REL Serie R-528SE Sub-Bass System


Equipment report
REL Serie R-528SE Sub-Bass System

In my opinion, a better way to set up a subwoofer, including the REL, is to set the crossover frequency on the subwoofer to that frequency, then play music or random noise that is clustered around the frequency and adjust the level of the woofer until you can’t tell whether the subwoofer is playing or not. This means that at the crossover point the main speakers and the subs are dovetailing perfectly with respect to level. After that you can then do whatever tweaking you like to tweak the balance a bit more precisely or in a way that you find more pleasing. For myself, I found that pushing the crossover a bit higher than the theoretically optimal 35–40Hz brought an additional weight, heft, body, and warmth to the lower strings, an effect that was subtle but very much to my taste and very close to my idea of a natural and “realistic” tonal balance.

But now I’ve got a guilty confession to make. What really made the process a breeze was when Robert Greene brought over the DSPeaker Anti-Mode 2.0 DualCore (see his review in Issue 204). This device generates a sweep tone that is picked up by a (supplied) microphone placed at the listening position and presented as a frequency-response graph on the Anti-Mode’s LED display. In no time at all we could move the speaker around, adjust level and crossover, look at the results, and readjust until we had the flattest response at the listening position. I’m happy to say that I was able to get it in the ball park using Sumiko’s method, rather closer doing it by ear, and as good as it was going to get using the Anti-Mode. Important note: We were not using the DSP function of the Anti-Mode, only its measuring function. (In my own arrogant opinion, REL or Sumiko might want to market such a measuring device. Stripped of its DSP function, it seems to me it could be very reasonably priced and its usefulness is self-evident. I’d certainly buy one.)

Getting the proper dial-in was only part of the job. Because my room doesn’t have an empty corner behind the speakers, owing to built-in shelving and nearby doorways, the 528SE initially wound up in a part of the room that also serves as a traffic area. Despite its attractive finish, it looked unsightly there and rather stupid as well. So I decided to situate it in the listening area, up against the back of the sofa. This actually happens to be a really good solution to subwoofer placement, because if the crossover is low enough, directionality isn’t an issue (a 100Hz wavelength is over eleven feet, 50Hz over twenty-two). With an assist from the Anti-Mode (again for calibration only), we were able to get excellent measured results that translated into superb listening.

I had to settle for some compromise, which obtained in the first as well as the final placement of the REL. As a trade-off for a bit more fullness in the 70–100Hz range and real strength at the very bottom of the spectrum, there’s a mild, narrow trough around 50Hz. The listening area is a given in my room, so the only alternatives to eliminating this require moving the main speakers or the subwoofer. But the main speakers are very happy where they are, as am I, and no amount of repositioning the subwoofer to any place that wasn’t too awkward to live with flattened out the trough. There is only one way this can be fixed—outside of DSP or a parametric equalizer—and that is by using a second subwoofer. I’ve done this before and it works like a charm. You simply find a place for the second woofer that doesn’t result in a depression in that frequency range at the listening position. But if you opt for this solution, don’t be surprised if your woofers wind up being in very strange, counterintuitive parts of the room. Bass modes rarely accommodate our requirements for aesthetics and convenience. REG, who’s done a thorough and systematic study of this, informs me that most real acoustics experts agree that the best way to get a really smooth, flat bass response is by using several subwoofers distributed optimally around the room. This raises an interesting question: Is it better to buy two or more smaller subwoofers than a single big one? The answer would appear to be yes. And in addition to allowing a smoother, flatter bass response, none of the woofers would have to be working all that hard as there are so many of them. The reproduction would sound less effortful, the distortion lower, and the dynamic range if anything higher. Of course, how one’s domestic partners would feel about this arrangement is another matter entirely.

What about DSP or EQ? Always desirable for smoothing and flattening the response, especially when it comes to pulling down peaks or reducing broad plateaus, but risky when it comes to filling in valleys or troughs. For one thing, it requires pouring a lot more amplifier power into your speakers, thus raising the possibility of damage or distortion. For another, you may not be able to do it at all. If you have a serious null at your listening seat, you can’t EQ that out. Why? Think about it: If you’re faced with an absolute null, which is to say zero loudness, then no matter how much you multiply nothing by something, the result is still nothing.


I’ve devoted so much space to setup here because I believe the R-528SE is truly a great product that will perform at its best only with careful attention to placement and calibration. So that I don’t scare potential buyers away, I must in fairness add that unpacking and just getting it to work are easy as can be, and if all you want is lots of subterranean bass with low distortion, you’ll get it in short order. But this subwoofer is able to do something very special. It’s a kind of chameleon that can liken itself, as it were, to the main speakers, extending their bass response in such a way as to make it sound as if it’s organically and imperceptibly continuous with their sound, not a box that woofs along with it. But you’ll get there only with some work.

The 528SE also offers truly breathtaking bass reach, low distortion, and high resolution in a compact package that I’d have little hesitation calling standard-setting both at its price and at several multiples above its price. In truth, I doubt there’s even a handful of subwoofers out there for any price that would put paid to its performance.

Right now I’m winding up this review listening to Rachmaninoff’s Symphonic Dances in the Dallas Symphony recording by Eduardo Mata (far superior sonically to the more famous one by Donald Johanos). The warmth and richness of the whole lower range of the orchestra win me over completely, while the bass drum is genuinely—well, kick-ass. Relative to which, that buddy of mine told me not long ago that he had picked up a pair of Quad ESL-63s that he’s presently having restored. Does this mean that I have the last laugh? Not hardly— the day the R-528SE has to leave will be an unhappy day chez moi.


Type: Front-firing subwoofer with 12" active woofer and down-firing 12" passive adiator
Low frequency extension: 21Hz at -6dB (in-room)
Built-in amplifier: 500 watts, Class D
Dimensions: 17.5" x 15.5" x 17.5"
Weight: 58 lbs.
Price: $2799

Sumiko Audio (U.S. Importer)
(510) 843-4500

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