Rockford Fosgate's RFPEQU universal Punch EQ restores the sparkle and impact to your music that road noise usually covers up. Developed over thirty years ago for their popular Punch amplifiers, Rockford Fosgate now brings you this handy remote EQ system in a universal, stand-alone version.

Clarion's EQS755 boasts 7 bands of equalization that'll allow you to fine-tune your sound, along with independent master volume, subwoofer level, and fader controls that'll keep your highs and lows in balance.

AudioControl's legendary Epicenter bass processor maximizes the low-frequency power and punch of your bass system, whether it's a simple powered tube or a full-blown competition setup. Simply install this processor between your car's receiver and your outboard amplifiers, and hear what you've been missing.

This versatile 2-channel equalizer features 13 bands of adjustment for sonic fine tuning, along with level controls that allow you to match any receiver to any amplifier. And speaker-level inputs allow you to connect the EQL to just about any car stereo, even to factory amps up to 400 watts.

Kicker's Front Row digital signal processor puts your music where it should be right up in front of you. A wired remote control panel lets you center the music to your listening position, add bass, and engage a simulated 5.1 Surround Sound that makes it seem like you're at a concert.

AudioControl's FOUR.1i equalizer takes the old-school in-dash EQ to a whole new level. This little problem solver features 4-band equalization, a parametric bass equalizer, and a built-in line driver that'll send a hot, clean signal to your amps.

AudioControl's LCQ-1 six-channel signal processor lets you bridge the gap between your factory stereo and the high performance power of aftermarket amplifiers, speakers, and subs.

AudioControl's LCQ-1 six-channel signal processor lets you bridge the gap between your factory stereo and the high performance power of aftermarket amplifiers, speakers, and subs.

AudioControl's THREE.2 is an in-dash equalizer and a whole lot more, allowing you to control almost every aspect of your receiver's output from the driver's seat.

Kicker's KQ30 30-band equalizer will help make your music sound awesome in your car. Let's face it, your vehicle's interior is not the best place for listening. The limited and uneven space, echo-producing windows, and loud road noise combine to create "hot spots" that hurt your ears and dead zones.

AudioControl DQDX features a 24 dB/octave Linkwitz-Riley alignment crossover. This sophisticated crossover offers a flat response without any peak or dip around the crossover frequency and avoids the phase irregularities of lesser crossovers.

AudioControl DQDX features a 24 dB/octave Linkwitz-Riley alignment crossover. This sophisticated crossover offers a flat response without any peak or dip around the crossover frequency and avoids the phase irregularities of lesser crossovers.

Rockford Fosgate built their 3Sixty.3 processor so you can enjoy amazing sound quality from your vehicle's sound system — the quality you'd expect from a high-fidelity home stereo system or a pair of really good headphones.

Alpine built the PXA-H800 digital sound processor for one purpose: to deliver pristine sound to aftermarket amps, speakers, and subs. It takes control over your sound before you send it to an amplifier, stripping away hard-coded factory settings and starting from scratch.