Hi, Fred - I just noticed this thread or I would have chimed in sooner. I've been using a Blues Jr with my lap steel for about 5 years (cream board, MIA). It was always good, but not great. I got some incremental tone improvements by:
1. Changing the preamp tubes -- I put a JAN Philips 12AX7 in V1 and new E-H 12AX7s in V2 and V3 (all bought from KCA NOS tubes -- Mike's a great guy). Right away, the sound wa less harsh, more full.
2. Later, I put JJ EL-84s in from Eurotubes. Bob doesn't think the bias is too hot, he says adjusting the bias (per Billm) ruins the tone. Regardless, the warmth and "air" improved greatly.
3. The biggest improvement came recently when I finally did the Billm tonestack, power supply stiffening and simple bias mods. Whoa! More fullness, more air, less honk but still lots of presence. Plus, the tone controls really make a difference now. I still have the stock tranny and speaker, and don't plan to change those for now.
If you want more clean headroom, Bill's tube suggestions are worth looking into, as are others on the Fender Forum (http://www.fenderforum.com/forum.html) -- Read the Blues Jr. Mafia thread for lots of great info.
Best of luck.
Peter
Upgrading a Fender Blues Junior
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