Garnet's Guillotine is a tube based guitar preamplifier, designed to substitute the need for a tube amplifier. It's got two 12AU7 tubes in it, as well as 1/4" connections for input and output, as well as for a foot switch. The power supply is included with it, and it isn't rack mountable as it would take up about a third of a rack space.
The make up of the Garnet Guillotine guitar preamp is really easy to understand and to follow. There isn't much that you'll need to know before hand. It's got parameters for gain and output level, as well as a three band equalizer. Since it's so simple to use, a manual isn't necessary with the Guillotine.
The end result in terms of sound with the Garnet Guillotine is outstanding. It's absolutely got all the sound that you'd expect from a tube amplifier, as it's got a whole lot of bottom to it and a ton of sustain. You can use this with any amp or cabinet as far as I know, giving you that classic tube amp sound whenever you want it. There isn't all that much control beyond the equalizer, but this thing pretty much does all the work for you. I can't say that I'd take this over a real tube amplifier like my Fender Twin Reverb, but it's pretty darn close.
For those who are after a great tube sound at all times, the Garnet Guillotine will be your best friend. It's the perfect substitute to a tube amplifier, or even just great to have around if you're looking for a different color. I don't know too much about Garnet amps, but this thing is really awesome. The Guillotine is definitely worth a look for anyone that is a fan of the tube amp sound.