Other Amps

Calling Powdog (or other amp techin’ guru) for Ampeg mod

1

I've finally made myself sick with guitar excess, and am starting to cull some functional duplicates.

In the process, in a roundabout way I only mention because column inches are free on the internet, I've rediscovered the Reverberocket 2 as quite possibly the Best Amp In the Known Universe. For the moment. To me. No doubt there are others.

But you get what I'm saying. It's a marvel. One of its marvels is its exquisite clean tone, which is simultaneously distinctive, flattering to every guitar I plug in, and transparent.

It's this transparency which is helping me evaluate functionally similar guitars - their qualities of tone, response, and note envelope are laid bare in back-to-back comparisons through the Ampeg, at the same settings. Makes it easy to decide which ones to keep, and which go.

But that's not what we're here to talk about. That's just to say I'm smitten once again by this jewel of an amp.

The last time I brought it up it was to mention that its only fault is maybe not enough low end; I think someone suggested a speaker swap. I didn't do that, but I have hooked up a great parametric eq, and a little boost of shelving lows is all it takes to warm the Ampeg up (on guitars where that's needed). That lets me keep all the tonal wonder of the original speaker.

For impatient readers, here's the real question. Now I have another nit-pickin' nit to pick. The tremolo doesn't get slow enough to suit me. Can that be "fixed?” I mean, are we talking about a couple component changes, or more major surgery?

For reference, this is a Model GS-12R.

Thanks, fellers.

2

Probably cap changes (different vlues) in the tremelo circuit. I'll have a look at the schematic, Powdog is probably much better versed. Or you can go over to the hoffmans amps forum and ask someone there.

3

Increasing the value of C21, C22 and C23 from 0.047 uF to 0.068 uF should do it.

4

You can also adjust the intensity/depth of the oscillation if you’re not happy with that.

5

My amp tech did it to one of my Fenders; he said it was easy. That is a very cool amp and that effect where you turn the tremolo all the way up until it clicks and the space age effect kicks in is way cool. I had one of those but let it go, only because I had too many amps and I'm not a collector. Those old Ampegs, with their upper mids are great foils to the Fender scooped sound.

I still have the earlier version; a 1962 Reverberocket R-12-R. A couple of weeks ago I was playing a jazz gig at an outdoor festival with just the Ampeg and the old single pickup 6124 and the sound guy kept coming up to the stage and looking at the gear. He said that he could'nt believe that was all there was as it sounded so good out front. I'm with you on those being great amps.

6

Thanks, GG. That’s pretty specific info. Maybe I’ll give it a whack.

7

Tim, You could leave the original components in place and piggyback some .022 uf capacitors on top of the existing ones to slow down the tremolo. I'd try one at a time, until you achieve the desired result of slowness.

8

Tim, You could leave the original components in place and piggyback some .022 uf capacitors on top of the existing ones to slow down the tremolo. I'd try one at a time, until you achieve the desired result of slowness.

– JBGretschGuy

That a good way to do it: no de-soldering until you're sure of what to do.

9

Good suggestion. If they work, I’d just leave them. Make it easier to reverse the mod later without leaving evidence.

10

The .047’s are easy to get to, and Jupiter’s would blend right in.


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