Review on Compact and Powerful: Soundstream ST4.10000D 4-Channel Car Amplifier - 90WX4 by Matthew Henderson

Used this for a Kenwood aftermarket upgrade in my 2005 Jeep Wrangler Rubicon. Worked great! There's almost no room for anything in the Jeep TJ, so this compact amp was perfect. If you're wondering (like me) if/where to install this... *I was able to install it under the steering column. The speaker still has full up/down adjustment.* This arrangement protects it from direct water/splash as I drive the Jeep quite often (and tend to get stuck in the rain - thanks to the weatherman... )* Next to the clutch pedal where you can route the 4ga cable from the amp to the battery. The cheap Kenwood head unit that PO installed has a supposed 15 watt per channel amp that sounded awful. BUT it has very decent DSP control for the line level outputs. I chose this amp because I was looking for a cheap, super compact 4-channel amp and it worked for me. I've seen there's a Bluetooth version too, but that was more trouble than it was worth as the head unit already does the job. YMMV but I highly recommend it for my Jeep application.