[sdiy] ADSR Plus - 8 parameters?

[Matthew Smith]

I've figured out my digital ADSR generator - microcontroller feeds DAC, 
is controlled by an 8-input SPI ADC connected to a set of 8 pots. (This 
section nicked from my notes on how I might build a replacement for a 
Roland PG-800.)

7 pots accounted for:

* Attack time
* Attack shape (straight line, curving inwards)
* Decay time
* Decay shape (as above)
* Sustain level
* Release time
* Release shape (ditto)

As I have an extra channel going spare, is there another useful 
parameter I could put in there, bearing in mind that I'm not going to be 
doing aftertouch?

Reason for external ADC: I've read in a few places that internal ADCs 
can be a bit, er, rough.

Cheers

M

-- 
Matthew Smith
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