Matriarch, rising resonance - issue?

[0nemogin]

Hey all. Noticing this lil quirk on my matriarch and wondering if it's meant to be so?

If i turn the resonance up and eliminate the oscillators, so I'm just hearing the resonance... then add some envelope to the filter, having the attack set around 10 o'clock... it's as if the resonance rises to it's peak - at that point, where it sustains, it drops in pitch slightly. As if it rises to 100% but immediately drops to 97% and sustains there.

Seems odd. Anyone else notice this?

[nezzyidy]

We can't know if that is the expected behavior because you didn't tell us all of the filter ADSR settings.
What I can say is that if your filter sustain was set to 97% then what you are experiencing is normal.

[0nemogin]

Sorry no, I of course meant when sustain is at 100% - hence the behaviour being unusual.

The resonance rises to a pitch slightly higher than that of the pitch when sustain is at 100%. Doesn't seem right.

[Synth.builder]

Sorry no, I of course meant when sustain is at 100% - hence the behaviour being unusual.

It is rare for an analogue ADSR to have the levels of the attack peak and 100% sustain to be exactly the same. There is often a small discrepancy between the point at which decay starts and ends. One work around is to set the decay time to its maximum. The envelope will still fall but slowly and with short notes you may not notice it. The other work around is to set decay to very fast so the drop between the attack peak and sustain is very sudden.

Normally when an envelope is controlling a non self-oscillating filter or a VCA, you would not notice this discrepancy. But the ear is very sensitive to pitch changes so if you are modulating a VCO or a self-oscillating filter you'll hear it.

The original Moog modular envelope had a trimmer to reduce the discrepancy but it would never make it completely disappear.

Digitally generated envelopes, and many modern synths will have these, don't have this problem.

Tony

[nezzyidy]

I agee, if you have sustain at max then there’s no reason not to set decay to max. Try that.