Thread: What am i missing? (last 8hp)
What kind of music are you making? Do you have other external gear?
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I would probably lean towards a multi-function module like the Disting EX. If you like your rack as-is, the Disting EX would give you access to just about anything else you might need. Sample and Hold, quantizers, noise, wavetable VCO, LFO, tuner, delay, phaser, sample playback... That's probably how I would fill that hole anyway.
Have fun and good luck.