Blazing new car stereo equipment is heating up road trips everywhere.
It's not easy being a car audio engineer these days. You have to balance a fundamental commitment to sonic quality with consumers' ever-growing appetite for punishing sound. Add to that a shrinking amount of automotive real estate and the challenges multiply. Here's how some of today's top companies are responding.
Alpine's CDA-9815 CD head unit ($500) bundles a CD player that can spin conventional audio CDs as well as MP3 and WMA (Windows Media Audio) discs. To compensate for the loss of harmonics that occurs when music is compressed into MP3 or WMA files, Alpine adds a Media-Xpander circuit that boosts harmonic levels across all frequencies to make music sound live. The unit also has an AM/FM tuner and can accept the feed from an XM Satellite Radio add-on tuner.
The CDA-9815's 60 watts by four channels is considered high power for a head unit, although Todd Van Zandt, Product Promotion Manager at Alpine, notes that consumers should take all car-stereo amp ratings with a grain of salt since power can be measured and expressed in a number of ways. The CDA-9815 can reach 60 watts per channel at peak intervals, but its continuous power with low distortion is actually 27 watts per channel, compared with about 16 watts per channel for most amps. The 9815 also has three preamp outputs for add-on power.
Vehicle types and listeners' sound preferences vary widely so Alpine has added its iPersonalize feature to the 9815. You can boost or cut sound frequencies in the car to reduce unwanted resonances or to tailor sound to your taste. Another feature, digital time correction, allows you to control the arrival time of sound from the speakers so, for example, music from the passenger-side speaker can hit your ear at the same time as the sound from the driver side. You also can set the delay to make bass signals from a rear-mounted subwoofer arrive at the same time as the higher frequencies. The end result is a more cohesive sound. Alpine's iPersonalize Web site walks consumers through the process and allows them to store settings on a CD for uploading to the 9815.
The subwoofer plays a major role in today's car stereo. Driving bass lines in rap and rock music demand a big woofer that can reproduce frequencies well below the 100-Hz cutoff of most conventional car speakers. It's not just punchy pop music that benefits from low bass. Orchestral music and jazz are more satisfying when the full frequency range can be played back with ease.
Ironically, while vehicles have become bigger on the outside, the amount of interior space has shrunk. Until now, if you wanted a subwoofer box in an SUV or minivan, you either had to relinquish storage space or mount a 6-in.-deep speaker into a 2-in.-deep door panel. Blaupunkt's OverDrive ODw1200 Saucer subwoofer ($299) solves that problem. The Saucer is half as deep as conventional 12-in. woofers and can tuck into spots where other subs can't go.
Tom Breithaupt, Engineer and Product Manager at Blaupunkt, calls the Saucer a nice compromise because it reproduces low bass by combining a large cone with a shallow cone. As a result of the shallow depth, the woofer can easily fit into a side door, kick panel or center console. Blaupunkt recommends using the Saucer with a 200-watt amplifier and doubling the subs and amps to achieve the deepest lows down to 20 Hz to 30 Hz.
Amplifier makers also face space constraints--thus, multichannel amps are a good fit in most vehicles. JL Audio's model 500/5 5-channel amplifier ($900) shoots 100 watts to the left and right front speakers, 25 watts a side for "fill" to the rear speakers, and a beefy 250 watts to the subwoofer channel.
The JL 500/5 features the company's Regulated Intelligent Power Supply (R.I.P.S.) system, which delivers the same power regardless of the impedance, or resistance, of the speaker it's matched with. "That gives consumers all the power they paid for," says JL Audio President Andy Oxenhorn.
The amp is a hybrid design. It uses a Class AB amplifier, which has superior sonic performance but gives off a ton of heat, for the front and rear speakers and a Class D amp, which is more efficient by nature for the sub channel. The hybrid approach brings audio fidelity to the sonically critical mid and high frequencies. At the bass level, where sonic performance is less critical, the Class D amplifier runs cooler, requires a smaller heat sink and can fit into a smaller space.
Many head units tout high power, but typically those specs measure peak levels and don't include distortion measurements. JL's power specs represent low-distortion power at continuous levels. If you try to push a typical head unit to its maximum power level, you hear a flapping or warbling sound because its amplifier can't sustain that level for extended periods. An add-on amplifier like the 500/5 gives you space to crank up the volume without producing the distortion of an overtaxed system.
Consumer demand for volume puts pressure on speaker companies too. "The biggest thing the consumer wants to do is to play his system louder," says Chris Dragon, Director of Car Audio Brand Marketing for JBL. "Engineering speakers that will play loud yet maintain sonic decorum is one of the big challenges we face."
JBL's P652 loudspeaker ($230 a pair) uses its Plus One cone technology, which has enabled engineers to increase the size of a cone while fitting it into a standard-size enclosure. A cone on a typical 6-in. speaker is actually about 5 in. in diameter, says Dragon, but JBL retooled the cone's housing to fit a 5.75-in. cone in the same amount of space. "More cone area means more bass output, higher efficiency and less power required to drive them," he says.
Like many of today's speakers, the JBL P652 features a pivoting tweeter, allowing installers to control the direction of the high frequencies for better stereo imaging of the left and right speakers. JBL's ratchet design holds the tweeter in place during bumpy rides.
If CD head units, amps and speakers are the foundation of car audio, hard-disk audio players are the way of the future. Rockford Fosgate's OmniFi offers a glimpse of the custom entertainment options to come. OmniFi lets you download music and other audio programming from your PC and bring it into your car. You'll still use your head unit for control and CD playback, but the OmniFi 20GB hard-disk recorder gives you a daily refresh of music and Internet audio.
Tom O'Mara, Managing Director of OmniFi, sees this product as the great liberator of consumers' music collections. "People have these great libraries of music on PC but that's not where they listen to music," he says. "We used to be limited to a 10-disc changer and awkward navigation in the car," he says. "Now you can get text information about the music, and you have access to thousands of tracks."
For 'burb dwellers, the OmniFi never has to leave the car if the receiver is within 150 ft. of the home PC, because the unit packs an 802.11b wireless receiver that can network with the PC. Or, you can remove OmniFi from its car dock and connect via USB to a PC. With the OmniFi service, you schedule a sync to occur each morning, and music you've stored in a queue--along with news or sports updates--is downloaded to the unit.
The OmniFi system--including the player, housing, cables and a dash-mountable controller with 3-line LCD readout--is priced at $599. A subscription for news feeds is $5 per month, or $50 a year.
Tired of the same old factory radio? It's time to pump up the volume and take your tunes on the road.
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