Found this, written by Miles a while ago: There is a feature of the THD Univalve that is overlooked by too many folks. This is something I have written in the past that may be of value to some UV owners. You might also want to try the line out of the UniValve to feed the instrument input of your current amplifier. The UniValve is one of the most impressive recording tools available, as well as a superb front end for amplifiers in a performance venue. Mic'd up with its own cabinet and mixed with a signal into the house system is something to be heard ... you won't forget the experience. This is one of the biggest features of this amp. It is overlooked by too many folks. If you have a clean amp that you thought was rather one dimensional (as an example, a clean Fender Twin), using the UV as a preamp will yield fantastic results. Plug your guitar into the UV, and take the line out from the UV using the instrument setting, plug into the Fender Twin input. Now you can set your volume on the Fender Twin to the desired loudness level, set the UV's volume to the desired clean, crunch, or distortion taste, and then balance the overall level using the UV line out level pot as to keep from overdriving (unless you want to) the front end of the Fender. The UV sits quite nicely on the top of most amps. You do not need to even have a speaker hooked up to the Univalve, it has built in protection when a speaker is not connected. I do not think of the Univalve as a guitar amp. I do not try to compare it with other amps. It is a great amp of course, and is quite loud in spite of it's published ratings, but this amp is a MUST HAVE tool for the studio. It is a fantastic unit to use with ProTools or other direct recording Digital Work Stations. If you have a budget for amps and another for studio gear, maybe take a little out of each for a Univalve.