Hello,
I thought I'd share a set of mods for anyone interested in a bluesy tone from an express.
This is it (just a combination of existing alterations):
1M treble pot, 50pF treble cap, 22k/82k split load on second stage plate, 180k-220k grid leak resistor on third stage. Everything else is A1a specs, with .02 caps in place of .022s (yes, this makes difference by killing lower mid mudrange). This gets you a killer beefed up, overdriven black face type tone.
Best,
Jake
decent mod
Moderators: pompeiisneaks, Colossal
Re: decent mod
Thanks for sharing those and the mods you made on your 12/18 watt. I tried the 22k/82k plate resistor. I thought it increased the clean headroom but didn't notice any change in response of the amp, so I'm confused about "fast/gradual". I will install that mod with a switch in the future to A/B it and may try the Trainflex 1.1 Komet addition that has a couple caps add with the resistors.
I haven't had time recently for much tweaking, but did noticed on Paul Ruby's express the use of a few carbon composition resistors, I think mostly 100k plate resistors and tried those in place of the carbon film. Not sure if it improved the tone, it definitely did not increase the noise or hurt the tone though. The ones I used were all about 104K-108K so I'll order some newer ones and hope they are closer to spec.
I haven't had time recently for much tweaking, but did noticed on Paul Ruby's express the use of a few carbon composition resistors, I think mostly 100k plate resistors and tried those in place of the carbon film. Not sure if it improved the tone, it definitely did not increase the noise or hurt the tone though. The ones I used were all about 104K-108K so I'll order some newer ones and hope they are closer to spec.