PLAYBACK: BG Radia BGX-4850 THX Ultra2-certified subwoofer system

Breaking All the Rules

About two years ago, I got a call from THX’s PR representatives asking if I’d like to take part in a briefing on the world’s first THX Ultra2-certified in-wall subwoofer system. Core technologies for the system, I was told, were being developed by THX chief scientist Laurie Fincham (perhaps best known for his achievements as the former Technical Director for the British speaker-maker KEF), while the resulting subwoofer system would be manufactured by BG Radia, of Carson City, NV. I was eager to learn what Fincham and BG Radia would do when given the freedom to create a world-class sub, so I signed up for the briefing and was soon introduced to a radical new woofer system design that breaks all the established rules, and for all the right reasons.

Let’s play a word association game. If I say “state-of-the-art subwoofer,” what thoughts first come to your mind? My bet is that you are picturing a big, honkin’ precision-made woofer (or two) loaded into a beefy, bank-vault-like enclosure and that is powered by a take-no-prisoners amplifier with enough output to propel a hybrid car. Well, apart from the amplifier part of the equation, let me tell you that the BGX-4850 subwoofer system ($6995) is nothing like that.

Flying in the face of tradition, Fincham and the BG Radia team have developed a multi-component woofer system comprised of four extremely compact yet very high output in-wall woofer modules that are—get this—inherently vibration canceling, plus an outboard controller/amp module to power them. Interestingly, Fincham never saw the in-wall aspect of the system as a performance-limiting factor. On the contrary, he felt the size constraints of an in-wall sub compelled him to think—quite literally—“outside the box” to create new woofer technologies that offer a fundamentally better-sounding way of reproducing bass frequencies. To appreciate the true character of this BG Radia woofer system, then, don’t think of it as an in-wall product, per se, but rather as a world-class sub that also just happens to support in-wall mounting.

Specifically, the BGX-4850 subwoofer system is meant to address five specific design goals:

• Provide THX Ultra2-certified output capabilities.
• Achieve well-distributed and extremely evenly balanced bass response throughout the listening room.
• Deliver excellent low-frequency extension with exceptionally fast transient response, great pitch definition, and terrific timbral purity.
• Achieve all of the above in a compact and virtually invisible in-wall format.
• Achieve all of the above in a design that cancels out woofer cabinet vibrations, thus minimizing problems with resonance and vibrations in wall studs and/or sheetrock panels (problems that can crop up with high-output subs of any kind).

As the THX/BG Radia press briefing came to a close back in 2007 I expected that a production-release version of the BGX-4850 system would appear within a few months, but it was not to be. When manufacturers are chasing state-of-the-art performance it can take longer than you’d think to get those final few product details just right, which was certainly the case with BG Radia’s new super woofer. Trade shows came and went yet the final production version of the BGX-4850 system remained tantalizingly beyond reach—until just recently. But as you’ll see in a moment, it was worth the wait.

OVERVIEW 

Consider this subwoofer system if: you judge subs by their sound, not by their looks. (BG’s system looks fine, but—in in-wall form—is essentially invisible). This system performs exactly as advertised; it provides high output, deep bass extension, lightning fast transient response, great pitch definition and timbral purity, and evenly balanced bass output all over the room. Unorthodox though it may be, this is one of the two or three best subs I’ve heard at any price.  

Look further if: you want massive “trophy subs” to show off to your buddies (the BGX system duplicates the output of two conventional 18-inchers, but is low on “bling factor”). Look further, too, if you are cost conscious or require an in-room solution (BG’s in-room enclosures won’t be available ‘til later this year). The only serious omission is lack of a built-in room/sub EQ system—a touch we would certainly expect in a woofer system in this price/performance class.