Every rack wants a Pam's Pro Workout as a master clock.
A Nanorings instead of an original Rings will save you money and 6hp, and work and sound the same.
Calsynth makes a nice one, as does Michigan Synth Works.
Because you're looking at the Doepfer MIDI modules, maybe consider the a-190-5 Polyphonic MIDI controller.
It does what the a-190-2 does x4, and provides many more tricks with the kinds of voice modules you have.
If you stick with the A-190-2 MIDI module, note that the A-140-2 ADSR can be automatically triggered
by the 190-2 if they share the same bus. Saves two wires, overrides with patch cables.
Have it live next to the MIDI module.
Mults. Look at the Frap Tools 333 ProAudio Sum and Distribution module. I use it in almost everything.
6hp, cheap, solid, dead on clean and accurate, and handy for adding CVs (and audio) together,
and then mult-ing them out. I also like the Rides in the Storm QAM Quad multiple.
Very well made at a good price.
You could use more meat and potatoes. Will that A-119 comparitor earn it's 8hp of space?
The A-121-3 multimode filter is 4hp and could help tame and shape some outputs.
Next to that, an A-145-4 quad LFO, because everything could use a little more wobble.
Far more utility in 8hp than the comparitor.
I'll hate myself for this, but a used Maths is going for around $290.
A new Behringer Abacus is $59. Ugly as sin, built to a price, but $231(!) cheaper.
I feel so dirty now.
Modules from 2hp always seem like a great idea until you use them.
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