Randall amp problem.

mosman
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Randall amp problem.

Postby mosman » Wed Feb 18, 2009 10:12 pm

I have a Randall G3 150 watt solid state amp which they say is very loud but I wouldn't know as the volume keeps cutting out when I turn the knob over 5. I Googled the subject and found that others are having the same problem but when I took it to get sorted out, the repair guy says he can't replicate the problem. He's got the guys at Randall helping him with info but so far no luck.
Anybody know why this is happening and what to do about it?

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Dennisthe Menace
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Re: Randall amp problem.

Postby Dennisthe Menace » Wed Feb 18, 2009 10:37 pm

mosman wrote:I have a Randall G3 150 watt solid state amp which they say is very loud but I wouldn't know as the volume keeps cutting out when I turn the knob over 5. I Googled the subject and found that others are having the same problem but when I took it to get sorted out, the repair guy says he can't replicate the problem. He's got the guys at Randall helping him with info but so far no luck.
Anybody know why this is happening and what to do about it?

Mosman, VERY INTERESTING, in regards to, I don't think this Group has ever seen a question outside the FORUM, NOT DEALING with a Mosrite Amp...but since you raised the question, let's see if any of the Guitar Gurus know. Unfortunately, I'm from the late 70's, early 80's era, but that's another story for us "Old Farts."..................... ;)
make the Mos' of it, choose the 'rite stuff.
.........Owner of 9 Mosrites...
.....proud owner and documented:
1963 "the Ventures" Model s/n #0038
http://www.thevintagerockproject.com/

mosman
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Re: Randall amp problem.

Postby mosman » Thu Feb 19, 2009 2:36 am

Actually I hoped that someone may have had the same thing with any type of amp and have some suggestion as to what the cause might be—and the solution.

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KRamone27
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Re: Randall amp problem.

Postby KRamone27 » Thu Feb 19, 2009 7:08 am

I would have your amp tech test the volume pot and/or power amp the problem might lie in there.

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Re: Randall amp problem.

Postby Mr. Bill » Thu Feb 19, 2009 10:55 am

Problems like this one are sometimes hard to pinpoint, because they can be electronic or mechanical in nature. But like any other amp problem, they can be sorted out with a little logical investigation.

When you say that it cuts out, do you mean a total loss of signal or a reduction in volume?

Does this happen every time you turn up the volume over 5 or only sometimes?

Is the symptom based upon what you are playing (loud chords, bass strings, solos) or is it random in nature?

Does it happen when you are not playing? (Is the level of noise, hum or hiss affected when the control is turned up with no guitar signal present?)

Have you checked all of the usual suspects like speaker, cords, FX loop jacks, loose parts, etc.?

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Dennisthe Menace
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Re: Randall amp problem.

Postby Dennisthe Menace » Thu Feb 19, 2009 11:01 am

Does that particular model amp have any kind of a compressor built into it or limiter in such that it is
only allowing you to go to a certain volume before the compressor/limiter kicks in??
make the Mos' of it, choose the 'rite stuff.
.........Owner of 9 Mosrites...
.....proud owner and documented:
1963 "the Ventures" Model s/n #0038
http://www.thevintagerockproject.com/

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Re: Randall amp problem.

Postby mosman » Thu Feb 19, 2009 11:54 am

It cuts out for a few seconds and then comes back on but this occurs only when the MV is nudged over 5. Anything before 5 is okay but that's not where I want it. I googled the problem and a bunch of other Randall users replied saying they had the same trouble, but none of them had a solution as far as I know, and it's only with the 150 head it seems.
I've tried different guitars and leads and it happens all the time but it really bugs me that the tech can't get it to happen at all.
And I thought getting a solid state amp would eliminate maintenance worries.
I shoulda stuck with my big, heavy, valve Marshall. At least it always worked.

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Re: Randall amp problem.

Postby KRamone27 » Thu Feb 19, 2009 1:09 pm

Darn solid state amps! :D that's why I went tube. Sure tube amps are heavy and you got to replace the expensive tubes every now and then but they are worth it.

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Re: Randall amp problem.

Postby mosman » Thu Feb 19, 2009 1:18 pm

I'm beginning to see things that myself Kev.
I just hope it gets sorted out before our gig next month.
Bill.

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Re: Randall amp problem.

Postby Killdozer » Sun Aug 01, 2010 10:28 am

Is this a halfstack or a combo? Could be anything from a bad potentiometer to a cold solder joint between the pre and power section. If it's a halfstack have you tried a different cab? This is the one thing I can't stand about SS amps. It can be a pain in the SXXTHOLE to pinpoint the problem, whereas a good tube amp has a more simple layout. Is it under warranty still? Randall have some good customer service, last year on tour when my Mesa lived up to the name "Rectum Frier" (even though it was a Stiletto), Randall over-nighted me a T2 head to help out after only 2 phone calls. They are some good guys, so they should be able to help you. So odd that it's just over 5. Sounds to me like maybe a heat issue or a part that can't handle a certain voltage.


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