That's cool man...Really, both of my "big" amps sound pretty decent at low volumes, but it's really hard to control myself sometimes, as I do like it a little louder than most...hahahaha....
It's weird how differently my 2 amps react to their master volume, the DSL must be pretty similar to your JVM as the power tubes really don't add anything to it that it doesn't already have at low volumes, but the Ceriatone gets dirtier the louder you push it...After about "8" on the Chupa's master, it just fuzzes out too much for me really...about 7-8 on the master of that amp is "it" for me...
Just to be honest, I very rarely push
the DSL100 past 4-5, that's just super-fuckin'-hurt all over loud, but the few times I have cranked it up, the power tubes add just a little grit when you hit about 7 or so on the volume, but again, man that is super fuckin' loud...
Believe it or not the little 1w DSL's power section adds some breakup when you get it wound up to about 7-8 too...It does sound pretty good through my 4x12 with the SD-1 boosting the red channel & will actually suprise you how loud it is for a baby-version 1 watt amp though...

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And the more I play either of these amps, the more I like 'em...I had the Chupa on tonight, just basically dicking around with it, & I have to say dude, it's great...The era switch on that thing make it a dream come true for me, more gain than I'd ever need, with lots of options for different tones with the bright switches (these are technically bright switches, but they really add pre-amp gain, just a little different "flavor" with each position)...I know it's not a real plexi/super lead, but I'm really happy with it myself....
Fuck man, I'm pretty happy with all the gear I've got to be honest....

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