Check the listing for details. Alpine KTA-450 50W x 4 Compact Amplifier. Condition: New. Listed at 219.95 USD. Product highlights4-channel car amplifier 50 watts RMS x 4 at 4 ohms (45 watts RMS x 4 at 2 ohms) 100 watts RMS x 2 bridged at 4 ohms CTA-2006 compliant Dynamic Peak Power (DPP) technology adds a burst of power when needed selectable high-pass filters (60, 80, 120 Hz at 12 dB/octave) on front and rear channels preamp and speaker-level inputs selectable 2- or 4-channel input PowerStack bracket included for mounting amp behind Alpine iLX-W650 digital multimedia receiver (#500ILXW650) wiring, hardware, and fuse not included with amplifier 12-gauge power and ground leads and a 20A fuse recommended dimensions: 7"W x 1-3/8"H x 3-9/16"D warranty: 1 year What's in the box4-Channel amplifier 12" Input/Output/Power harness 1 Head unit (iLX-W650) mounting bracket 2 Universal mounting brackets Four M5x6mm Allen head machine screws (3mm) Two M2.6x8mm Machine screws Four 3/8" Screws Four 7" Zip Ties Owner's Manual (English/ French/ Spanish) Warranty information On-line product registration information About this itemWritten by Crutchfield's Buck PomerantzBump up the power If adding more power makes music sound better, Alpine's KTA-450 power pack will make a significant improvement in your system. This compact 4-channel amplifier puts out 50 watts RMS per channel from a tiny chassis that'll fit almost anywhere in your vehicle. KTA-450 uses Alpine's Dynamic Peak Power (DPP) technology to deliver a quick energy boost when needed, virtually doubling the amplifier's output power on musical peaks. PowerStack Installation Here's a very cool idea from Alpine — the package includes a PowerStack bracket for mounting the amp in your dash behind Alpine's shallow chassis iLX-W650 digital multimedia receiver. The combined depth of receiver and amp is still less than 5", so it'll fit in a wide variety of vehicles. The receiver and amp together make a feature-filled and powerful sound system that you'll enjoy for many miles. Installation Notes: This power pack will not work in systems with a factory amplifier. Wiring and fuse are not included — 12-gauge power and ground wires and a 20A inline fuse at the battery are required. PowerStack bracket with KTA-450