VCA modulation

[Horse]

I'm finding my way around my rev2 having only had it a couple of weeks. Currently on 1.1.4.5

One thing which has puzzled me is that if I initiate a blank patch and set an LFO destination as VCA, then I get sound generated before I even press any keys. No usb or midi connections. I don't understand what is triggering this - is it something I'm not understanding, or possibly a bug?

Unrelated - I've been trying to use envelope 3 to recreate the effect of turning the fx1 parameter knob with the FX set to a delay. I can link up env3 but never achieve the same cool sound I can get by just turning the knob - any thoughts appreciated on this too thanks

Cheers

[aeonn]

One thing which has puzzled me is that if I initiate a blank patch and set an LFO destination as VCA, then I get sound generated before I even press any keys. No usb or midi connections. I don't understand what is triggering this - is it something I'm not understanding, or possibly a bug?

Be reassured, it’s totally normal. Think of the oscillators as components that are constantly sending a signal. They are always making sound. To tame that, the VCA behaves like a gate that opens and shuts the door for the signal, but the gate takes the form of the VCA enveloppe (so you have control over the DADSR) and it’s triggered every time you hit a key. This way, the sound come out only when you play, and with the enveloppe shape that you want.

Now, when you send an LFO to modulate the VCA destination, you bypass the VCA enveloppe so every time the LFO reaches its maximum value, it will fully open the VCA amount, so you will hear the oscillators periodically according to the LFO shape and rate. This kind of modulation is often used to create a tremolo effect, when you set a negative amount value in the destination slot.

Hope that helps

[Horse]

One thing which has puzzled me is that if I initiate a blank patch and set an LFO destination as VCA, then I get sound generated before I even press any keys. No usb or midi connections. I don't understand what is triggering this - is it something I'm not understanding, or possibly a bug?

Be reassured, it’s totally normal. Think of the oscillators as components that are constantly sending a signal. They are always making sound. To tame that, the VCA behaves like a gate that opens and shuts the door for the signal, but the gate takes the form of the VCA enveloppe (so you have control over the DADSR) and it’s triggered every time you hit a key. This way, the sound come out only when you play, and with the enveloppe shape that you want.

Now, when you send an LFO to modulate the VCA destination, you bypass the VCA enveloppe so every time the LFO reaches its maximum value, it will fully open the VCA amount, so you will hear the oscillators periodically according to the LFO shape and rate. This kind of modulation is often used to create a tremolo effect, when you set a negative amount value in the destination slot.

Hope that helps

That's a very helpful explanation thank you. I had been aiming for a tremolo effect, and have managed it by using the mod matrix to assign lfo1 to VCA with a negative value. So presumably the negative value keeps the gate closed until the envelope pushes it into positive territory following a key press, and at that point I can hear the lfo working?

So the dcos are always singing away behind the scenes based on an initial default value or the last pitch they were assigned?

[aeonn]

That's a very helpful explanation thank you. I had been aiming for a tremolo effect, and have managed it by using the mod matrix to assign lfo1 to VCA with a negative value. So presumably the negative value keeps the gate closed until the envelope pushes it into positive territory following a key press, and at that point I can hear the lfo working?

  Yes that’s it.

So the dcos are always singing away behind the scenes based on an initial default value or the last pitch they were assigned?

Exactly. It can lead to interesting effects if you play with it

[panic]

the other way to achieve tremolo sounds is by not using VCA level as your destination, but simply using the amp-env amount instead (no need to use negative values for your LFO then, but make sure your env-amount is not set too high, otherwise you don't hear a lot of tremolo, since all modulation sources add up).

On your other question: I only have a mopho-tetra, so no effects there, but normally, sweeping the effects manually or with an envelope should produce similar results. Could you describe your problem a bit more detailed?

[Horse]

That's a very helpful explanation thank you. I had been aiming for a tremolo effect, and have managed it by using the mod matrix to assign lfo1 to VCA with a negative value. So presumably the negative value keeps the gate closed until the envelope pushes it into positive territory following a key press, and at that point I can hear the lfo working?

  Yes that’s it.

So the dcos are always singing away behind the scenes based on an initial default value or the last pitch they were assigned?

Exactly. It can lead to interesting effects if you play with it

Thanks again - funnily enough I found some 'interesting effects' whilst trying to understand this. Realise now I also hadnt grasped the different +/-  statuses of the different LFO shapes, which was also adding to my confusion.

[Horse]

the other way to achieve tremolo sounds is by not using VCA level as your destination, but simply using the amp-env amount instead (no need to use negative values for your LFO then, but make sure your env-amount is not set too high, otherwise you don't hear a lot of tremolo, since all modulation sources add up).

On your other question: I only have a mopho-tetra, so no effects there, but normally, sweeping the effects manually or with an envelope should produce similar results. Could you describe your problem a bit more detailed?

.

That's handy thanks. Hard to explain what I mean re the delay - I'll try to record some samples