1963 Reverberocket distortion

[flant]

I have an old reverberocket with original tubes and speakers. It seems to be distort real easy, quite frankly, it sounds great, but I don't believe it should break up that easy. I have a '66 reverberocket 2 and it's a totally different vibe, much cleaner. The older amp seems to get dirtier and less clean the longer it's on and I play it. Also the power tubes are screaming hot, I know class A amps are known for their heat. My question is, could it be tubes, speaker or caps? I realize this is a lot to ask, but I'm throwing it out there! I love my Ampegs, my list includes a Jet, Reverberocket, Reverberocket 2, Gemini 1, B15nc, B15 n (70's), sp12 (70's). If anyone has opinions, I would really appreciate it!.Thanks

[Amp Kat]

I love the Ampeg series amps and have worked on the old and new reverberockets and have a Lee Jackson that is amazing. If the tubes are worn and red plating they will get pretty hot but red plating tubes will start to hum as they conduct more current than normal. If they are biased hot they may be conducting more current than usual. Volume swells and loss of treble are what you get when tubes go bad or craclking popping and blown fuses. If it has never had a cap job you may considerate as that is a long time for E-caps to last. You can also try maybe putting a 5751 or 12AT7 in the PI slot and that will keep it from breaking up so fast.

[jrfrond]

First of all, that amp is not Class A, it's cathode-biased A/B. Not the same thing, and I don't know why so many people feel they are the same. Secondly, because it IS an old amp with original tubes, caps and speakers, it is more likely for break up sooner. If it sounds good, then leave it alone. Chances are new tubes alone will clean it up, but if your amp has 7591A power tubes, make the investment in NOS. NONE of the new ones sound like the originals, period.

[Amp Kat]

First of all, that amp is not Class A, it's cathode-biased A/B. Not the same thing, and I don't know why so many people feel they are the same. Secondly, because it IS an old amp with original tubes, caps and speakers, it is more likely for break up sooner. If it sounds good, then leave it alone. Chances are new tubes alone will clean it up, but if your amp has 7591A power tubes, make the investment in NOS. NONE of the new ones sound like the originals, period.

Oops forgot that was a Cathode biased amp and agree that it's age could cause it to break-up early as component drift and several other changes have happened over the years.

[flant]

Stupid of me to make that mistake, but thanks for yelling at me and straightening me out! I'll try to find some NOS tubes, I'm in contact with Jess Oliver, you never know what's lurking in his basement! Thanks for the reply!

[flant]

Reverberocket 2

Guys, let me run this by you. I just recently got an RR2 and I notice the bass control doesn't do much from all the way down to all the way up. Could this be a malfunctioning resister on the bass pot? Also the speaker was not original, it appeared to be a no name, so I installed an Eminece Cannabis Rex. What are your thoughts?
PS. I notice the bass control on my Gemini 1 (original Jensen) is amazing, maybe the RR2 should be the same?
Phil A

[mojo2001]

I have gone through a couple early 60s Ampegs. I'd look into a cap job.

If there are any red Tiny Chief or red Astron caps, they are almost guaranteed to be leaky. The green CD and yellow Wima film caps are somewhat more reliable, but all should be checked for leakage. I have even seen a few wax caps in these amps...they are usually leaky as hell.

Ampegs of this era used a real mish-mosh of caps and I can only imagine that they bought big quantities cheap on the surplus market or something.

As you have probably noticed, these amps run HOT which is not good for the electrolytics or coupling caps. Good idea to put a washer between the chassis and cabinet to provide a small crack for airflow...indeed the factory did this on these top mounted amps.