Speed Kills: The Crucial Role of Speed in High-Quality Subwoofers

Making the Best Subwoofer Decision for Your System

In athletics, the phrase “Speed Kills” refers to the advantage that teams with superior team speed hold over their opponents. For REL subwoofers, the incredible speed and reactivity our designs deliver is an advantage we hold, but it’s available to all.

Speed, Extension, and Output–in that order– are the differentiating factors when considering which of our families of products your system will most benefit from. Serie T/x (music forward) and Serie HT (theatre forward) both possess far above-average speed and, for many, will be all the subwoofer that they need. Certainly, our latest HT MKII models can deliver the deep bass, speed, and output levels competitors largely can’t deliver, at least at our prices.

The question becomes, when to step up to Serie S, and is that step worth it? We’ll answer that and explain our Subwoofer Finder method for arriving at those recommendations.

First, Speed:  We begin with speed because nothing brings long-term enjoyment of the entire listening experience down faster than a subwoofer that lags just a tiny bit. It’s like wearing heavy boots in Summer; you can do it but why would you want to?

I’m going to use two very different Bowers and Wilkins loudspeakers to illustrate the differences between the need to migrate upward from Serie T/x to Serie S. In the first instance, their excellent model 700 S3 runs $7,000 here in the U.S. Meanwhile, their 805 D4 will set you back $8500. Perhaps surprisingly, given that it is the larger floorstander of the two, the 702 S3 is the one that we recommend the Serie T/9x ($1449), and the model 805 D4 gets the nod for the far more powerful REL Serie S/510.

Wait, are saying that you CAN’T use an S/510 with my 702 S3? No, simply that our first criteria speed doesn’t demand its use—plenty of folks have purchased S/510s—even pairs of them to go along with their 702 S3. The 702 range represents a well-designed, somewhat sporty family sedan – perhaps a Honda Accord Sport model. It does pretty much everything well, and is a solid all ‘rounder. Mated to a REL T/9x, you have a well-balanced system, that does pretty much everything you could ask of it for the money. Whereas a model 805 is a Porsche Boxster. It’s not for everyone, it’s designed to carve backroads, and doesn’t carry as many people. It’s not the fastest in a straight line (loudness/output) but far more interesting than any mere sedan could be. And that perfectly describes the S/510 except that it also plays remarkably loud and can sound huge if called upon to deliver…so there goes the analogy.

The more interesting question is “Why the S/510 for the 805D4”? The Model 805 goes back some 30+ years in various iterations and has always been Bowers and Wilkins’s choice for a musical stand-mounted speaker for those who are well-heeled but choose to live in smaller quarters. Think London pied a terre, you’ve given the butler the night off and told the chauffeur he won’t be needed as you’ll be staying in tonight to spin the latest vinyl.  OK, you’ve actually ordered Chinese takeout, and while you’re waiting for Uber eats to deliver it, you start streaming Qobuz on your recently updated system. C’mon, work with me people!

Speed is the defining characteristic of the S/510. Yes, it checks all the usual big-boy subwoofer criteria; it goes down into the lower 20-30 Hz region, and its output peaks somewhere in the 108 dB range (very loud). But most subwoofers that meet this description aren’t possessed of its suppleness, its ability to mate perfectly with infinitely fast electrostatic speakers, or ultra-expensive monitors like the Franco Serblin Accordo. Nope, they sound like conventional subs. Big, a little heavy sounding, and just a tad ponderous, dark, and slow. Whereas a fast monitor-style speaker like the 805 is quick, alert, and alive. As is the S/510. And the S/812 does the same for larger-scale, but still fast, speakers and so on up the range. The Carbon Special makes you think “That must be the finest subwoofer ever designed”. And it’s true until you hear a No.31.

Why the differences between these REL families?

It comes down to our goals for the two and therefore the available budgets our design team can throw at the design. Just as it does for your speakers. The S/510 costs some 60% more than a T/9x. But it delivers things no Serie T model could dream of. And, importantly, those benefits don’t stop at the bass. Where most subwoofers seemingly bow out of the conversation by 100Hz, the S/510 has the capacity to open up fast loudspeakers, many of them costing upwards of $20,000, and improve the very things they’re best known for. Image precision, rhythm, nuance, harmonic structure, and air…all improve vastly when the sub matches speaker speed.

So, there you go.  I hope that explains the differences in goals and performance achieved when stepping up from Serie T/x to Serie S. Thanks for reading!  We write these articles to provide ongoing education to the broader community I – everyone who loves music that’s brilliantly presented, as well as film sound that draws you into the movie. Also, we aim to deliver this quality sound fora vast range of budgets. We will always take great care of the little guy, but we also will take the ultra-high-end experience farther than those lucky owners can imagine.

November 28, 2022 - Posted in: Principles of Sound