simul class 2:ninety clipping?

Im running a Carvin Quad X preamp into the 2:90. At high volumes, the power amp really seems to battle. There's a lot of clipping and mushiness going on.

Im using a 16Ohm V30 4x12 into the 8ohm input of the 2:90.

I had the power transformer replaced to modify the power amp for use with my countries voltage. My amp tech assured me the transformer was good.

any ideas?

i would make sure your power tubes are ok, it sounds to me like theyre old and worn out. you could also rewire your cabs to be 4 ohms.

xcpointx said:

Im running a Carvin Quad X preamp into the 2:90. At high volumes, the power amp really seems to battle. There's a lot of clipping and mushiness going on.

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While I second that you should check your tubes, there is a also good chance that the problem is that you're just running it too hot. It's supposed to get a nice overdrive, but if you push the volume too far it'll clip and mush like that.

Im using a 16Ohm V30 4x12 into the 8ohm input of the 2:90.

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Then you're only getting 45w worth of power out of it. Re-wiring your cab for 4ohm and using the 4ohm output would put you back upto 90w.

90w = more headroom. More headroom = less clipping and mush.

okay, this is great advice! thanks so much guys.

I've been using the retube set offered by Eurotubes, which has supposedly been optimised for the Simul-class....

"Full Retube For The Mesa 290
PRICE: 148.00
DESC: Includes a matched octet of the JJ 6L6GC's in a hotter grade to get that cold factory bias up a little and three matched and balanced ECC83S's for the front end gets you a big fat pure tone. "

It sounds like the 16ohm cab would be the problem, cos I really do like to crank it. And if Im only getting 45W out of it, that would explain why my Marshall SuperBass head has so much more headroom than the Mesa power amp.

Ideally I'm going to try re-wiring the 4x12 cab to a stereo 8ohm cab then. If that doesnt work out, I'll make it a straight 4-ohm cab.

Im using the Carvin legacy cab, which has a PCB jack plate inside!? It has some jumpers and stuff on it which seem to hint that maybe its possible to make this change easily...

Greetings, I would shy away from Euro tube. Some people love JJ's. With my experience from them, the tubes work fine for a few months then frat out.