PERFORMANCE

Fatigued after spending 3 hours moving subwoofer modules around, I vowed to put off my listening tests until the next day. But my plans changed when the Bottle Rocket Blu-ray Disc arrived from Netflix that afternoon. Eager for some light entertainment, I fired the system back up and settled into my couch. I didn't expect to glean any useful information about the BGX-4850 by watching this low-budget indie flick, but I did. Bottle Rocket features a loungy soundtrack by Mark Mothersbaugh, the Devo frontman turned film/ TV composer.

Through the BGX-4850, the music's melodic bass lines sounded perfectly even, with a tight, punchy groove that reminded me of what I've heard in Los Angeles's best recording studio control rooms. The character of the bottom end differed dramatically from the "full of 50-hertz fury, signifying nothing" bass one so often hears in home theaters. My experience with Bottle Rocket inspired me to switch right away to stereo music. The bass lines on my favorite reference CDs sang, with no unnaturally booming notes. Even though the timing of the notes was the same as with any other sub, the BGX-4850's smooth response seemed to improve the rhythm of the tunes I listened to. And it delivered this superb performance in every seat across my couch - something no single subwoofer has ever been able to do in my system.

The great sound on Bottle Rocket told me nothing, though, about the performance on real movies like Final Destination 2 and Hellboy. All of my favorite test scenes - including the brontosaurus stampede from King Kong and the spaceship flyover that begins Star Wars, Episode II: Attack of the Clones - sounded brutally powerful yet precisely defined, as if I'd arrayed four or six top 12-inch subwoofers across the front of my room. Midbass sound effects like punches and kicks came through with dramatic impact; the experience was almost uncomfortable.

Here's the rub, though: When, just out of curiosity, I tried going back to some of the other subwoofer positioning schemes I had tried, in every case the low bass practically disappeared. The system suddenly sounded thin and unbalanced when I played slam-bang action movies and heavy rock music. Those little woofers seem to need careful positioning (or perhaps some post-installation electronic tweaking) to work in concert with one another and your room. To get the most from the BGX-4850, you need an installer who's knowledgeable and who cares.

BOTTOM LINE

With careful installation and adjustment, the BG Radia BGX- 4850 is almost a holy grail of subwoofers. It practically vanishes into your walls; it delivers better punch and pitch definition than any 15- or 18-inch subwoofer I've heard; and in the hands of a good installer, it can deliver a truly thrilling, high-impact home theater experience. Even though it'll be hidden in the walls, its sound will grab your attention as much as anything Maserati or Movado could dream up.