vintage low power ampeg 15 -20 watts

[rouss]

ampeg makes so many freaking amps its confusing. I love the sounds of the 60s and 70s ampegs . the new ones sound very similar to fenders. The twin 7591 tube powerd ones sound the greatest I think. Could someone tell me what years (a through b) that ampeg switched from 6l6 or 6v6 to 7591. Also what where the names of the small combos ampeg put out powered by 7591. Im looking to buy in the not so near future . I want to research it first Is there a field guide or something on the net like fender has . Any info will be great

[Bruce Clement]

There is a great book, "Ampeg: The Story Behind the Sound" by Gregg Hopkins and Bill Moore. It will answer all your questions. (I don't have a copy of the book, or I would look up the answers for you!)

I have a 1959 Jet, branded as a Giulietti (an accordian company); it has 6V6s. There is a picture of it in that book.

[Javanova]

Have a reverbrocket2 with 7591s which I (mom) purchased in 65 that has a chassis date from 63, so I think you have to look inside.

[erksin]

Low powered 7591-based amps were the '64-'67 Jets, Reverberockets/IIs, and Gemini Is (22w) - the Gem IIs and IVs were 30 watts.

They sound awesome.

[FFTT]

There are quite a few configurations ranging from 18-22 watts in the early models
depending on the tube configurations.

My '64 R12R-M with

RCA 7868's tested 21 watts clean RMS and about 28 watts peak.

If you go with a stock spec low efficiency speaker, the amp will sound
like a very cool 10 watt amp.

If you upgrade to a modern more efficient speaker these amps can get quite loud
and keep up with most live band situations.

The Gemini I has a bigger sound stage and 2 channels that can be jumpered for
2 channel tone blending and more gain. And it has treble boosts on both
treble controls.

[FFTT]

Originally Posted by erksin

Low powered 7591-based amps were the '64-'67 Jets, Reverberockets/IIs, and Gemini Is (22w) - the Gem IIs and IVs were 30 watts.

They sound awesome.

I love both of mine too!

[teleharmonium]

Ampeg was not particularly consistent or uniform, so if you were thinking you could simplify your search to just look for model names and years in order to get a good amp with 7591 power tubes, don't. You'll still have to check to make sure any particular amp you are looking at, indeed uses 7591 or 7868 (same thing except with a wafer base). I've seen surprisingly early amps with 7591 or late amps with 6V6. That said, some models were never made with 6V6.

According to the book, late '63 was basically the time of the switchover. The model numbers for cathode biased 7591/7868 driven amps should be J-12-A (Jet), M-12-A (Mercury), ET-2-B (Echo Twin), R-12-A (Rocket), R-12R-B (Reverberocket), R-12R-T (Reverberocket), Rocket 2, J-12-T (Jet) (compactron preamp tubes), J-12-D (Jet) (solid state rectifier), Reverberocket 2, various EJ-12 models (Echo Jet) and possibly the Gemini IV.

Preamp tubes are another big consideration. I suggest avoiding the later compactron preamp tube models just because it's more trouble to source them, and also avoiding the late 60s models with the thin yellow printed circuit boards, I think they are lesser quality. The darker PCBs are better and hand wired tag boards are my first choice (but I don't have to have them, my B15N has a PCB).

[rouss]

thanks guys

[garretrevels]

just got a '65 Rocket II today!! has the 2 7591's and 2 12AX7's sounds great!! been serviced and has a Weber blue dog speaker.

clean tone for days and the trem is godly!

[FFTT]

These amps have flown under the radar for decades with so much attention going
to similar powered Fenders, but ask the studio players and they love the tones
they are getting from these fine little amps.

One of these days, I'd really like to find an Echo Twin to go with my R12R and my Gemini I, but they are considerably more expensive and harder to find.

One of my friends picked up a cosmetically challenged ET for quite a bargain
and now has a fully functional workhorse amp for well under $1000.00

The ET is a stereo pair of R12R's that can be bridged for all kinds of tonal
possibilities.