Surround Processor Reviews

My initial reaction, unsurprisingly, was that the sound was brighter. Why was this unsurprising? Because Dirac, like Audyssey and most every other system I’ve tried, corrects the room-effect buildup of 50-to-120-Hz energy I well know to occur in my room, as it will in most others. So even casual listening reveals tighter bass octaves, along with the tonal-balance corollary of better-defined and seemingly more prominent midrange and treble.

However, there was certainly more going on than that. With Dirac engaged, reverberations sounded, not louder, but deeper, smoother, or shall I say, creamier, and perhaps even very slightly longer. Transients also were distinctive. The finger-snaps that open Diana Krall’s “My Love Is” clearly demonstrated both a more percussive snap and a richer, longer-seeming reverb tail. On the finger-snaps and on elements such as plucked acoustic guitar, harpsichord, and hi-hat ticks, transient leading-edges seemed highlighted—more prominent and snappy while not actually louder, as if richer in top-octave harmonic content, despite the fact that Dirac rolled off the top two octaves by a decibel or more.

Imaging, too, was different. Dirac shifted the Krall tune’s finger-snaps to dead center, from slightly left (where they appeared in non-Dirac playback), and made a perceptible sharpening of image location on a wide variety of recordings. For example, a rich but fairly diffuse rendering of Elgar’s Symphony No. 1 (an HDtracks download) enjoyed a noticeably tighter soundstage—which also seemed slightly deeper, and at the same time a bit narrower, or at any rate not wider in proportion.

One unexpected but subtly dramatic Dirac effect was one I simply stumbled across: On an ordinary Red Sox broadcast, the background crowd noise, which normally sounds more like a distant waterfall, became subtly more granular and lifelike, letting me more easily pick out the occasional distinct voice from the general ballpark buzz.

I spent an hour or more with my treasured copy of The Sheffield Drum Record (on CD), where Dirac clearly moved the kit into a more convincing and subtly more lively acoustic space—and this is a fairly tight studio recording. But here and throughout, my impression of enhanced brightness that wasn’t really brighter remained, and it grew even stronger when invoking Dirac over multichannel music via Dolby PLII/Music. Enough so that I went back to Dirac Live on the laptop and jiggered my target curves for all five channels, knocking everything down an additional 1.5 to 2.5 dB or so, from 1,500 Hz to 15 kilohertz. Repeating my listening, I heard, essentially, no change at all: The brighter, or perhaps clearer, or more sharply focused sound and the deeper or stronger ambience elements remained. Of course, what acted as a boon on better-quality recordings was not always advantageous on inferior ones like Bruce Springsteen’s Greetings from Asbury Park, N.J., where a clearer window onto bright ’n’ spitty wasn’t necessarily a good thing. Happily, defeating Dirac was never more than a key press away.

Dirac can operate upon discrete-multichannel modes like Dolby TrueHD and DTS-HD Master Audio (though not on direct DSD playback from SACDs, which the XMC-1 also can perform). Interestingly, I found much less obvious impact on movie soundtracks, except on prominent music cues. Dialogue and most ambience effects seemed relatively untouched. My speaker suite is quite neutral, especially through the vocal octaves, which may help to explain this: Little if any response correction is required (or seen, on the Dirac plots) in this range, and dialogue, being monaural to the center channel, may perhaps be less subject to correction.

There’s more to the XMC-1 than just Dirac, of course. Sound quality on straight (un-Dirac’d) movie or music playback was without blemish. (And I noted zero coloration on movie dialogue or TV announcers, centered or stereo, from Dirac engagement.)

The preamp accepts streaming audio up to 192/24 via a rear-panel USB port, so hi-res audio listening is a built-in option, though the XMC-1 has no music-server client functions of its own, working simply as a conventional asynchronous USB-DAC/preamp. (Direct DSD playback via USB is not supported—firmware update, anyone?)—but my DSD library played fine once converted to PCM by my Mac’s software player.

My other stereo hi-res tracks from my iMac streamed as well, though neither my software players’ “talkback” display nor the XMC-1’s own display ever showed a sampling rate greater than 48 kHz, despite playing files designated at 88.2, 96, or even 192 kHz. I initially took this to mean the Emotiva was decimating everything to 48 kHz (except native 44.1 stuff, which played at 44.1 kHz), and I could discover no setup option or control to manage this.

Emotiva’s in-house expert eventually became convinced that my long 16-foot USB cable was screwing up communication between my computer/player software combo and the C-Media CM6631A chip inside the XMC-1, which is said to be sensitive to timing that’s affected by cable length and the architecture of USB ports. In my case, it was surmised, the unsuccessful “rate-negotiation” suggested to my software that the XMC-1 was only a modest one-bedroom in the low-rent district instead of the high-end villa on the Riviera that it really is, so the player would send only the best quality it thought the pre/pro could handle. Emotiva recommends keeping USB cable length to two meters max, but the best I could do with my physical setup was swap in a 12-footer, which offered no improvement. Nor did switching the player software from Audirvana to any of several others I have resident. In any event, I’ve never had this issue before with any direct connection of my Mac (running OSX 10.9) to any DAC; the same cables running to a Micromega MyDac results in successful playback up to the maximum specified 96 kHz. Be warned.

This is as good a place as any to observe that, besides its automated Dirac corrective equalization, the Emotiva’s two additional memory registers each store an 11-band parametric arrangement for every individual channel, all 7.2 of them, with each band having independent adjustment of frequency, boost/cut, and Q (bandwidth/shape). This is a lot of processing firepower, enough for any of us to make things almost certainly worse by fiddling by ear and eye. Emotiva conceives these as mostly useful to the seriously techno audiophiles who wish to run an independent (non-Dirac) speaker/room-correction application, such as the popular Room EQ Wizard—or even perform measurements the old-fashioned way with SPL meter, pad, and pencil—and then enter the derived parameters manually. For those Luddites, the XMC-1 even incorporates built-in pink-noise and sine-wave signal generators.

Of more practical use, in my view, Emotiva endows the XMC-1 with unusually flexible tone controls, which can be applied globally or by individual input. Better still, Emotiva puts Center-Surround-Sub-Back channel-level trims—each with gloriously dedicated, hardware up/down key pairs—right on the XMC-1’s big remote, where they belong. Such rapture! These offer 0.5-dB adjustability and re-zero with each input change, a sensible, simple design expedient.

Emotiva claims the XMC-1’s front-panel headphone output is an amply powerful, high-quality circuit, and my listening seemed to confirm this. Thoughtfully, a completely independent set of channel-level and tone-control settings is recalled when you plug in the cans. And the XMC-1’s 12-volt-trigger-setup matrix even includes headphone presence (physically sensing a plug in the jack) as an option, enabling auto-powering-down of amps, or any other trigger-induced automation you can dream up. (These guys had their thinking caps on.) However, all multiband EQ processing, whether Dirac or manual, is defeated with ’phones connected. The mandate for the Dirac defeat is obvious, but likewise locking out the manual-EQ presets mystifies me; how cool would it be to have high-performing stereo-11-band PEQ to season your personal listening space to taste?

Lest I forget, the XMC-1 is a tuner-preamp, with onboard AM/FM reception and RDS display (but not HD Radio). And while it’s no dx-ing record-setter, the tuner doesn’t suck.

The remote that Emotiva supplies with the XMC-1 is a big, heavy, imposingly machined metal handset. It’s nicely laid out, with sensible key groupings and generous spacing. And there are lots of dedicated key pairs: In addition to the aforementioned and much-loved-by-me level trims, there are tuner seek, preset, and tune up/down pairs, as well as listening-mode, input, and (of course) volume, plus the usual four-way cursor grouping, and dedicated direct-access buttons for eight inputs.

The remote isn’t perfect, though (even if its magnetically secured rear battery cover is undeniably cool). I understand the high-end imperative for specialness, but I found the metal remote too heavy for comfortable single-handed ops, and there’s no lighting at all, a challenge in a home-theater environment (though the wide key spacing and varied shapes make by-feel operation possible, with time). And such custom, metal fabrication can’t come cheap; might not an off-the-shelf OEM remote (with backlighting) have shaved quite a few bucks off the MSRP?

One remote key, Loudness, demands special mention. This (or a setup option) transforms the pre/pro’s volume control from a simple attenuator to a true “loudness” control. Thus empowered, as it reduces volume from an (unspecified) unequalized reference point, it imposes equalization progressively as the setting declines, to compensate for human hearing’s deficiencies at softer-than-real-life amplitudes; this is an outstanding design concept. (Autobiographical note: We incorporated exactly this sort of control action, also optionally, in the Apt/Holman preamplifier, when I worked for that company about a zillion years ago.) Emotiva would get an A+ if they had based it upon more modern loudness studies (S. S. Stevens) rather than the familiar but outdated Fletcher-Munson curves they referenced. Still, it’s a back-to-the-future, honestly real-world-useful, feature. Bravo!

OK, I’m out of space and time—as might have said Paul Dirac, the English quantum physicist for whom the Swedes may have named their company. So here’s the executive summary: Emotiva’s XMC-1 is an intelligently engineered, fine-sounding A/V pre/pro with quite a few clever extras, almost all of them contributing genuine value in enhancing the audio or user experience. Its marquee feature, Dirac Live, seems to me to have real worth to those prepared to delve deeply and carefully enough to glean it. In all frankness, this issue’s short publication cycle has kept my own explorations fairly close to the surface so far, but Dirac definitely has my attention.

As does Emotiva, for the XMC-1 surround processor. It’s a high performer and an honest high- end value.