WSG CV questions

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

Hi, I think my cv input not working correctly.
https://soundcloud.com/bmlaster
Here I send 4 octave arp from Minibrute. The range WSG response is very low, high I can improve it? Change 4.7K resistor?

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

Tried 1K instead of 4.7K but it did not help. Pitch become higher, but response the same, not very noticable.

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

OMG, sorry, I messed with pins on 2N5457. It is now working. Was way too high pitched, increased resistor value, and it works.

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

Now I am have strange problem with gate. It did not work first time. I increased gate from 6v to 9.2v and it works but only first seconds when WSG powered on, then it fade out.
https://soundcloud.com/bmlaster/wsg-gate-wtf

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

Can somebody confirm that this Gate schematic is right?

http://www.musicfromouterspace.com/analogsynth_new/WSG2010/modifications/wsg_modifications01.gif

The upper part is working. But bottom not, I breadboarded it like 5 times. When only upper part connected it works, when I connected both nothing happens. When I connected only bottom part nothing happens too, checked resistor, swaped capacitor and diod. Gate voltage around 8V.

brock · Joined: May 26, 2011 Posts: 112 Location: Canada

Can't confirm schematic is right as I've never built the thing, but it looks ok. A reversed diode on the bottom section would stop it from working. Hooking up both paths at once kind of defeats the purpose of the effect as they do opposite things, so will kind of cancel each other out.

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

But I connected it with switch as on the schematic, so only one thing connected in time.

brock · Joined: May 26, 2011 Posts: 112 Location: Canada

ok - I misunderstood, "when I connected both nothing happens", thought you connected the integrating and differentiating sides at the same time.

Seems very strange, the sound sample does not sound right either. The top part of the circuit should be giving you an up-sloping ramp with each gate so you get the "wup-wup" kind of sound and yours seems to come full on, then off. I'd check the part values again, and maybe confirm the fet is wired correctly and in the right place.

Can't understand how connecting the lower part of the circuit can cause the top to stop working unless a value is way off or something is shorted.

Kosmo Mishka · Joined: Apr 18, 2013 Posts: 47 Location: Moscow

brock · Joined: May 26, 2011 Posts: 112 Location: Canada

If the filter isn't working correctly with the R3 pot, adding a fet across it isn't likely to work either. I don't really have any suggestions for the filter right now other than it might be working they way it's designed to, more info in this thread http://electro-music.com/forum/viewtopic.php?highlight=wsg+filter&t=39285.

I don't have any other suggestions right now.