I used to jam at a studio and they had Marshall AVT50 heads and cabs. The sound and distortion through the OD chanel was really nice. I just bought a second hand AVT150 expecting it to sound as good as the AVT50. Not overly impressed with it as the distortion in OD1 and OD2 sounds very fuzzy. The guy I bought it from had replaced the preamp tube with the standard marshall tube.
I was just wondering if anyone else had found this and if there are any mods I can do to get rid of the fuaay OD? I cant afford to get an all tube amp, If I can get this one to sound more like the 50 I would be happy.
Any ideas anyone

Cheers