Excellent explanation, so good it should be a stickie! Thank you.
EDIT P.S. OK, just did some end-of-chain, post-OBEL, before preamp experiments with my Reverend Drivetrain. Experiment failed (or should I say, produced negative results - ruling something out empirically is never truly a failure). Sounded awful there for Jerry tones. Even with the volume on the pedal dimed and the gain way down (set to just above unity), the treble dimed, and the bass off, the pedal retained that classic Tubescreamer mids signature that is not what I'm seeking now. So back in the effects bin for the Drivetrain.
However, I did have some surprisingly good results with another experiement. I typically leave the gain on both my SMS and Fyd pre's at around 5. I'd fooled around when I first got them with different settings but once I settled on around 5, that parameter has remained for the most part steady. It wouldn't normally occur to me to boost the gain up to 7-8 because who in his right mind (except maybe Hendrix in the studio) would run a Twin Reverb at 8? But I tried it and I must say, I really liked what it did to my gain and tone. Adds a tad more grit/edge to the sound without morphing its basic overall character. I'm going to leave it this way for band practice tomorrow and see if I continue to like it at full band volume. In the interim, if anyone else would like to experiment with this and add your reactions to the thread, please do.
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