Trace Elliot G-RP3 preamp
There are two versions: one also has built in effects, otherwise identical. 3 channels of well-balanced, i.e., great clean, smooth crunch and sustaining lead. Also has a convincing 'Metal' mode in channel 3, although I don't use this myself because of the music I do. Input gain for channel 1 and 2 is through a 12AX7; channel 3 is solid state all the way.
Footswitch offers footswitch access to channels 1, 1+2, 2, 2+3, or 3 only. 2 additional switches toggle the internal effects and a second activates an external loop device. The switches DO wear out; I've had 2 incidents of a switch going out - once during a live performance, and could have been royally fucked - but had a soldering iron at hand and replaced the switch in 15 minutes and all was dandy again.
Stereo XLR DI out: this has always sounded fine - not fantastic as a FOH only sound, but really opens up your sound if it's in addition to what's coming out of your stage amp.
No MIDI unfortunately, so unless you want to switch between different internal reverbs, delays on-the-fly (something I can't be arsed to do live), you are stuck with a single selected internal effect.
Built-in tuner. But strangely, it's always kaput (and I've seen 5 examples of the unit, own 3). Can't vouch for the quality of the tuner even if it is working.
2 additional 1/4" jacks on the rear panel allow connection of global volume pedal control, and a second volume pedal for 'crunch' control on channel 2 (withough affecting overall volume too much). Don't use these myself, but someone could.
Front panel is in the TE tradition of green illumination, and looks sweet on stage (doesn't really help you see the controls any better though).
I usually go into the FX return of the stage amp to bypass its own preamp.
Can be picked up for about 150 dollars used (they are about 15 years old).
A really well realised design, with some bells and whistles, but still straightforward enough to be a great live box.