You know what they say about good things coming in small packages? That adage now applies to specialty car-audio equipment, because the latest amplifiers are smaller and more versatile than ever before. New class-D amplifiers are small enough to fit in most center consoles (rather than in the trunk or under your seat). One manufacturer says its smallest amp, which is so new that it hasn’t even been assigned a class, even will fit behind the dashboard. Plus, manufacturers say they have solved a notorious noise problem that has been associated with the class-D amp, which allows such an amp to be used for the entire speaker system (rather than just for subwoofers).
Meanwhile, if you want to make your factory vehicle stereo sound even better, you should know that there’s a new microphone technology for the digital-signal-processing (DSP) feature that’s on premium original-equipment-manufacturer-integration products. OEM-integration products allow you to keep your factory audio receiver (or head unit) but add amps and other components to your audio system.
Class-D Confusion: It’s Not a Digital Amp
SIZING UP AMPS. The reason why full-range class-D amplifiers can be as much as half of the size of traditional (class-AB) models is because they produce less heat. Manufacturers tinkered with the built-in power supply technology to make class-D amps highly efficient, so they draw less power (and generate much less heat) than do class-AB amps. If you buy a full-range class-AB amp today, you can expect to get something that’s, on average, the size of a large dictionary. The size and the ventilation requirements of a class-AB amp mean that it almost always has to be installed in your trunk. However, a full-range class-D amp (capable of powering all of your car’s speakers, not just a subwoofer) is roughly the size of a paperback novel and can produce up to 600 watts of power. The smallest full-range class-AB amp that has similar power ratings is nearly twice as large.
Unfortunately, the only thing that isn’t smaller about full-range class-D amplifiers is the price. The average MSRP of a full-range class-D amplifier is $518, which is $300 more than the average MSRP is for the class-AB models that we evaluated that have similar power ratings.
So why would you want to pay so much for an amp that’s so small? If the amp is small enough to fit in your center console, or in another small compartment inside your car’s interior, you won’t have to mount it to the back of a rear seat or someplace else in the trunk where there is room for proper ventilation. And if you do choose to install a class-D amp in your trunk, it will fit in just about any nook or cranny that’s back there.
And get this: Rockford Fosgate says it will introduce a full-range amp this year that’s even smaller than the smallest class-D amp is. It’s so small, in fact, that it will be able to be mounted behind the dashboard of your vehicle. The company originally designed the amp as a single-channel design (for powering only subwoofers) and a factory component for automakers. But in January, the company announced that it also would create an aftermarket version. Although product specifications weren’t available at press time, Rockford Fosgate tells us that the cost and power of that full-range amp will be comparable to the $200 single-channel version of the amp (PBR300X1) that’s on the market, which also fits behind the dashboard of some cars. The PBR300X1, however, is designed to work with only subwoofers, making it similar to the first class-D amplifiers.