Clean, Bright Sound from the Best Car Amplifiers

Considering the fact that the ‘Power’ series of amplifiers are Rockford Fosgate’s flagship offerings, you get a lot for your money with the Power T400-2. From the first glance, you can tell that the designers at Rockford Fosgate sweated the details, from high-quality connections (to reduce quality degradation at the connection) to the wrap-around heat sink with dynamic thermal management technology to reduce distortion-causing hot spots on the amplifier body. The Power T400-2 is capable of impressive power levels, from 120 watts RMS to 2 channels at 4 ohms, 200 watts RMS to 2 channels at 2 ohms, to a whole 400 watts RMS in bridged mode at 4 ohms. The circuitry inside this amplifier features advanced algorithms designed to eliminate distortion and interference, and the differential input design ensures that there is no cross-contamination between the signals. As is fitting for a flagship model from a company like Rockford Fosgate, this is a highly capable, reliable amplifier that shows no real weaknesses to speak of.

Focal is renowned for its high-performance products, and the company's amplifiers are no different. The FPS 2160 puts out 105 watts RMS per channel at 4 ohms, 180 watts RMS per channel at 2 ohms, and 360 watts RMS bridged at 4 ohms. While the output is exceeded on paper by numerous competitors, the FPS 2160 easily outperforms them all in the real world. The thermostat-controlled cooling fan and heavy heatsink ensure cool operation, and an optional capacitor module can improve power efficiency. The FPS 2160 features algorithms that can clip signals on demand to reduce distortion, and signal paths have been designed specifically to maintain sound fidelity and minimize external interference. All of this attention to detail comes at a price, however - it's definitely expensive, and will appeal to a limited group of enthusiasts.

The Alpine PDX-F4 proves that not all powerful amplifiers have to come in giant sizes. This particular amplifier is of a Class-D design, which means a smaller overall package is possible while keeping high power output levels. The dimunitve size of the PDX-F4 hides the fact that this amplifier puts out 100 watts RMS per channel, whether set up with 4 ohm or 2 ohm impedance ratings. Bridging the outputs yields 200 watts RMS through 2 channels, which is suitable for connecting subwoofers. If your car or truck is tight on space, Alpine designed these amplifiers to be stacked on top of one another, thereby saving even more space than comparable 'compact' amps.

First and foremost, Focal produces only high-end audio products. The FPP 1000 does not disappoint, offering outstanding performance combined with unique features. Lots of control over bass settings make the Focal FPP 1000 stand out from the crowd. This Class-AB amplifier has a variable low pass filter, a subsonic filter, variable bass boost, and a less-commonly seen phase switch along with an included wired remote for level control. A heavy aluminum chassis disperses heat, so shut downs and interruptions become an absolute rarity. With output of 300 watts RMS at 4 ohms, and 500 watts RMS at 2 ohms, this amplifier has plenty of power to drive one or two subwoofers with authority. Differential-balanced inputs help eliminate noise, ensuring that sound will always be clean and free of distortion. With lots of performance and the ability to fine tune your bass to just how you like it, the Focal FPP 1000 is a great choice.

Focal already has a well-deserved reputation for producing only top-quality products, so the inclusion of a 2-channel Focal amplifier as a 'high-end' pick should be expected. This rather serious-looking 2-channel amplifier pumps out a stout 155 watts RMS through 2 channels when connected to 4-ohm impedance speakers, with output rising to 265 watts RMS with 2-ohm impedance drivers. Bridging the connections will net 530 watts RMS at 4 ohms and 750 watts RMS at 2 ohms - more than enough to extract heavy bass from a suitable subwoofer. The chunky cooling fins and active fan cooling ensure that the amplifier stays cool, and the FPS 2300RX supports Focal's 'High Cap' plug-in capacitors if more power is needed for heavier hits. As well, the FPS 2300RX carries Focal's traditional high price tag, so consider this amplifier only if you're building a true audiophile-grade sound system in your car.

While Kenwood's amplifiers may not benefit from the same sort of reputation enjoyed by Rockford Fosgate or JL Audio, the company is known for producing quality products. The Kenwood KAC-1502S puts out 60 watts RMS per channel at 4 ohms, 75 watts per channel at 2 ohms, and 150 watts RMS at 4 ohms when bridged. Even without factoring in the low price, this performance is consistent with its direct competition. Despite its Class-AB design, this amplifier is quite compact and can easily fit in most places in your vehicle. Setup is easy with speaker and preamp level inputs, while a fixed low pass filter allows you to have more control over bass output. While these more affordable amplifiers tend not to have quite as much longevity as more expensive ones, the Kenwood KAC-1502S offers a compelling combination of good power and quality for a low price.

The Focal FPS 1500 delivers 320 watts RMS at 4 ohms and 550 watts RMS at 2 ohms, which is already lots of power. However, it is also 1 ohm stable, delivering 800 watts RMS at this low-impedance load. An optional High Cap outboard capacitor module increases power efficiency, but either way, this amplifier delivers clean and powerful bass without interruptions. There are also enough controls to tailor sound, with variable low pass filters, a switchable subsonic filter, phase switch, and variable bass boost up to 9dB. As with Focal's other amplifiers, the FPS 1500 boasts the ability to clip signals in real-time to prevent distortion and damage. The cooling fans are controlled by a built-in thermostat, and the heavy heat sink helps keep components running cool. With excellent sound fidelity, minimum interference, lots of power, and plenty of features packed into a reliable and compact package, the Focal FPS 1500 is a stand out amplifier.

Alpine's PDX-series amplifiers are well-known amongst enthusiasts for their ability to provide lots of clean power from a tiny package. The PDX-M12 represents Alpine's flagship mono amplifier, capable of putting out at least 1200 watts RMS at 4 or 2 ohms. Each amplifier comes with its own 'birth certificate' which displays the actual power output of that particular unit as measured by Alpine - most units put out more power than the advertised norm. Despite being a 'Class D' amplifier, Alpine has put painstaking research and development into ironing out distortion and maximizing the frequency response range, making the PDX-M12 a top choice for audiophiles. As with the previous-generation PDX amplifiers, the PDX-M12 can be stacked atop other second-generation PDX amplifiers in order to save space and maintain a clean installation.

JL Audio’s HD series of amplifiers represent the best that this company has to offer. According to JL Audio, the HD900/5 is the result of combining two of their excellent Slash v2 amps: the 300/4v2 and the 500/1v2. The result is staggering performance, with all of the intelligent and convenient features that you find on the Slash v2 amplifiers. Versatility is the name of the game here, with different output levels designed to match voltage and impedance. You get 100 watts RMS through 4 channels at 4 ohms, or 75 watts RMS when the impedance is lowered to 1.5-3 ohms. The remaining channel receives 500 watts RMS at anywhere from 1.5-4 ohms, so you can be assured that your subwoofer will be suitably loud. Bridging the outputs nets 150 watts RMS through 2 channels from 3-6 ohms, and the ‘subwoofer’ channel remains unchanged in output. The HD900/5 is packed full of JL Audio’s best technologies, from high- and low-pass filters that you can adjust to eliminate the frequencies that your speakers cannot work with, preserving sound quality. The differential-balanced inputs separate the audio signal cables from the chassis ground, so your speakers are not muddled with background noise. Though the price may seem steep, this is easily one of the better amplifiers if you can spring for the price tag.

The Focal FPP 5300 can be used to power 5 channels, or bridged into 2-channel mode to power your front speakers and your sub, bypassing the rear speakers altogether. With a regular setup, power output is 60 watts RMS x 4 and 160 watts RMS to the subwoofer at 4 ohms, or 200 watts RMS x 4 and 300 watts RMS to the subwoofer at 2 ohms. When bridged, output rises to 200 watts RMS per channel (x2) at 4 ohms and 300 watts RMS to the subwoofer at an impedance of 2 ohms. The heavy aluminum chassis disperses heat to make sure this amplifier will stay reliable - even with hard use. Variable high and low pass filters, as well as a variable bass boost and subsonic filter on the subwoofer channel allow for customization of the output. The Focal FPP 5300 delivers a powerful, natural sound, and lots of setup versatility - all of which justify the higher price compared to other 5-channel amplifiers.