Coliseum IIb head--honky, harsh sound

[steelguitar]

Hi,
I recently aquired a Coliseum MKIIb head, and I'm getting really nasally high-end out of it and no "sparkle". I have played through Boogies before and was able to dial in a sound I liked, but have so far been unable to do so with this amp. I am thinking it may be the tubes. My solid-state Peavey Nashville 400 doesn't sound this honky so I know something's going on. The presence control only seems to boost the honkiness and not add any, well, presence. I checked the tubes and they all test OK, although it does have a mismatched set of power tubes.

Anyone run across this symptom?
Any recommendations for pre or power tubes to sweeten it up?

Thanks,
Craig

 

[zebpedersen]

Hi,
I recently aquired a Coliseum MKIIb head, and I'm getting really nasally high-end out of it and no "sparkle". I have played through Boogies before and was able to dial in a sound I liked, but have so far been unable to do so with this amp. I am thinking it may be the tubes. My solid-state Peavey Nashville 400 doesn't sound this honky so I know something's going on. The presence control only seems to boost the honkiness and not add any, well, presence. I checked the tubes and they all test OK, although it does have a mismatched set of power tubes.

Anyone run across this symptom?
Any recommendations for pre or power tubes to sweeten it up?

Thanks,
Craig

What cab are you using? Is it class A or Simul (I think they did a Simul IIB @150W)? What tubes are in there?