have thought long back and forth, the reviews, the www., Youtube etc. endeavor and my Fachsimpelleien to China, scrap, Watts, ohms, frequency, harmonic distortion and, and, and read and listened to !! This long until I believed today to buy a simple amplifier, I would have still an electrical engineering studies aim. Can surely not be true !! -> So ordered !! Delivery ... no problem !! A small package ... a small amplifier including cable ... a small instruction manual !! Quite logical Actually everything even for the novice !! So installation ... stop !! ... Still a Cable Lock 12V with 5 amps for 1.99 Einstecksicherung worried !! So mounting the 2nd ... extra battery (backup in between !!) ... Minus to ignition !! ... Otherwise there continuous current and the battery makes ratzfatz the opponent !! Speaker cables clean to put ... Chinchkabel infected (not doing !!) ... The voltage increases !! PS .: 2 x front speaker + 4 x rear speaker ... so far without amplifier ... Result pretty loud but dull and without proper surround sound !! So now ... Ignition on ... red LED lights amplifier ... Radio switches to ... and ... Wow !! -> As in the church !!!!! Volume control on the amplifier first turned back very brave !! and then times very slowly on a secluded parking lot tried everything ... Low / Off / High ... regulator out regulator ago ... radio, CD, iPod ... tried everything !! Conclusion: Brilliant sound in all registers !! Allen critics despite ... the thing is more than you think !! PS .: Habs now several months without Mullen and knullen in use, But beware, you have to remember that depending on the workload logically is the particle pretty hot !! for the purpose of installation !! - The glove compartment or in the knee area I would not mount degrees !! otherwise you can a can of ravioli warm or fetches blisters !! :) Oh one more thing ... the USB port I do not need ... can not say anything to !!