[sdiy] CPLD shield for arduino/AMANI 64/AMANI GT

[Brock Russell]

At 03:52 PM 26/03/2012, Scott Nordlund wrote:

> > I see, you're not making an MK50240 clone exactly, but making a
> > usable top octave generator. That still seems to be quite a trick to
> > get the design done to that few cells. I've been thinking of going in
> > the opposite direction, using a higher frequency clock and a ten bit
> > counter, but the MK50240 type clones I designed use the same divisors
> > as the original.>
>
>By extending the design to use counters, couldn't you extend it 
>further to support other scales (still 12 notes per octave, 
>obviously)? You could regain the freedom that was lost in the 
>transition from 12 individually tunable oscillators to the TOS.
>The irredeemably sick and perverse side of me would love to see 
>someone playing the Wendy Carlos Harmonic and Super Just scales 
>(which consist of 12x12 note scales, set by MIDI foot pedals, so 
>that they can take advantage of just intonation while being both 
>transposable and playable) on a Crumar Compac piano or similar piece 
>of divide down detritus.

Yes, alternate tunings was the main reason I went with four of the 
SLG46400 parts for octave generation. Each part has three 14-bit 
counters and one 8-bit, so it is possible to get an octave using 
three parts, but you have to choose the notes that can be done with 
the 8-bit counters. Just using the 14-bit counters removes that 
limitation. So it's possible to do an MK50240 replacement direct 
plug-in just intonation TOG but it probably isn't practical with 
these parts, but I am thinking about it as I still have the first 
synth I built, a 5 octave version of Don Lancaster's MK50240 based 
design that was in the July 76 issue of Popular Electronics.

On the micro-tonal side, you're not limited to 12 notes if you add 
more devices, so you could easily do micro-tonal scales.