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Old 8th August 2020
  #19
Quote:
Originally Posted by kingofspain View Post
Unless I'm mistaken, the Blues Juniors reverb circuit is solid state, not digital.

https://elektrotanya.com/PREVIEWS/63..._sch.pdf_1.png

Like a lot of modern amps (the Vox AC30 CC2 included), it's driven by op-amps rather than valves, but it's still driving a good old fashioned spring tank.

Using op-amps is more effficient than valves, which waste a lot of energy generating the currents required to feed a spring tank, plus you loose the need for an extra transformer.
Whether one or the other is tonally superior is in the ear of the beholder - I'm ok with either.

I'll be happy to be corrected on this, but I think from an engineering point of view, op-amp is superior. I'd wager the reason a lot of high end amps still use valves to drive the reverb is less about tonal superiority, more to do with the mains transformer needing extra taps for to feed the op-amps the +/-15V.

More "efficient", possibly, although not enough to make a difference.

CHEAPER, HELL, yeah! one or two 25 cent chips in place of two tubes and a transformer, man, you can save a lot of money in quantity on that. It also sounds like utter crap if you hit it hard. TL0 series chips do not sound good clipped.

And, no, you don't need extra taps. All you need is a couple resistors (5 cents each) for a voltage divider. Dig it - it's REALLY EASY to get a low voltage from a higher one for next to nothing.The other way, no.

Cheap sh!t amps use cc reverb drivers. When you see those it's a sure sign of some pretty nasty cost cutting.

The are solid reasons that good amps use tube reverb. And there are reasons that SS circuits are common for beginner/practice amps.