Noob question on Operator envelopes

[jonners]

Think I may have just worked this out (after starting up this thread), just wondering if anyone can confirm.

Very simple set up. One OP, no FM and no modulation from any other tabs. Just a quick up/down OP envelope.

I found that if I released the key before the envelope reached point 3, the 'S' point, the sound sustained, slowly fading off.

If I allowed the envelope to complete, it stayed off.

My discovery was that the point 4 makes a difference, even though the envelope would seem to be 'off' by then. It seems that with a point 4 different from point 3, any release of key before the end of the envelope will ramp down from that point to point 4.

That seems strange behaviour (I'm more of a analogue type), easily avoided (by putting point 4 on point 3) but I guess there might be times someone uses it deliberately.

Is there a 'rule' that applies regarding releasing a key part way through an envelope curve?

[LBH]

Think I may have just worked this out (after starting up this thread), just wondering if anyone can confirm.

Very simple set up. One OP, no FM and no modulation from any other tabs. Just a quick up/down OP envelope.

I found that if I released the key before the envelope reached point 3, the 'S' point, the sound sustained, slowly fading off.

If I allowed the envelope to complete, it stayed off.

My discovery was that the point 4 makes a difference, even though the envelope would seem to be 'off' by then. It seems that with a point 4 different from point 3, any release of key before the end of the envelope will ramp down from that point to point 4.

That seems strange behaviour (I'm more of a analogue type), easily avoided (by putting point 4 on point 3) but I guess there might be times someone uses it deliberately.

Is there a 'rule' that applies regarding releasing a key part way through an envelope curve?

Hi,

I have'nt tested, but from your post and image i can say the following.

Point 4 Rate is like setting the Release time in any ADSR envelope. Putting point 4 on top of point 3 (Rate = 99 for point 4) is like setting the Release time in any ADSR to zero. That's no release time.
So i don't understand, if you think that's wrong or different.

In DX7 you then also have the option to set a level for point 4, so the release time can end in giving sound.
You can hear this best, if you go in mono mode. In the example you give in your image, then you should hear no sound, when at point 3, but if you set point 4 to a positive level, then you will hear that level after key release and the release time/ Rate has past.

If the level for both point 3 and 4 is zero, then there will be no level in the release time stage.
But if you release the key, before you reach zero level, then you will hear the sound fade during the release time. This is also just like any ADSR envelope.
If you in a ADSR envelope set S to zero level and have a D time, then if you hold the key through the D phase untill it reach a zero level for the S, then you also hear no sound during the time set for R. But if you release the key before you are through the D phase, then you will hear sound fade from the level at key release during the time set for R.
So again i don't understand, what you think is wrong or different.

in an standard simple ADSR envelope you set the time for A. That's the time it takes to reach max level. D is the time it takes for the level to reach the S level. R is the time it takes to reach zero level from the active level at key release.
To me this is the behavior you describe you exsperience.
The difference for DX7 from a simple ADSR is, that you can set both time and level for all the points in DX7. But the level for the initial start of the envelope curve and the last point is the same.
Also DX7 have extra advabced envelopes with more points you can choose to use instead.

Another case to use a positive level for the Release, is to make drones where you wan't sound all the time.
The point is, you have full control over both time and level for a envelope point in DX7, while you in a simple ADSR only cann set Time for AD and R and only can set level for S.

[jonners]

Thanks @LBH,

I just had a play with the Modular V (accepting that it's still technically digital, but probably operates like the analogue it's based on - I'll try it out on a Sub37 later).

Using the VCA ADSR, yes, you're quite right, setting a 2s A and 2s D, 0% S, and 10s R, I can get the same response.

However, applying a separate EG, with the same settings, to the AM input on the oscillator, with the VCA ADSR set 0s,0s,100%, 0s, the level snaps to zero upon releasing the key.

So that's probably at the root of my confusion.

Like you suggest though - lots of options on the DX-7 modulation, plenty to learn and plenty to play with.

Thanks for taking the time.

[LBH]

Your welcome jonners.

However, applying a separate EG, with the same settings, to the AM input on the oscillator, with the VCA ADSR set 0s,0s,100%, 0s, the level snaps to zero upon releasing the key.

So that's probably at the root of my confusion.

You are talking about Modular V here and not the DX7 V - right?

Modular V have two ADSR envelopes that controls the final output stage. If i understand your example correct, then you have the active envelopes Release times set to Zero (0s).
Assuming the Envelope Trigger is set to Keyboard ON, then you will close the gate at key release, as you have set the release time in the envelopes to zero.

The amps in the mixer section will be modulated, with the modulator you have connected to the AM modulation input, but the output from here shall pass though the final output stage, and that gate you in this example close at key up.

Please keep each topic seperate. DX7 V and Modular V is two different synths.

[jonners]

Ah, yes, of course, the VCA ADSR cuts off the signal from the oscillator, when it has no Release time, I get that.

I've just set up a different trigger on the VCA ADSR so it keeps running at full sustain level after key release, and yes, indeed, the modulating EG Release does ramp down from wherever I let the key go. I'm amazed that I've never witnessed that before - though I have tended not to use long release times.

(BTW I only referenced the Modular V to explore the behaviour of the DX-7 V. If I had posted under Modular V I'd have had to reference DX-7 V to make sense of it, so that would be just as cross referencing. The initial confusion was over DX-7 V behaviour, but I can see now why I've not observed that before.)