Clipping questions: most pleasant decay

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The G
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Post by The G »

Hi guys,

I wonder what do you like best for an mid-gain/high-gain solid-state clipping stage.
I tested or read about:
1. antiparallel small signal diodes or equivalents (LED, BJT, FET) in the negative feedbak loop
2. antiparallel small signal diodes or equivalents (LED, BJT, FET) to ground
3. gain stages with transistors (BJT, FET) or operational amplifiers
4. CMOS inverters (CD4069,CD4049,CD4007)
5. small power audio amplifier (JRC386 or LM386)
6. combinations of the above
Maybe there are more, feel free to correct and complete my list.

I've tried most of the list (I have yet to experiment with LM386). My personal preferences are CMOS inverters and opamps. But I don't like the sputtery decay of the opamps at low/mid gain and the CMOS inverters seem noisy to me.

So: which one decays most gracefully for you? Or, there a certain way of setting the circuit to obtain a smooth decay?
What can be done to make the opamp clipping decay a smooth one?

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The G
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Post by The G »

OK, I'll answer myself: right now I like FETs most. They have ear-friendly distortion with nice decay over the whole gain spectrum and they can be made into low-noise circuits. I still don't like the distortion of mu-amps, SRPPs, cascodes or whatever. I heard nice samples, but when I try them myself they dissapoint me after a few knob turns.
I also like the CMOS inverter distortion, but CMOS inverters have way too much noise.
I like the high-gain distortion of opamps, but the decay is just horrible. And at low gain you'll notice nothing else.
The rest of the pack - diodes or whatever in the NFB or to ground: meh... Their problems are not that visible as with the CMOS inverters or opamps (if you look/listen closer, you'll notice them), but their qualities are also behind enough.

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