CA3080 distortion circuits?

[Steben]

Besides the Lab 5 amps... what do you guys know of the use of OTA as distortion devices?

[Mark Hammer]

The voltage-controlled distortion unit here:  https://hammer.ampage.org/files/Device1-8.PDF

[teemuk]

The new Fender Rumble series of amps (V3) have a very interesting OTA-based distortion scheme: Instead of exploiting non-linear transfer function of an overdriven OTA (like usual OTA distortion circuits) it employs OTAs in voltage controlled amplifiers and introduces non-linearity via that control.

Traynor Dynagain is also an interesting circuit scheme, although it's actually a diode clipping circuit with OTA-based compressor instead of an overdriven OTA.

There is also an OTA based distortion in late 1970's Peavey amps where OTA is exploited for both clipping and expanding dynamics squashed by clipping compression.

[StephenGiles]

The voltage-controlled distortion unit here:  https://hammer.ampage.org/files/Device1-8.PDF

You beat me to it Mark. I hope you are all keeping safe from this virus out there.

[Mark Hammer]

We're good, although with my wife likely working from home much of the time, I won't be testing out any ring modulators or other noisemakers through larger amps in the near future.  We have a reasonably big house, but it isn't THAT big that distracting noises won't carry all through it.  Hope you and Anne are safe.

[ElectricDruid]

Besides the Lab 5 amps... what do you guys know of the use of OTA as distortion devices?

It's reasonably common in VCO circuits of a certain era for producing a "sine" output from a triangle wave input. That soft distortion rounds the points of the triangle. The result is musically sinewavey, even if not good enough for test equipment. Needs a lot of trims for best results though!