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Hey there. Just wondering if anyone else tried this out or noticed what I noticed.
I was struggling with this 9100 since it always tended to have very present honkey mids or an abrasive treble, depending on how I EQ the preamp.
I switched/biased the power tubes and replaced the front tubes (2x 12ax7 pre-drivers and 2x 12at7 PI) like stated in the owner's manual.
Nevertheless, I always kept having the same issue. Especially when playing with higher output PU's and/or distortion pedals.
Then I looked closely at the actual circuit board and it read "replace valves with ecc81 or 12at7". I did, JJ ecc81 in PI and EHX 12at7 in Pre-Driver.
The honkeyness is greatly reduced, the treble became smoother, the bass tighter and the overall sound clearer and more articulate.
Now I know this is what a 12at7 is supposed to do, but the manual states a different tube than is written on the amp's circuit board.
Anyone else noticed this difference in instructions? Does it have to do with the specifications/capabilities of the original Marshall tubes(white label ecc81 and ecc83) that came with the amp?
I was struggling with this 9100 since it always tended to have very present honkey mids or an abrasive treble, depending on how I EQ the preamp.
I switched/biased the power tubes and replaced the front tubes (2x 12ax7 pre-drivers and 2x 12at7 PI) like stated in the owner's manual.
Nevertheless, I always kept having the same issue. Especially when playing with higher output PU's and/or distortion pedals.
Then I looked closely at the actual circuit board and it read "replace valves with ecc81 or 12at7". I did, JJ ecc81 in PI and EHX 12at7 in Pre-Driver.
The honkeyness is greatly reduced, the treble became smoother, the bass tighter and the overall sound clearer and more articulate.
Now I know this is what a 12at7 is supposed to do, but the manual states a different tube than is written on the amp's circuit board.
Anyone else noticed this difference in instructions? Does it have to do with the specifications/capabilities of the original Marshall tubes(white label ecc81 and ecc83) that came with the amp?