manymanyhaha wrote:The side/difference signal wouldn't be affected by the Whammy, right? I read OP's question like they were trying process two signals with a mono effect but keep them separate. Maybe I'm misunderstanding? Sounds like an amazing circuit idea, trying to think how it my be useful to me!
One of those two signals could be fed to the whammy and then re-united in an attempt to use a mono effect on a "stereo" signal without killing the separation.
I'll try to help understanding (forgive me if I wind up muddying the waters instead)
Instrument has output A and output B.
These two channels are fed into a circuit, which output these channels:
1) A+B (mono sum),
2) A÷B (a monophonic signal that contains neither A or B, but only the differences between them, division is probably not 100% accurate an analog),
3) A-B (which technically is just A+B with either A or B polarity inverted to sort of suck out the common ground without being as heavy handed as "channel 2")
4&5) which is a pair of outputs sweepable between A+B and B+A (two mono channels) to A-B to B-A (two channels pushed to extreme with no "center image") - the center position on the knob amounting to normal A and B unadulterated stereo
6) technically I also included an everything sum channel, but in actuality it's just a noisy mess (included here because the eagle eyes among you can see the obvious additional output on the pictured build.
In thinking about it, channel 2 & 3 are functionally similar, but I believe the result is different. One is set up like a differential instrumentation amplifier, the other is just brute forcing voltage drops across a couple summing resistors before being fed into a bog standard opamp stage. They both null "common" waveforms, so it is entirely possible I overthought this project. Caffeine in the morning is a wonderful thing.
Anyway.
We have two sources.
Let's grab the mono sum 1 and feed the whammy. Whammy does what whammy does and then maybe splits and resistance sums with output 4 & 5 set to widen a bit? that might work, and will certainly result in two different outputs. Though it's possible we're bumping into the realm of cancellation which can effectively shit on bass frequencies.
Maybe feed the sum to whammy as before, and then take the difference channel and resistance mix that to one of the outputs?
Or go true mid/side and sum whammy and difference on one side, and invert difference before summing to whammy on the other? (this one requires an additional inverting stage to accomplish)
Or send the difference to the whammy and choose your return path.
Or set the difference up on its own loop, etc..
All my circuit is doing is some analog "math" between two signals. It does
not do multiply, which is ring mod or VCA territory. It really is just a utility stage and not some whiz bang thing on its own (or I would be closer to developing it as a product). It serves as a strange splitter in my world, allowing for some mixing goofiness. It does benefit from truly different signals, as I have been let down while listening to the "stereo output" of say, and old synth, which just makes stereo from a chorus (and as cool as chorus can be, listening to that effect in isolation was not the ripping experience I had hoped for, hahaha). Anyway, if it can be of assistance, it exists as a raw PCB and need only be stuffed with jellybean parts (there is one bodge in which gain setting feedback resistors need small compensating bypass caps to eliminate supersonic oscillation - this will be included when I'm officially selling these as DIY stuff - so knowing guinea pigs only for the moment)