Preamp output problem RM100

[crob1565]

Hi, I started experiencing a strange problem in my RM100. It seems that the output of my preamp section is all over the place....for lack of a better term.

When i first discovered the problem, my deluxe and ultra modules would not work at all, and my xtc only had minimal gain. I removed the two inoperable ones and moved the xtc to another slot assuming perhaps it was the slots. same thing...poor output...

I put them all back in...and suddenly everything was fine and they sounded normal for about 10 minutes. I flipped the amp on standby for a bit...turned it on...and now it seems as if the gain is simply saggy and lacks any real definition. and that is where it has settled. It's been a week or two and the preamp section seems like its just flubby and weak sounding.

However, The power section works fine. I plugged my gsp1101 into the return and it sounds great.

I called Randall Three times over the course of the week, and it seems they don't have any techs available.

All tubes are relatively new with about maybe 100 hours on them. I have three tungsol 12ax7s in the head...and the stock rubys in the modules. they have more play time on them of course.

Has anyone had a problem like this?

 

[Julia]

I had one module, my Deluxe, that when I got it would not play well. Poor signal etc. I'd gotten it used. The one drawback with the modules is that the faceplate and board have to be close to a perfect 90 degrees. This one wasn't. I was about to send it to Pete for repair and then modding, but I noticed it and was able to carefully bend it back to 90 degrees. It now works and no repair was necessary.

Check to see if this is the problem. The modules are pretty fragile. I would make sure I put them back in the box when you don't have them installed. Like I said this is the one drawback of this amp.

If your amp is under warranty you'll need to find an authorized service tech in your region. Even if it's not. You've got to find out if it is the connection inside the amp or the module.

Do you know anyone in your area that has one of these amps? Or a store that carries them? Take the modules there and test them in another amp. If they work fine, then you've got an amp problem and will have to see the tech, If the modules don't work, then I think Jaded Faith or Pete may be able to help you with a repair.

 

[bruce egnater]

It sounds like the input tube could be at fault. This is the one closer to the front near the input jack. Try replacing that with a known good one before taking it in for service.

 

[dorthian]

Hi!!!

i have the same problem with my rm4...
lack of gain, any of my modules sound like crap ....
to play something like acdc or clean stuff it's ok, but for some (extreme) metalish playing, i am forced to use my bbe green screamer with full volume, and gain at noon, and a sonic maximizer + some tweaking on the eq of my gmajor.
i dont understand what happens...

except for tube, is there something i can do to fix this ???