOs per board would be great. It
> would let you have much more flexibility than the fixed tunings of the
> Feet selectors and give a massive four VCOs per note!
>
> David
>
>