My Peavey 6505 head keeps on cutting out. Only recently it cuts the sound out after about 2 minutes, comes back on again and keeps on cutting out, resulting in me standing on stage confused as to what is going on whilst my band give me evil looks!

At practice I use a Marshall 1960B Cab and set the head to 4 ohms as this is the desired ohm setting for my head and cab to work together. Whenever I use a different cab and set it to a different ohm setting - 8 or 16 - the amp will start its temperamental problems.

I have checked all the cables I use, borrowed cables from my guitarist and bass player and the amp seems to be working fine...but only when I connect it to my Marhsall on 4 ohms. I'm using a Dean Deceiver with EMG pickups and have tested the guitar on different amps and my guitar is working fine.

So it looks like I'm going completely wrong in selecting the ohm setting on the head when using a different cab or there are some serious problems going on elsewhere.

Any help with this would be much appreciated,


A short in the output transformer windings could cause this problem. You could test it by playing it on the 8 ohm setting into your 1960 briefly.

I'd bet that's the problem. The good news is that you should be able to use it on the 4 ohm setting. The bad news is that using it on the other settings could destroy the transformer, or it could just go on its own since there's clearly something wrong with it.