Now, where's that attenuverter?

[Uncle Krunkus]

I saw a schem for an attenuverter a little while back. Not this one: -
http://www.ori.org/~aaronc/synth/Attenuverter_V1.pdf
It was a different schem, of essentially the same idea, just a little more specific. Does anyone else remember where it was?

[mosc]

Maybe it was in this thread. http://electro-music.com/forum/topic-11431.html

[Uncle Krunkus]

That's the one!
Thanks Mosc

[piedwagtail]

I built two of those Grenader circuits..what he calls a "voltage processor".

Highly recommended!

Robert

[zipzap]

I once tried this type of "antenuverter" and wasn´t happy. I had no pots with center snap, so it felt kind of strange to use.
Another thing is that it´s twice as hard to set the pot to a certain value... nobody else bothered by that?
So i have been using swiches next to the pots to choose for inverting/noninverting operation and keep the full pot rotation for better adjusting. I have some push/pull pots that could be useful, but they only have a simple on-off switch. No good way of using those to choose directuon i guess. Push/pulls with two way swich would be perfect.

[Uncle Krunkus]

You might have a couple of good points there Zipzap.
If you used a simple attenuator made of an op-amp (which I'd need to track down as I have a brain like a seive!) Would the inverter switch swap the inverting input for the non-inverting input in a change over style DPDT setup, or is it simpler than that?

[zipzap]

i wasn´t sure what thos swiches are called, but changeover is what i mean. Well, i was using an dual opamp. Input is fead to both amps, one is inverting, the othe just an buffer. The swich simply chooses which amp is connected to the output.
Many possible ways to do that though.