1976 DR105 problem.........bad filter caps???

[Buzzardstein76]

i have a 1976 Hiwatt DR105 that i bought a couple of weeks ago. it has been sounding great but the other night halfway through my band's set, it started sounding really fizzy and scratchy and when i would play chords the volume seemed to flutter up and down and the tone sounded terrible. this amp has the original filter cap cans dated the 40th week of 1976. it is not the tubes because i tried a couple of different sets with the same results. does this sound like bad filter caps?

[Buzzardstein76]

i looked at the cap cans again and all of them have a bulge in them. got some replacements on the way

[pet0r]

Don't forget the Bias cap while you're in there, a 100uF 100V electrolytic will do. Not sure if the problem is filtercap related though, but it's a good thing to change them anyway.