Hey, big problem here, i have a Laney RBG 400, combo Bass amp, and only today after playing atleast an hour, i turned it off, and then back on again and it was whirring/buzzing/humming whatever you want to call it.. and this was without a lead plugged into it..

i could plug in and play over it, but when i stopped it was still there, any suggestions to why this might be happening and ways to stop it/prevent it?

if anyone can give some slight help, it would be much appreciated, thanks.

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Electrical interference causes this, but if it didn't do it before then that probably isnt the problem. Sometimes bad tubes can cause this in tube amps. Forgive my idiocy, but do bass amps have tubes?

some bass amps have tubes. But it also could be a loose contact of some sort. Or the speaker cable is a little fucked.

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you might have the amp to close to your stereo or something.... even if the stereo is off it can still cause interference.

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Hey guys, thanks for replying with some answers, just to say, this is the first time this amp has been in this specific room, it didnt happen straight away, it just randomly happened after a while, any more help or ideas to what might be causing this, would be greatly appreciated.

Thanks.

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Is it buzzing from the fans, or the actual amp itself?

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Straight from the amp (speaker) as soon as its turned on..

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it honestly sounds like electrical interference. Look around and see if there is anything nearby that may emit an electical field (TVs, stereos, computers, anything like that)

If not, it may be a cable. Just wiggle them all around and see if anything changes.

It could be a fried resistor, but im quite sure the amp would just stop working in that case. If possible, play the head through a different speaker and a different head through that speaker. Might give you an idea of which one is messed up.

Move it into another room,and then try it.If you unplug the bass,does it still hum?

Try a different outlet, that ones ground may be bad.

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not to point out something seemingly obvious... but, you wouldnt happen to be using a speaker cable as your main instrument cable would you?

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Guys this is a 300 watt, combo, no head no cab, just one amp..

Looks like this, http://www.levytukku.fi/KUVAT/RBG400.jpg

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Bump.

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What have you tried??Have you tried moving it to another room?

Problem solved, it was a input in the back that a lead from inside was going into was loose. cheers.

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Sweet.