Shades as an osc mixer? Or am I an idiot? Or both

Ok, I’m confused. If I mix audio, say drums from Peaks, through Shades, everything works how I expect it to. If I mix oscillators through the Doepfer A-138M, the behaviour is as per an audio mixer, i.e. the waves don’t affect one another. However, if I mix oscillators through Shades, I get some kind of phase cancellation or something going on. Sounds great but I don’t know why it’s happening.

Example:

Sine into Ch 1 with no output.
Triangle from the same osc into Ch 2, output to mixer.

With the Ch 2 knob fully CCW, the sine sounds like it’s being waveshaped, or folded or something. I think I’d expect this with nothing going into Ch 2 because of the 5/10V thing. I think.

If I have sines going into Ch 1 and 2, and output from 2, I get phase cancellation.

I think this is all to do with why Blinds can be used as a ring mod, but regardless any useful insights would be appreciated. I’ve tried unipolar and biopolar by the way. Can Shades be used as an oscillator mixer if I don’t want them affecting each other?

Frames also acts how I would expect by the way, i.e. no change to the original sounds, just a mix of them.

Yes, Shades can be used as an osc mixer, no issue at all!

A .wav audio recording, or oscilloscope traces would allow me to understand your problem!

Maybe it’s just a matter of clipping (in Shades if your oscillators are particularly hot, or later in the signal chain?)

Maybe a channel of your module is defective?

Are the sine waves at the same frequency and phase?

No, Blinds can work as a Ring mod because it’s a VCA which inverts the phase of the input signal when the CV goes negative (as opposed to a “regular” VCA which would mute the signal in that case). Shades is not voltage-controlled, it’s a completely different design!

Thanks.

Pic below, this is the output of channel 2 with ch 2’s knob fully CCW. If this is clipping I get the same issue running the signal through an attenuator before Shades. The sines were not the same frequency and/or phase, however the wave below is from the sine (Shades ch 1) and triangle (Shades ch 2) outputs of the same osc (WMD Spectrum).

This is a sine wave with a DC offset added to it, to the point that it clips.

It looks like the module doesn’t receive the triangle signal at all, so instead the gain control adds a positive offset to the signal. Maybe channel 2’s input is defective?

What happens if you send the triangle to channel 1 and the sine to channel 2? Do you get instead a clipped triangle? And if you now patch a cable into output 1, what do you get on output 2?

Hi.

First scenario I get a clipped triangle. With a dummy cable in output 1 I get a clipped sine again.

Use the contact form on the Mutable Instruments website, I’ll send you the instruction to send the module for repair.

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Ok, thanks a lot.