On 1/31/00, The Old Crow <
oldcrow@...> wrote:
>
> What would people think about an 8-stage EG with VC inputs based on a
>fast microcontroller with some 12/16-bit A/Ds, DACs and mux-s/h. Good old
>PIC or Z8 single chip uP would be fairly simple to set up for ~2ms to 20s
>times without audible stepping given sufficient DAC resolution.
>
> To make LEDheads happy, could have transition-state LED indicators for
>when one stage transited to the next.
It would HAVE to have a gate-detected indicator LED at least, and you
could flash that when it changes stages. My latest (2 year old) idea
for a multi-stage EG consists of a series of 8 stages, with each stage
having 3 parameters: ramp-to voltage, ramp rate and sustain switch.
The ramp-to voltage and ramp rate allow various timings and slopes, and
the sustain switch causes the processor to stick on that stage until
it detects a gate off. I planned on using a PIC chip as a controller
for JH's VC EG idea using 2 NPN and 2 PNP transistors. This seemed to
be easier than using a DAC. I would use a window comparator to determine
when to change stages. This is quite similar to the Roland MKS-50 EG,
only extended beyond ADSR.
I would LOVE for something like this to become a MOTM module!
I would envision a multi-stage EG as having 15 or more knobs and
6 sustain switches; or 2 rotary encoders, 3 push-buttons and
an LCD panel [add 8 jacks for voltage controll]. The buttons would
be next/prev stage and sustain toggle. You could also use the
next/prev buttons as next/prev feature if you added several parameters
to each stage.
The 16 knob variant starts sounding like a sequencer doesn't it?
Either way, a PIC controller tied to an analog VC-EG stage would
allow for voltage control without worrying about stepping.
Either way, I'm not against your idea, and in fact would like to
have one. You could add a gate delay, and a punch option to a
digital EG quite easily. And for what it's worth, I vote for
using a PIC since I already have a PIC programmer.
Regards,
Roy Tate
Roy Tate
roytate@...