Robotalk 2 and Robotalk RI S&H?

[pappasmurfsharem]

I just emailed xotic about their Robotalk pedals and asked whether or not they have digital processing or are all Analog.

They responded that they are all Analog, so how do they get such good sample and hold results?

I've seen some videos of the maestro S&H clones and other topics about the best transistors to get the best results. But they don't seem to have the solid effect that the Robotalks have.

Anyone know what, if anything, they do differently? Anyone own one?

[Mark Hammer]

Great S&H has always been attainable with analog circuits.  Not sure why you are so surprised.  What exactly is it that you think of when you think "great S&H"?

[pappasmurfsharem]

Great S&H has always been attainable with analog circuits.  Not sure why you are so surprised.  What exactly is it that you think of when you think "great S&H"?

Well of course it attainable, its just that most of the maestro builds ive heard dont always have solid results. I suppose what i would be looking for is something that is "consistently random".

Many of the maestro builds ive heard can at times hit the same frequency multiple times in a row, and of course all the threads ive see where people complain   that they arent getting good results.

I guess my question for you is what should i be looking at?

My favorite sample and hold usage is the intro to "the Camera Eye - Rush" I have the Sonic Projects OP-X for that though

[rousejeremy]

The Robotalk effects are maestro clones. When tuned just right they have a wicked S&H.
Another more interesting version of the S&H effect is the Subdecay Proteus. It sounds great and has a tap tempo.

[pappasmurfsharem]

The Robotalk effects are maestro clones. When tuned just right they have a wicked S&H.
Another more interesting version of the S&H effect is the Subdecay Proteus. It sounds great and has a tap tempo.

Yes that one also sounds solid, so what is the magic sauce?

[rousejeremy]

If I recall correctly it's all about having the right transistor (I think I used a 2N2222 before) and tweaking the trimpot. Have you built one yet?

[pappasmurfsharem]

If I recall correctly it's all about having the right transistor (I think I used a 2N2222 before) and tweaking the trimpot. Have you built one yet?

Not yet. Holding out for the madbean sharkfin pcb to see what it has to offer

[Mark Hammer]

Virtually every S&H I've ever seen the drawing for, that used a single transistor as noise source, noted that one would probably want to try out a variety of transistors to find the one that was noisiest.  This was also true when simply making a noise source.  The circuit may well recommend a particular kind of transistor, but even within any given number, unless we aretaling about a trannie specifically spec'd to be ultra-low noise, some will be noisier than others.

Use a socket, and have several on hand to try out and compare.

It is also the case that the noise source itself may well be filtered, or need to be filtered, to yield a desired response.

[Jaicen_solo]

Is it useful to reverse bias the transistor for a period of time to make it noisier? I've heard that Ge transistors will become hissier if installed backwards in a FF.
Looking at the physics, I'm not sure why that would be, but that's what i've read