Envelope offset

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berksky
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Joined: 22 May 2006 15:06

Envelope offset

Post by berksky » 01 Jun 2006 12:07

Is there a way to add an offset to an envelope? I would like the starting voltage to be 0 and reach +max at the end of attack. I found it very confusing that the there is modulation at the beginning of the envelope.

karmafx
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Post by karmafx » 01 Jun 2006 12:33

have you looked at the flexible "Envelope" module? where you can add control points by double clicking.

berksky
Posts: 17
Joined: 22 May 2006 15:06

Post by berksky » 01 Jun 2006 18:07

I did (and I love it). However, it has the same problem. The maximum value corresponds to a 0 voltage and 0 in the envelope corresponds to a negative voltage.
So, let's say I want to modulate the filter cutoff frequency. Let's say the cutoff slider is in the midde, 63. Depending on the modulation value, when the envelope is first triggered, cutoff immediately drops, let's say to 0. When the envelope reaches the end of attack, the cutoff is back to 63 (envelope output voltage now at 0). This is fine although unusual. The difficulty arises when the modulation value is not 100%. You have to do the math to figure out what the initial value of the cutoff frequency will be, for example:

initial cutoff value = 63 + (-max env output * modulation)

I would prefer

initial cutoff value = whatever the slider is set to
cutoff at end of attack = slider value + max env output * modulation

Is there a way of doing this? I think what I need is a way of adding a constant voltage to the envelope generator that is equal to it's max voltage so that it starts at zero and peaks at +max env value. I just can't figure out how.

Any synth I have ever used has envelopes that start at 0 and either goes up or down from there. Of course, on a modular synth, you can modify this by using an adder.

Am I making sense?

karmafx
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Post by karmafx » 01 Jun 2006 18:55

I may have misunderstood what you say, but it sounds like you can achieve this easily with a flexible envelope.

Kick the envelope into bipolar mode and let the envelope start from 0 (center of display). Have it rise to some value and then all the way down to -1. Set cutoff to some value and modulation to 1 (center).

This should give you:
initial cutoff value = whatever the cutoff was set to
cutoff at end of attack = cutoff value + max env output * modulation

would that work... ?

berksky
Posts: 17
Joined: 22 May 2006 15:06

Post by berksky » 01 Jun 2006 20:04

It sounds like it should. Cool. I will try it as soon as I go home. Would it be possible to add a switch to ADSR to do the same thing? Envelope is great but it is sometimes an overkill. It sound like this is 3rd envelope option:

1. default (negative), range -[max, 0]
2. bipolar, range [-max, max]
3. positive, range [0, max]

-Berk

karmafx
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Post by karmafx » 01 Jun 2006 20:50

I think you should be able to option 3 in ADSR by inverting and dragging the volume slider to 0. This makes the signal wrap around to the [0;+max] range, while still looking like a normal envelope (due to the invert).

berksky
Posts: 17
Joined: 22 May 2006 15:06

Post by berksky » 01 Jun 2006 21:02

Will try that too :-) Thanks. And I apologize to all for keeping the only developer from working on the next release.

berksky
Posts: 17
Joined: 22 May 2006 15:06

Post by berksky » 01 Jun 2006 23:29

Awesome. Both work. So now, I have another question :D
The Envelope module does not seem to have a release stage. When I release a key, it completes the whole envelope no matter where it is. Is this intentional? Or maybe it is there but I don't know how to activate it?
I am just starting to use it and it really rocks.

karmafx
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Post by karmafx » 02 Jun 2006 18:59

To jump to the release position seems wrong as it most likely creates a glitch in the output, so yes it finishes what it is doing (in sustain) and continues into release. Is there another way you would prefer it to function ?

berksky
Posts: 17
Joined: 22 May 2006 15:06

Post by berksky » 04 Jun 2006 13:12

Similar to ADSR? Start releasing from the voltage when the key is released? The voltage doesn't have to jump, just start releasing. The way ADSR does it.

berksky
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Joined: 22 May 2006 15:06

Post by berksky » 04 Jun 2006 13:16

The new release is totally cool by the way :-)

robenestobenz
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Joined: 01 Oct 2005 03:08

Post by robenestobenz » 04 Jun 2006 16:19

berksky wrote:Similar to ADSR? Start releasing from the voltage when the key is released? The voltage doesn't have to jump, just start releasing. The way ADSR does it.
Seems like the best solution to me.

karmafx
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Post by karmafx » 04 Jun 2006 19:42

ok...I'll look into it. Thanks !

Glad you like the new release btw ! :)

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