Most subwoofers are pretty similar, but not the Sumiko S.9. Well, it's like a few other subwoofers, but substantially different from most. For audiophiles, this is a good thing.
Sumiko's new subwoofer line is marketed as "by Sonus Faber," referring to the famed Italian high-end speaker maker, but I can't see any particular commonalities between the Sumiko products and Sonus Faber's speakers. The S.9 reviewed here packs a 10-inch, down-firing driver, a 10-inch front-firing passive radiator, and a 350-watt RMS Class AB amp. That's something of a rarity in an era when most subwoofers use Class D (digital) amps. At 15.9 inches high, it's not particularly large; and, at $999, it's not super-expensive--although it is pricier than roughly comparable factory-direct models from Hsu Research, SVS, and others.
There are also two smaller, sealed-box models: the $499 S.0, with a 6.5-inch driver and a 120-watt amp, and the $699 S.5, with an eight-inch driver and a 150-watt amp.
Anyone who knows subwoofers and/or high-end audio well can tell at a glance that the basic design of the Sumiko subwoofers was heavily influenced by REL subwoofers, one of the few subwoofer brands that diehard two-channel traditionalists endorse. Like REL subs, Sumiko subs are designed not so much to handle all the bass, as most subwoofers are, but to augment the bass response of existing speakers. The advantage is that this can make it easier to get a seamless blend between the subwoofer and the main speakers...and, as a result, a more music-friendly sound.
The most visible way in which these subs distinguish themselves is through their Neutrik speakON speaker-level input. Sumiko supplies a 10-meter-long cable with a speakON on one end and three bare wires on the other. You connect this cable to your amplifier's outputs, in parallel with your speaker cables. Thus, the subwoofer takes its signal straight from the amplifier. You set the subwoofer's crossover knob to the lowest frequency that your speakers are rated to handle (for example, maybe 40 or 50 Hz for a pair of small tower speakers).
The advantage of this setup is that the signal going to the speakers is unaffected. The input impedance of the subwoofer isn't specified, but it's likely to be at least 1,000 times greater than the input impedance of the speakers, so the amp and speaker won't "see" the subwoofer. The main speakers' signal doesn't pass through a subwoofer crossover or a digital signal processor. The speaker runs exactly as it would otherwise, and the sub just fills in with extra bottom end.
The disadvantage of this setup is that the main speakers get a full-range signal. With the crossovers built into AV surround processors and a few stereo preamps, deep bass is typically filtered out of the main speakers; this generally reduces bass distortion and lets the speakers play louder. It's rarely an issue with large tower speakers, but bookshelf speakers and smaller towers are likely to distort more if you run them full-range. Also, you or your dealer/installer will have to adjust the crossover by ear, through trial-and-error; with the subwoofer crossovers built into surround processors, little or no adjustment is usually required.
By the way, you might be wondering what the difference is between this setup and a subwoofer with a speaker-level input using standard speaker-cable binding posts. The only real difference is that the Sumiko subs (and the RELs, too) have an LFE input with a separate level knob. Thus, you can set up the subs as "bass augmenters" for stereo, then route all of the low-frequency-effects signal from Blu-ray discs and other 5.1-channel (or greater) sources to the sub only, so the really high-powered deep-bass stuff doesn't overdrive your main speakers. The LFE input is unaffected by the low-pass filter (crossover) setting on the subwoofer. It might be possible to do this with a conventional sub whose speaker-level and LFE inputs are active at the same time; you could set the LFE level using the surround processor's subwoofer-output level adjustment, provided it offers adequate adjustment range.
I started by plopping the S.9 into my listening room's "subwoofer sweet spot," which I've found is where most subs sound smoothest in my listening room. It's against the wall under my projection screen, between my center and front right speakers.
I used two different speaker systems with the S.9: my Revel Performa3 F206 tower speakers and some big Klipsch RP-280F towers (review to come). The electronics I used included a Classé Audio CA-2300 amp and CP-800 preamp/DAC, using a Toshiba laptop as a digital music file source. I also used my Music Hall Ikura turntable as a source, feeding an NAD PP-3 phono preamp. For surround, I used a Denon AVR-2809Ci receiver connected to an AudioControl Savoy multichannel amp.
For comparisons with other subwoofers, I used my Audio by Van Alstine AVA ABX switchbox, which permits precise level-matching and quick switching. When I set up the S.9 for some long-term listening, I used the AVA ABX as a simple remote-controlled on/off switch for the sub when it was wired to the amp. This let me easily and immediately gauge the quality of the sound with the S.9 in and out of the system.
I listened to the S.9 mostly using its intended setup, with the sub wired straight to the amp through the speakON connector, but I also tried using the LFE and line inputs.
Considering that using the speaker-level connection demands some tweaking of the crossover frequency and sub levels, and that you might want to change the level to suit different kinds of music, this thing could REALLY use a remote control. Just sayin'.
I'm going to start with a quick anecdote that illustrates what's different about this subwoofer. About the same time the Sumiko S.9 arrived, I also received a Klipsch R-115SW 15-inch subwoofer for review. Considering the R-115SW's size and its overbuilt 15-inch driver, I was eager to hear it. So I hooked up the Denon receiver and the Revel F206s, and I set the Denon's subwoofer crossover to the industry-standard 80 Hz. The R-115W delivered powerful, clean bottom end, but it wasn't blending perfectly with the Revels; the mid and upper bass lacked punch and definition. I swapped in my big Hsu Research VTF-15H; and, while the VTF-15H's extensive tuning capabilities let me get a better blend with the Revels, I wasn't quite satisfied. Then I tried substituting the S.9, and everything fell into place. The S.9 picked up right where the main speakers left off and sounded more like part of the system than like a separate subwoofer.
Sure, with more experimentation and fussing, I could have probably gotten a good blend from the R-115SW and a great blend from the VTF-15H, but the S.9 just dropped right into my system and sounded perfect with just a couple of twists of its controls. That's good because most people, and even some enthusiasts, wouldn't have the knowledge or patience to spend an hour or two fine-tuning their subwoofer.
The live version of Rush's "Anthem" from the recently released 200-gram pressing of All the World's a Stage illustrates the big plus for audiophiles: With minimal tweaking on my part, the S.9 blended beautifully with the F206s. Even though the S.9 was mostly filling in below 45 Hz, the improvement it made in the system's sound was obvious. "Anthem" starts with a guitar/bass unison run in 7/4 time played at an ultra-fast, Charlie Parker-type tempo. Without the S.9, the bass part nearly disappeared, and the guitar dominated. With the S.9, not only was the bass's contribution easy to hear, I gained new appreciation for the ultra-precise picking of the then-22-year-old bassist Geddy Lee.
"If you like bass players--as opposed to just bass--this might be the best $1,000 you could spend on a two-channel system," I wrote.
That thought was confirmed as I moved on to jazz bassist Sam Jones's album Something in Common. The opening tune, "Seven Minds," leads off with a dark, contemplative upright bass solo. Without the S.9, I could still hear all the definition and pluck in Jones's notes, but I got little sense of the body of the bass. With the S.9, I got all the body the bass should have--and a better sense of groove when the full band kicked in. Not one bit of the subtlety of Jones's playing was obscured; it just sounded appropriately full...and a LOT more satisfying, especially in the hard-grooving, extended bass solo toward the end of the tune. (Why Jones doesn't rank among the legendary jazz bassists is baffling to me.)
Basically, the S.9 made the F206s sound like the larger Revel F208s, although with smoother bass response because I was free to position the sub in the spot where it works best with my room acoustics. I found that, with music, the S.9 had enough muscle to do what I wanted it to do. Now, I didn't put on the latest Kanye West album and crank the system to the max, but I did put on the recording of the Saint-Säens "Organ Symphony" from the Boston Audio Society Test CD 1, which has deep pipe-organ tones reaching down to 16 Hz. Not surprisingly, the 10-inch S.9 couldn't handle the deepest tones the way a good 15-inch sub can, but it did reproduce them at a modest level without apparent distortion. When I clicked the AVA ABX box's remote to go back to the F206s on their own, the tones disappeared entirely.
Click over to Page Two for Measurements, The Downside, Comparison & Competition, and Conclusion...