The following is from the LTA website.
"Can I use the MicroZOTL2 as a preamp for my DC-coupled solid-state amp?
The MicroZOTL2's preamp outputs were added by LTA (similar to how the headphone jack was added as an afterthought by Berning) just to see if this remarkable little amp could also make it as a preamp. To our surprise, though not surprisingly, it has emerged as an incredible preamp. Due to its genesis, however, it does not have all of the features of a typical preamp: most significantly, it does not have protection for the turn-on/turn-off thumps, which means that a DC-coupled amp could amplify these and damage the speakers. To avoid this, you must turn on the MicroZOTL2 before you turn on your power amp, and turn your power amp off before you turn off the MicroZOTL2. The MicroZOTL2 should therefore be the first thing on and the last thing off......"
Which is all well and good, however, if your power should go out (and back on, as happened to me) it can be unsettling or potentially dangerous to your speakers. It's not like the little thump one experiences when turning on some equipment. I'm saving up for the dedicated MZ preamp.