Description of S-A55V:

Alpine introduces the all-new S-Series amplifiers - a perfect match to the S-Series speakers. These amps have an excellent Watts-per-Euro ratio in the Class-D category, feature a very high heat resistance and won't shut down due to overheating. They also feature excellent sound quality in their price range. The S-Series amplifiers are available in mono, 4-channel and 5-channel configuration.

Description of RWK42:

The Rockville RWK42 4 AWG (American Wire Gauge) amp kit has the following diferences over other amp kits on the market at this price point. Our RCA cables are 100 % copper. These are top of the line RCA cables Better Resistance: The only thing that really matters with wires is the resistance rating.

Description of RUX-KNOB.2:

The optional RUX-KNOB.2 remote bass control knob plugs right in to select Alpine amplifiers for quick direct subwoofer control to make bass adjustments on the fly. COMPATIBLE MODELS FROM THE INSIDE With the RUX-KNOB.2, get full control over your Alpine amplifier, conveniently from inside the car. With the RUX-KNOB.2 installed inside the vehicle cabin, easily adjust the bass gain of your amp while seated inside.