Magico Q-Sub 15 and Raidho D-5.1

Magico Q-Sub 15 and Raidho D-5.1

Over the last couple of years I’ve heard Magico’s humongous $22k Q-Sub 15 several times at shows, and while impressed by its (typical-for-Magico) rock-solid build-quality (a 350-pound, 20.75" x 21.5" x 26.5" sealed aluminum box with two 15-inch drivers, a 2000W amplifier, and DSP/XO circuitry inside), I wasn’t much impressed by its sound. In those trade-show demos the Q-Sub always seemed to stand out—as these things so very often do—like a sore, well, subwoofer. Oh, the Q-Sub had extremely deep bass, electrostatic-like resolution, and stake-in-the-heart slam, but the blend it made with various Magico speakers was anything but seamless. This has always been my problem with subs: What they give so plentifully with one hand in power, extension, and soundstage width, depth, and “floor” they take away with the other in discontinuity.

Indeed, I’d never met a subwoofer I truly liked until I came across JL Audio’s E-Sub and Gotham. Paired with the Magico M Pros the $15k Gothams, in particular, were magical. Which immediately raised the question of why this sub worked so well when the many many others I’d tried over the decades hadn’t. My conclusions was this: The Gothams blended so indivisibly with the M Pros because the subwoofers weren’t being called upon to do all that subwoofers are usually asked to do. Rather than making up for deficits (the absence of low-to-mid bass and/or suckout in the power range), the Gothams was merely augmenting what was already there in abundance—adding sub-20Hz extension, low bass sock, higher bottom-octave clarity, and better dispersion of the lowest frequencies to what was from the start a very linear, very full-range transducer (and it was doing this without any veiling of the signature Magico sound).

Since then it has become obvious to me that a subwoofer fares best where it works least. Crossing over the JL Audio Gothams at about 37Hz at 24dB/octave (high-pass only), carefully setting phase and gain by test measurement and by ear, and adjusting the subs’ physical location and orientation to achieve the most seamlessly neutral blend with the M Pros resulted in far and away the best stereo presentation I’ve ever gotten in my home. By pairing these subs with a speaker that limited the amount of work they had to do I got the sonics I’ve always dreamt of—a truly seamless, boxless, transparent, full-range sound that was faithful to sources (good, bad, or indifferent), faithful to the sound of the real thing (on records that sounded like the real thing), and yet still so packed with thrills and chills that every listening session was a goosebump-raising voyage of discovery.

Initially I doubted whether anything else out there could rival the JL Audio Gotham/M Pro combo in my digs; however, my opinion changed when I visited Magico’s dedicated listening room in Hayward, CA. There I got the chance to hear a pair of Q-Sub 15s paired with Magico’s fabulous new M3 loudspeakers, and discovered that, under these controlled circumstances, the 15s were capable of making the same kind of seamless blend with the M3s that I was getting from the JL Audio Gothams and the M Pros in my own listening room in Cincy.

When Magico offered me a pair of the Q-Sub 15s for review, I leapt at the chance. My plan was to duplicate the Q-Sub/M3 system in my third-floor listening room, and then cross-compare it with the JL Audio/M Pro setup in my second-floor room. But there was a problem: The M3s weren't going to be available until “some time after CES,” while the Q-Sub 15s were ready to ship. So, rather than waiting for months to try the Qs out, I changed my plans.

Upstairs I’m currently listening to Raidho’s D-5.1s. As you already know if you read my review in Issue 266, these Danish monoliths are greatly improved everywhere but the bass. The problem isn’t that the Raidhos have too little low end; on the contrary, they have too much of it precisely where “too much” is most annoying. Between 50Hz and 60Hz they generate a huge hump (a combination of port, enclosure, and room resonances) that can make certain notes on acoustic or electric bass sound grossly overblown and ill defined. While using port plugs ameliorates this situation, it also entails a slight loss of power-range color and energy that makes the speaker sound drier, less warmly balanced and gemütlich than it does without the plugs.

My thought was this: What if I rolled off the Raidhos where they lost control in the low end and rolled in the Q-Subs, which unlike the D-5.1s appeared to be exceptionally linear and low in distortion in the bass octaves, to cover that same ground. Of course, I couldn’t do this by means of the Q-Subs high-pass filter alone. I would need an outboard crossover with both high- and low-pass filtration.

Enter the JL Audio CR-1 outboard, analog subwoofer crossover, which I reported on many moons ago in TAS. This nifty little box works in conjunction with (or in place of) the filters built into JL’s (and Magico’s) subs, allowing one to dial in crossover frequencies, slopes, phase, and Q (the sharpness or smoothness of the roll-off) both high-pass and low-pass, with high precision.

With the CR-1, a pair of Q-Sub 15s, and considerable long-distance assistance from Magico’s chief technical officer, Yair Tammam, I proceeded to try the Raidho D-5.1 experiment. You can see the result in graphic form below:

Having done so many of them, I know that frequency response charts can be chameleonic and misleading, but this one (which is only 1/12th octave smoothed) actually comes close to reflecting the way the Raidho D-5.1/Magico Q-Sub 15 system sounds in my room. As you can see, though the bass still shelves up at 70Hz, it is very linear from there through 20Hz (actually through 15Hz!), and the huge peak at 50­–60Hz is gone.

After years of living with their foibles in the midbass, it is very nearly miraculous to hear the D-5.1 without its persistent port problem. Above the bass, it has always been a superb loudspeaker; the addition of the Q-Sub 15s made it a superb full-range loudspeaker system.

While the Q-Sub 15 is not as “user-friendly” as the JL Audio Gotham—there are no easy-to-read dials to twist or buttons to push on its enclosure, as all of its controls are software-based—once its software is mastered (and that will take a laptop, an intra-net, a microphone, some measurement software, and further instructions from your dealer or, in my case, Yair) you will find that the Q offers an abundance of fine adjustments and DSP options that put it in a class of its own when it comes to dialing-in subwoofer parameters and subwoofer sonics. Let’s face it: This is a Magico, so nothing has been left to chance. Short of coupling a sub to a dedicated state-of-the-art DSP unit—which is essentially what the Q-Sub 15 does—there really is no other way to contour a sub’s response to the peculiarities of your room with this kind of linearity. Of course, you do have to pay the penalty of digitizing your low bass (with the Raidho from about 57Hz down), but the plus side is so high that this seems like a very small price to pay for a speaker with 15Hz extension, the kind of in-room flat response you see in my frequency graph, and an enclosure and drivers that are so low in resonance they can generate 135dB SPLs at 20Hz with less than 1% THD.

I will have a great deal more to say about the Q-Sub 15 when the M3s arrive, but for the time being know that this is an exceptional subwoofer with all the neutrality, resolution, and transient speed that Magico Q Series speakers are famous for. (Along with the JL Audio Gotham, it is also the only subwoofer I’ve heard that is capable of three-dimensional bloom, nailing not just the pitch, timbre, duration, and intensity of acoustic bass notes but also the physical presence of those thick round strings.) Those of you with Raidho D-5.1s (or any other large full-range transducer) really ought to hear your speakers with the Q-Subs (and the CR-1). They will work wonders. With Magico’s own speakers, I’d imagine the benefits would be even higher (and the CR-1 unnecessary).