Can someone explain me for what is use this?
A regular amp is composed of a preamp, a power amp and speakers. That is just a preamp by itself. You would hook it up to a power amp and connect it all up to a cab to have yourself an amp. Some people like to mix and match independent preamps and power amps like that for flexability or to get specific sounds.
It basically is something that drives your amp even farther and makes it sound better. They also usually have multiple inputs for connecting other amplifiers or speakers. Most preamps contain controls for volume, bass, and treble, depending on the type of preamp( in that specific preamp, it also has controls for middle and level). And one other thing; preamps have no on board amplification.
Last edited by kutless999 at Jul 26, 2011,
it's one half of a complete amplifier. the preamp.