Prophet 5/10 VCA release time behavior

[ACD]

Hi all,

I noticed that when turning the VCA release knob on my Prophet 10, not much is happening to the sound while going from position 0 to 5 (12 o' clock), but a small change from position 5 towards 9 changes the sound drastically, i.e. the release time gets very long quickly. This makes it quite tricky to dial-in the right amount of release.
 
I could not find information on this topic anywhere, so I measured the VCA release time (in seconds) for each VCA release knob position from 0-10 and made a chart 

My question: Is my P10 displaying normal release behavior, or is there something wrong with my unit?

Thanks

[LPF83]

The synth nerd in me couldn't resist, because I think VCF and VCA times (both max and behavior of the curve) are important to sound and in many cases give a synth its signature sound as much as the filter or other factors do.

But to give you some reference points, in my brief test of the VCA release position:
Position 6 - ~3 seconds
Position 7 - ~6 seconds
Position 8 - ~14.5 seconds
Position 9 - ~29 seconds

But yes below 5 is going to be really short and plucky no matter what (that's fairly common in synths, left of 12 oclock being miniscule compared to what happens on the right side of the knob, sort of makes sense from a user experience perspective if you think about it).

I don't know if my numbers are correct but for me they work musically and I never expect analog synths to necessarily do exactly the same thing from one day to the next   So I'm not saying use my values as a baseline but intuitively it makes a bit more sense to me than the numbers you've seen do.

Maybe it's just a calibration thing?  I would try all troubleshooting measures first and then contact Sequential if no change.

[g3o2]

I would also expect the Vintage knob setting to impact the behaviour of VCA release. Set Vintage to 4 for your tests. All in all, your observation is in line with what I observe: only past noon, or even after 1 o’clock, does one start to hear much longer release times.

[Starkstrom]

As far as I can tell the VCA has an exponential scaling which is a fairly common and time proven implementation in synth design. It allows for minuscule editing in the millisecond range to fine tune a short attack transient for example. The fine resolution in this range can make the difference between an attack that sounds like a click versus a “round” but still punchy attack (decay/release).

So I think what you are describing is the correct and intended behavior.

[ACD]

Thanks for the replies!  My takeaway is that my Prophet 10 is behaving as expected then.

Perhaps good if this sort of thing would be explained in the user manual, I think it could help folks to understand their instrument quicker/better.