Music in the Round #38 Page 3

The AS-EQ1 software steps the user through the procedure, which includes choosing one or two subs, then balancing the sub-level settings with the main speakers. Remember that output RCA? Connect it to an unprocessed, un-bass-managed input, and the software will prompt you to balance sub and main with equal outputs at 75dB. That done, the AS-EQ1 will provide the familiar Audyssey test signals to each of the connected speakers. SVS recommends a minimum of eight microphone positions (with a maximum of 32 for very large rooms), and the subtleties of mike positioning are similar to those of other Audyssey-based products. It will then calculate sub distances and levels, which you must transfer to the main processor or AVR—the AS-EQ1 does EQ only, not bass management or adjustments of subwoofer distance or level. In this it mimics the functionality of Audyssey SEQ.

I first used the AS-EQ1 with my resident Paradigm Servo-15 subwoofer. Unsurprisingly, the results weren't much different from what I got with Audyssey SEQ. The good news is that the sound of the combination of AS-EQ1 and MultEQ was nearly indistinguishable from the SEQ's performance overall. If you have a MultEQ AVR or processor, you can now approach the performance of the SEQ for less money and without the additional A/D/A conversions, except for the subwoofer channel.

But that's not all. The other big deal about the AS-EQ1 is its ability to deal intelligently with two subs. I don't have a source for two sub signals, but as luck would have it, I recently took delivery of Paradigm's new Sub-15 subwoofer. I left the Servo-15 in place at the left of my listening couch, and positioned the new boy up front, between the right and center speakers. Running them both from the AS-EQ1 was nearly as simple as running only one: same procedure, one additional level-setting control, and lots more Audyssey bweeps. The software, knowing there were now two subs, tested them separately and together, because they now had to work together. Because my Integra DTC-9.8 provides only one subwoofer output, the AS-EQ1 gave me only one distance and one trim, but those worked better than fine.

The bass performance of the system was simply superb. Although there was nary a bit of chestiness in voices or cellos, the bass had a tightness and an extension that were awesome. Pipe organ finally sounded real, not merely big. That and sound effects could shake the room, giving the impression that every molecule of air in it was moving. Of course, I'd doubled the number of dedicated 15" woofers, but that wasn't the whole story.

The original Servo-15 measurements showed a smooth rolloff beginning just above 20Hz, but with considerable variations between 30 and 120Hz. Equalizing this subwoofer with the AS-EQ1 almost completely smoothed the bumpy response, but the frequency response wasn't extended because Audyssey recognizes the –3dB point as the limit for its corrections. When I added the second sub, placed in a decidedly asymmetrical position, the unequalized summed response of the two subs together was already smoother and extended below 15Hz before beginning to fade. The AS-EQ1 made the most of this, returning a ruler-flat response down to about 13Hz. No wonder my system's new bass performance was so revelatory.

I have no hesitation in recommending the SVSound AS-EQ1 subwoofer EQ. It's a superb solution for the multi-sub club, and may encourage others to join. The AS-EQ1 will also get the best out of a single sub. But there's a hidden pitfall: While the AS-EQ1 will do a dandy job with your sub(s), without excellent room acoustics and/or a compatible room-EQ system, much of its good work can be submerged by modal influences in the range between the bass-management crossover (typically 80Hz) and the Schroeder frequency (typically 200–250Hz). Of course, the same can be said of any standalone subwoofer equalizer, including the Velodyne SMS-1 and the AntiMode 8033, but neither of those can handle two subwoofers independently, or interact so cooperatively with an Audyssey MultEQ–equipped processor. Overall, the SVSound AS-EQ1 is the best subwoofer equalizer I've seen.

Meridian HD621 HDMI Audio Processor
It's about time. For the past two years, I and other owners of Meridian processors have sat on the sidelines, watching the passing parade as mass-market AVRs have appeared sporting HDMI inputs for Dolby TruHD, DTS HD, and SACD, while we've been forced to use fiddly and compromising arrangements with multiple analog cables. Meridian has not been alone in holding off but now Bob Stuart and company have come up with the HD621 HDMI Audio Processor ($2995), as unique a device as might have been expected from them.

First, the HD621 will work with any Meridian processor that can handle a Smartlink/MHR, including the G61R, G68, C61R, and the 861. Second, no hardware modifications are needed to add six HDMI inputs and switching. Third, the HD621 isolates high-definition video from the chassis of the main audio processor by splitting the HDMI input signal into separate audio and video feeds and sending them to separate outputs. Finally, Meridian has added a "special sauce" of its own.

The 19"-wide HD621 is 1U-rack unit high and has a single button on its front panel. One blue LED indicates standby status, and illumination of one of six others denotes which input is active, selected via the pushbutton. Although these are almost superfluous in normal operation, they do permit manual input selection. The rear panel sports one video HDMI output and six HDMI inputs, the latter numbered and labeled: H1 DVD, H2 TV, H3 Cable, H4 Sat, H5 VCR 1, and H6 Game. To their left are the RS-232 and Meridian Comms connectors (to integrate control with the main processor). To their right are, in order, an RJ45 jack for MMHR output (Meridian's new digital multichannel audio link), four RCA jacks for Smartlink/MHR output (Meridian's encrypted digital output with two channels on each jack, sorta like S/PDIF), and the power switch, fuse post, and AC inlet. I connected two HDMI sources to HDMI inputs 1 and 2 and connected three of the MHR outputs to my 861 surround processor's IE42 digital input board (I'm limited to 5.1 channels, but so is my music). I flipped the power switch, and guess what? It just worked. The feisty Oppo DV-980H upsampling universal player was now sending multichannel digital PCM directly to the 861, and all three components were making glorious music together.

Of course, there's more. After I'd added the Meridian Comms connection and spent a few minutes with the HD621's Configuration program, the 861 recognized the HD621 as a kindred spirit, letting me turn it on and off, select its inputs from the system remote control, and, to my great pleasure, display my assigned name of the source player in big lights on the 861's front panel. This is the antithesis of kludge.

The HD621 extracts the PCM audio from the HDMI input, FIFO-buffers the PCM, and up/downsamples it for output to the main processor. I chose the high output rate, which outputs 24-bit words at a sampling rate of 88.2 or 96kHz. I could also set it up to pass along native DTS and Dolby Digital unscathed to the superior decoding engine in the 861. TruHD and DTS HD, however, must be decoded to PCM in the player, as the HD621-861 can't. Same for SACD. Lip-sync delay is also available, but as I'm without a video display in this all-audio system, I didn't need it.

As simple as was the integration of the HD621 into my system, it's not easy to describe its performance. I had almost forgotten how natural and unprocessed the 861 can sound, despite its formidable internal complexity. I'd been using the Parasound P7 multichannel analog preamp with the NeptuneEQ (reviewed in my July column) for some weeks, and they offered clear and balanced sound. And without a direct comparison, it wasn't apparent that anything was missing. Removing the NeptuneEQ upset the interchannel and harmonic balances but injected a dose of transparency. Swapping out the Parasound for the Meridian combo let me bypass the players' DACs, resulting in even greater transparency, and restoring the other felicities, including of Meridian's subtle room EQ.

Recently, I extolled the virtues of my modified Oppo DV-980H, which allowed me to feed multichannel PCM data via three S/PDIF connections to the 861. Now, however, I'm using the HD621 for this connection. Switching directly between these options revealed that HDMI via the HD621 sounded more detailed and "open" than the 3xS/PDIF connection. The openness was apparent in the spaces between the instruments and voices in good multichannel recordings, such as James Levine and the Boston Symphony's new SACDs of Brahms' Ein deutsches Requiem (BSO Classics 0901) and Ravel's Daphnis et Chloé (BSO Classics 0801). These performances may not appeal to everyone, but the somewhat distant perspective framed by John Newton's engineering allows the entire soundstage of these huge works to be accommodated within the listener's room without cramping.

But here's the really great news about the Meridian HD621: Plain old CD sounded superb, even from a modest player like the Oppo DV-980H. Despite the many observations that jitter on HDMI can be an order of magnitude greater than that on S/PDIF, the Oppo sounded so much better upsampled via HDMI in the HD621 than direct via S/PDIF to the 861. This upsampling is accomplished by "apodizing" filters identical to those used in the Meridian 808.2/808i.2 Signature Reference player/preamp, which are similar, in principle, to those in the Ayre DAC that so impressed me at the 2009 Consumer Electronics Show. This "special sauce," plus the FIFO buffering, probably goes a long way toward reaching the theoretically ideal situation in which one's choice of digital transport has little or no influence on the sound. I wish I had an 808.2 on hand to test that theory.

Meridian owners can rejoice in the HD621. Sure, it's one more box, but it keeps video noise out of the main processor. Sure, it accepts only PCM audio, but most of today's Blu-ray players will decode hi-def audio. Sure, it costs $2995, but I didn't expect it to go for much less. So rejoice—the HD621 brings HD audio to Meridian systems, and it sounds superb with non-HD sources as well.

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COMMENTS
mdunjic's picture

Establishment of computer audio should be blamed ... iTunes doesn't play SACD format and it is the most used user interface for playing the music through the computer. Most people who switched to computer music libraries (I have all of my collection in WAV format stored on hard disk) are happy enough with old CD format.

That's why.

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