Audio gain multiplier

I had this fantasy of building a high-gain amp using an OA-105 op-amp module, and an attenuverter, and stuff (you know, like in the real world), but I only succeeded in making an extremely high-frequency ocillator that I could not even hear unless I passed it through a clock divider. :roll_eyes:

Good thing the output was on mute.

Op amps have a very strong low pass filter to keep them stable. Almost like an integrator.

The purpose is not to amplify an audible signal.

Um … With the proper selection of values for R1 and R2 for negative feedback, it totally is, with the gain determined by the relative resistor values. A 741-type op-amp is multi-purpose workhorse device (or was, at least). One of the applications is as a comparator.

But of course that’s in the real world, not VCV Rack plugins.

yes, but if you try to get a lot of gain out of a 741 you won’t get it at full audio bandwidth. See above.

I’m adding this reference Gain–bandwidth product - Wikipedia

yes, that’s it. Mind you, not knowing about this I tried to amplify my guitar by x10,000 in 1977 with a 741 op amp. It sounded good, but mostly because it was so rolled off - I think. Anyway, it sounded great.

The OA-105 is part of my digital suite. It’s purely digital and is an idealised digital comparator. Its not modelled on any real silicon.

For sure. I didn’t really expect it to work, but I thought it would be really cool if it worked at all. It would’ve been what I call a “Dancing Bear”.

“The remarkabe thing about a dancing bear is not how gracefully it dances, but that it dances at all.”

It’s my standard comment for when people try to do something that they know is the wrong way or the hard way, just to see it it could be done.

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