Solid State Guitar Amp Forum | DIY Guitar Amplifiers

hey guys,

this is my first post and my first serious repair on a SS amp. I have a Carvin B1500 that has sat on the bench for some time now.

The prognosis?

I turn it on - lamp ocmes on but the 5Watt resistor across the power input heats up so much it actually glows red and you get that "burning" smell.

I've poked around with my multimeter but to no avail - however - i've just been checking continuity.

Adivce?   Would changing the resistor be the fix - or is it heating up because of another compromised component - like a voltage regulator?

Thanks.

Dear Brooklynhero. I think that first of all, you should try to get the schematic. I´ve got it somewhere, but to save time, try to get it yourself. The Carvin guys are great and helpful, you can download it from their site, I think that section is called something like "legacy", "museum", or something like that. Not very sure now, but it either used a lot of MOS devices or "heavy" bipolars such as MJL21194 or similar. Anyway, I remember it was a big, professional head. I´ll check it when I get to my workshop. I think that that 5W resistor (value?) is not "across" your "power input" but very probably is an output transistor emitter resistor, indicating very probably a shorted output device. See you soon.
JM.

This is the 1500 watt  rack mount power amp right?

NO - it the B1500 rack mount BASS amp. pretty new.

I tried shipping the amp once and it must have been dropped considerably. Yet I see no physical damamge to the innards - the tranny moved a bit.

I'll see if I can get my hands on the Schem.

I turn it on - lamp ocmes on but the 5Watt resistor across the power input heats up so much it actually glows red and you get that "burning" smell.

what is the resistor(1K ohm, 2K ohm .... etc )

                                  Rock On