+1 to Marty.
I should have experimented with the rear trim pot long ago (instead, I set it on 1 o'clock when I received my SMS and never moved it once until over the past hour of experimentation).
Here's what I've found - these are empirical findings, not assumptions (though, of course, my hearing or judgment could one or both suck, in which case it's all useless anyway
1. Adjusting the rear trim pot has a very significant impact on all of volume, tone, and dynamics.
2. Cranking the pot up full or close to it both increases the overall volume and the guitar and amp's treble response. I.e., like volume pots on many guitars that lack treble bleed pots, I'm hearing more treble as the rear trim pot is upped to the point where, full on, I'm hearing an almost piezo like brittleness to the tone (that's just my word for it - others may characterize it differently and/or dig it).
3. With the rear trim pot up high and the gain high on the SMS, it is no longer a pure "clean machine." Just as Hendrix recorded searing leads in the studio through a cranked Twin Reverb, you can get plenty of crunch - more than than you might have thought you could - out of the SMS this way. (I.e., it's a far more versatile unit than may appear at first . The unit cranked would be a wonderful
4. But, with the rear trim pot up higher AND the front gain control lowered (say to 9 or 10 o'clock), you can get a very rich tone that is harmonically complex yet remains clean (if I'm interpreting Marty's post correctly, this is what he's found, too).
5. My Jerrycaster has a split Super 2 in the middle position. Through it, I ended up liking best the rear trim pot at around 3:15-3:30 and front gain control at around 10 o'clock. I think I'll keep it there at least for band practice tomorrow to give it a fuller workout and will report back if I make further changes.
6. At these adjusted setting, NOW I'm grokking Brad's and Mike's baseline/preferred settings of treble at 85%, mids at around noon, and bass off - the added girth from upping the rear trim pot makes the difference for me.
7. Lastly, I found the reverb fuller and lusher sounding after I upped the rear trim pot. I had to lower the control some afterwards to compensate!
The quest after tone is a harsh and jealous mistress but you get by with a little help from your friends. Thanks again to everyone contributing to this thread as once in while ...