Surround sound smackdown: What's wrong with just plain stereo?

Linda Ronstadt should not sound like her head's in a bucket.

Reneé Fleming should not seem like wandered to the back of the orchestra.

David Gilmour’s guitar should not sound wimpy.

But depending on how your car stereo is set, they could all be like that.

Most cars these days offer name-brand sound systems, typically as an upgrade. It’s a trend that’s expanded from mass-consumer brands like Sony or Bose to more esoteric audiophile choices; we learned recently that venerable English speaker maker KEF is pairing with venerable English automaker Lotus. The partnership that got everyone’s attention is Jeep and hi-fi legend McIntosh, with the superb result you’d expect.

Vehicle sound systems now pump out hundreds of watts through a dozen or more speakers. (The new BMW 7 Series B&W setup has 36 of them!) So why, then, does car audio sometimes sound … kind of meh?

It might be because you have “surround sound” switched on.

I first realized this years ago when I owned a 2014 Toyota Highlander. Music through its JBL Entune system sounded mushy. Deep in the menus was a surround sound checkbox. Uncheck that, and a veil was lifted.

Until discovering that hidden setting, I hadn't realized the car had surround sound. And you might not be aware, either.

Let’s take a moment here to explain that what’s being called “surround sound,” or in some cases “3D” sound, is not the same as the 5.1 or 7.1 surround of your home theater. Movie soundtracks are actually recorded in surround, and your home A/V receiver can replicate that. But music, with rare exceptions, is recorded in stereo.

Surround sound in a car is something different. It’s signal processing — in which a stereo recording is not reproduced in two channels out of two speakers (or left-right sets of woofers-tweeters-midrange) as the recording artists and engineers had intended.

Why? Automakers and audio engineers believed they had problems that needed addressing. When listening to a home stereo, you sit in a sweet spot facing two speakers, and they stereophonically generate an “image,” aka the soundstage, that replicates what your two ears would perceive if you were attending a live performance. (At home, you can also employ that other music-enhancing device, a glass of wine.) In a car, however, no one can sit in the sweet spot. Never mind that even at home not everyone can sit in the one exact best chair.

Another challenge: A car interior is a small, sealed space with a weird mix of hard surfaces like windows and soft surfaces like occupants and seats.

So, using signal processing, engineers try to improve the listening experience throughout the cabin — even to create a “concert hall” feel. (One system is touted as replicating the "power" of a stadium concert. Now, when did you ever hear good sound in a stadium?)

Anyway, a more immersive sound is the intent. The trouble is, signal processing can compromise clarity.