Tubes to brighten up my Mark IV

[SCopeland24]

I have an amazing Mark IV and for the most part I am completely happy with it. The only complaint would be that at times it can be a tad bit dark. So I'd like to know either which of my current tubes is causing this or what tubes I can put in my amp to brighten it up. To be clear I don't want it to be a bright amp, but to just lessen its darkened tone a bit. This is what's currently in it:

V1: 12AX7 Tung-Sol
V2: JAN-GE 12AX7WA
V3: JAN-GE 12AX7WA
V4: JAN-GE 12AX7WA
V5: JAN-GE 12AX7WA
V6: SED Winged C NOS 6L6
V7: SED Winged C NOS 6L6
V8: SED Winged C NOS 6L6
V9: SED Winged C NOS 6L6

 

[SCopeland24]

bump

 

[GJgo]

You should also consider speakers. I've rolled a lot of tubes, and speakers can have just as much if not more difference.

 

[Vigo1999]

I was facing the same issues . . . my IV is really dark also . . . tried different speakers, pre amp tubes and so forth . . . the only thing that really worked was using EL34s . . . from now on my IV will only see EL34s in the outer sockets. :mrgreen: