MOTM

>>>>
I really like the 8U version that you've got up there now -- looks 
very EMu, partly due to the silver panel. I do have a few questions 
about it. 
<<<<

Thanks! Actually, it's more of a ringer for the Moog 960, feature-
wise.

>>>>
It looks like the horizontal distance between the knobs is less than 
the MOTM standard? If so, it might be worth considering a smaller 
knob size. 
<<<<

Yes, they are 1.5" on center instead of 1.75". There is no need to go 
to smaller knobs - I've tested it in an 8x4 pot matrix and you don't 
feel the difference at all.

>>>>
Does the mode switch allow one to do anything that they couldn't 
accomplish with patch cords? 
<<<<

Not sure if you are talking about the CHAIN switch or the rotary 
stage select mode switches.

If you mean the rotary switches, the answer is: not without adding a 
LOT of jacks to the panel. I don't know how you would do random state 
selection with patch cords, especially on a per-stage basis. Also, 
the rotary switches are more conducive to switching on the fly, 
allowing you to actually 'play' the sequencer in a live performance. 
Last time I checked, people rated the ability to skip a stage very 
highly.

If you mean the CHAIN switch, the same answer applies. If I want to 
make two 8 stage sequencers seamlessly connect to appear to be a 16 
stage sequencer, and support random bidirectional play and random 
stage selection across multiple modules, there has to be a bus that 
the modules use to communicate status and requests. That doesn't 
really lend itself to connection via front panel patchcords.

>>>> 
Why a PIC? Why not just use CMOS stuff? Then you might have to move 
the four bit counter out to a separate module, but that might allow 
for some interesting possibilities for sequencer usage. 
<<<<

The simpler modules could easily be done with discrete logic. I have 
a SuperMoe address generator module designed this way. But once I add 
the rotary switches for all those stage select modes, you have to 
build decision-making into it. The PIC is the easiest way to go, and 
actually ends up being cheaper than the many chips it would replace. 
Not to mention being able to add features in software later.

Let me restate that none of these designs route the actual control 
voltages from the pots through a PIC or ADC - the PIC just controls 
analog multiplexers.

Moe