Strange Reverb issue.....

[Andrew Lamprecht]

I have this new ampeg that I like a lot. I noticed that the reverb is intermittent. It's strange but the reverb doesn't work when you turn the amp on for a few minutes. After about 5 minutes it will turn on, like it stalls after the amp is warmed up. If you turn the amp up loud, the reverb will work as it should... no issues at all... then if you turn the volume below 2 or so, the reverb itself loses volume. Like it will make little jumps, you can almost hear it turning off, like a little static and it loses a bit of volume after each static "jump." Its hard to capture on audio because it only happens sometimes. It's real spring and tube reverb. Any ideas? PI tube?

 

[GoldenVulture]

Re: Strange Reverb issue.....

? PI tube?

NO- It is driven by a valve usually the last one in the pre-amp chain. The PI comes after that.
Clean the valve pins and the connectors on the reverb tank.

What model Ampeg ?
- http://www.webphix.com/schematic heaven/www.schematicheaven.com/ampeg.html -

 

[ItsaBass]

Re: Strange Reverb issue.....

IME, the controls on those Ampegs almost shut off below 2.

I would first check the tank, to eliminate the possibility of loose springs and/or RCA plugs, and also clean the RCA plugs with tuner cleaner and an eraser. Something you said in your e-mail sounded like the tank itself may have an issue. Then, just for the sake of making sure the amp is up to original specs all the way around, I would replace the tubes with known-good tubes. Also, spray some tuner cleaner into the pots and check the pots' solder joints to the board while you have the panel off. I'd do those simple things first and see what you get.

P.S. FWIW, V1 is described by Ampeg as the ''Preamp Tube,'' while V2 is called the ''Power Amp Phase Splitter Tube.''

 

[ItsaBass]

Re: Strange Reverb issue.....

It's not the take...a tank would either work or not work...

Try the reverb tube first...

Well, it's not the tank, period. I guess that settles it, then.

Where'd you glean that little gem? It isn't true at all, that a reverb tank is either 100 percent or 0 percent, either on or off, black or white. The same model tank on my Jet ''half worked'' before I fixed it; it had lost one of its springs. There could be a spring hanging by a thread cutting in and out, a foreign object that snuck in under the 3/16'' gap that gets knocked into and out of the springs, and there could also be dirty or loose connections on the plugs – any of which could cause poor or intermittent performance. Additionally, I suggested checking the tank because he mentioned to me that tapping it brings the reverb in and out. I never said that the problem is likely to be the tank, but flatly eliminating the possibility, and suggesting to not even give it a look-see (which is easy and free to do) is nonsense.

Finally, this amp has solid state reverb, as I mentioned above when I posted Ampeg's description of the tubes. There is no ''reverb tube'' to check.

Andrew, the Super Jet doesn't have mighty reverb like the 15W Jet II, but it should obviously not be intermittent or require a warmup time.

 

[Andrew Lamprecht]

Re: Strange Reverb issue.....

Haha, I'll try those things, thanks guys... you know what... I like the reverb on this Super Jet more than the Twin I think... it sits back in the mix more but it sounds really nice.

 

[Powdered Toast Man]

Strange Reverb issue.....

Welcome back!

 

[Andrew Lamprecht]

Re: Strange Reverb issue.....

Welcome back!

:wink:

 

[the guy who invented fire]

Re: Strange Reverb issue.....

Well, it's not the tank, period. I guess that settles it, then.

Where'd you glean that little gem? It isn't true at all, that a reverb tank is either 100 percent or 0 percent, either on or off, black or white. The same model tank on my Jet ''half worked'' before I fixed it; it had lost one of its springs. There could be a spring hanging by a thread cutting in and out, a foreign object that snuck in under the 3/16'' gap that gets knocked into and out of the springs, and there could also be dirty or loose connections on the plugs – any of which could cause poor or intermittent performance. Additionally, I suggested checking the tank because he mentioned to me that tapping it brings the reverb in and out. I never said that the problem is likely to be the tank, but flatly eliminating the possibility, and suggesting to not even give it a look-see (which is easy and free to do) is nonsense.

Finally, this amp has solid state reverb, as I mentioned above when I posted Ampeg's description of the tubes. There is no ''reverb tube'' to check.

Andrew, the Super Jet doesn't have mighty reverb like the 15W Jet II, but it should obviously not be intermittent or require a warmup time.

Easy hoss...no need to get excited...

The issue Andrew was describing doesn't sound like a pan to me...I am not saying that a pan can never be intermittent but they are not intermittent in the way he is describing and I had no idea what the amp was when I replied...he said he had an Ampeg with a reverb issue I assumed he had a typical Ampeg with reverb...