EG ! explanations, tricks and tips

[forficule]

Hello there, I get confused with the EG, and some knob with EG, I'm sure I'm not alone...
Can we post here some explanations, some tricks and tips and some example ?
First of all, let's make it clear, how does EG INT work ? How does it affect ADSR ? Then how does EG/GATE work with ADSR ?
Thanks

[ugocapeto]

EG INT stands for Envelope Generator Intensity, it modulates the pitch using the ADSR as the envelope.

http://korgds-10.blogspot.com/2009/02/e ... or-eg.html

http://korgds-10.blogspot.com/2009/02/pitch.html

if you want to learn more about all this stuff, it may not be a bad idea to invest into a sound synthesis book. it seems complicated but it's really not rocket science.

hope this helps.

[ugocapeto]

back in the day, i wrote a bunch of articles about what did what on the Korg DS-10:

http://korgds-10.blogspot.com/search/la ... 0%20School

i had to read a couple of books because i had/have about 0 clue about synthesis.

[forficule]

Such a usefull blog, thanks !

[forficule]

Ok let's start with the eg int under octave and porta...
If you turn it you get your adsr working as a pitch enveloppe ? But do the adsr still work ?

With the vca, if you choose the gate switch, does it mean the adsr is out ?

Then what about eg-int all the way to the right, vca with gate, does adsr still work for the pitch env ?

Sure there's some tricks around...

[ugocapeto]

there's another question that could be asked:
if you select GATE as the VCA EG, then what EG is used in the patch bay when you connect EG to VCA IN? The gate or the ADSR? I'd think it's always the ADSR but not sure.

I don't have the ds with me so it's just my 2 cents...

Q: If you turn it you get your adsr working as a pitch enveloppe ? But do the adsr still work ?
A: Not sure what you mean, the adsr is certainly on for the filter and the amplifier. I mean ADSR is just an envelope that you're free to use for modulating something else (volume, pitch, filter), in other words, it's a shaping tool for something else. by itself, it does 0.

Q: With the vca, if you choose the gate switch, does it mean the adsr is out ?
A: The adsr is on for the filter but is it on in the patch bay for when you connect EG to VCA IN (see my own question above)? I think it is.

Q: Then what about eg-int all the way to the right, vca with gate, does adsr still work for the pitch env ?
A: I think so. I think the gate as a modulation envelope can only be used for the amplifier.

The only way to tell for sure is to turn on the thing and see what happens. On top of that, there could be bugs that give results that were not intended. I rarely use the GATE as an envelope for the amplifier.

Note that usually synths of that type have 2 ADSR: one for the amplifier and one for the filter.

[forficule]

I've found something intersting... Let's start with the default synth 1.
PITCH all the way to the right, EG INT all the way to the left
VCO : vco1 and 2 square, sync off, vco2 pitch 3 o'clock
VCA : lvl at max, drive 7 o'clock, and GATE
VCF : cutoff 11 o'clock, peak 3 o'clock, EG INT all the way to the right
EG (adsr) : A 7 o'clock, D 2 o'clock, S all the way to the right, R 2 o'clock
Then the PATCH : vco2 in vco1 pitch 11 o'clock, and EG in VCA 4 o'clock
You'll get a big porta ! I've played it with c5c5c5_c4_c6_c5c5c5_c4_c6_ and it sounds pretty good...
I think that the EG in VCA in the patch max the EG INT when the ADSR env becomes a pitch env...

[DS-10 Dominator]

Interesting topic ! Keep the envelope generating!

[fluid]

Okay, so the Envelope Generator isn't that complicated. It's just a standard ADSR envelope. You can think of an envelope as a value that you can modulate. What it primarily modulates is volume (unless you switch the VCA EG to Gate, in which case the VCA bypasses the EG and volume remains constant*).

What is the ADSR envelope? Attack Decay Sustain Release. Attack determines how long it takes the note to reach its peak volume. Decay determines how long the note takes to reach steady volume while it is still being held. Sustain determines how loud that volume is. Release determines how long it takes for the note to stop playing once released. Since the EG can modulate more than just volume, you can substitute whatever you're modulating into those sentences (eg filter cutoff).

On the left side of the synth, you've got the pitch section. Those knobs modulate pitch. The EG Int knob uses the ADSR envelope generated by the EG to modulate pitch to the degree that you turn the knob. If you turn the knob to the right, you'll increase the degree by which the envelope modulates pitch. If you turn it to the left, the envelope flips over and you get the opposite effect.

Same goes for the filter and for Patch mode. You're just modulating whatever you're plugging it into with the filter that you've created with the EG knobs.

*The purpose of the Gate position is to allow the use of the EG to modulate other things without modulating the VCA.