Music in the Round #44

When I started out on my multichannel mission in 2000, it was with an all-digital Meridian system that relied on lossy, compressed sources like the original Dolby Digital and DTS formats, or on synthesized surround based on Dolby Pro-Logic or Meridian's own TriField. With the appearance of first SACD and DVD-Audio and then Blu-ray, discrete lossless multichannel recordings became available, but there was no way to output those signals in digital form for interconnection to other components for playback or further manipulation. Most audiophiles, me included, already had analog preamps and power amps. It was only with the appearance of HDMI and the accompanying HDCP content protection that we could output those digital signals, and over a single cable to boot. Today, there are A/V receivers, some costing less than $500, and more than a handful of audiophile-oriented preamp-processors, that can accept such lossless high-resolution multichannel content as PCM, DSD, Dolby TruHD, and dtsHD Master Audio.

But not every audiophile has joined the home-theater stampede to HDMI. Some reject it outright for reasons of complexity or cost, or their own historical preference, philosophy, or inertia. After all, the signals do end up in the analog domain at some point before emerging from the speakers, and analog design and engineering have given us a wonderfully broad array of excellent electronics that many are reasonably loath to relinquish. I offer as strong evidence Oppo's BDP-83 Special Edition universal Blu-ray player, a stock BDP-83 to which Oppo adds an upgraded DAC and analog output stage. (I wrote about this in my March 2010 column.) Oppo recommends the BDP-83SE "to customers who primarily use the analog audio output" and maintains that, for those who use HDMI or the optical/coaxial digital audio output, "the standard BDP-83 is recommended." This clearly acknowledges a split in the specialist market that should be carefully examined.

Using a player's analog outputs: This seems a no-brainer. After all, it was how we all did it with the first SACD/DVD-A players—we had no choice. We could connect these players with six analog interconnects to our analog systems if we stacked three stereo preamps or invested in a six-channel preamp. This is still possible today, and some will argue that it remains the best way to go; it avoids the jitter that can be imposed by digital interconnections and, with some players, permits the direct conversion of SACD to analog without an intervening PCM conversion. I happily used this configuration in several systems over the years, but I have problems with it.

Three adjustments are fairly essential to achieving satisfaction with a multichannel music system: 1) interchannel level balance; 2) speakers equidistant from the listening position or compensatory time delays; and, in most cases, 3) bass management. While 1) and 3) can be accomplished in the analog domain, only the ability to adjust channel levels is relatively common in analog preamps, or in the "direct" (non-digitizing) modes of pre-pros and AVRs. Applying time delays to individual channels is not possible. Decent bass management is also rare in the analog domain.

But, you say, you can do all that in the player; and with most players these days, indeed you can. However, the flexibility and range of those adjustments vary widely. For example, Oppo's otherwise recommendable BDP-83 and BDP-83SE have all of these features, but their options are too restrictive for either of my systems. At the other end of the range, the Denon DVD-A1UDCI DVD player has options as useful and precise as those in any standalone processor. But so essential are these features to good audio performance that they should be of prime concern to anyone considering using a player's analog outputs.

Another, minor sticking point for those who wish to avoid intermediary conversion to PCM for SACD playback: all SACD players except Sony's SCD-XA9000ES do this processing only with derived PCM. Thus, you have to choose between your disdain for PCM and what I consider the three obligatory functions, unless you have five identical full-range speakers and a subwoofer, all positioned properly and equidistant from the listener. Even more significant is that multichannel analog outputs are disappearing from the rear panels of new disc players at an alarming rate, apparently to reduce manufacturing costs. Of Denon's two new universal players, the DBP-1610 ($499) has only stereo outputs (along with coax and HDMI), while the DBP-2010CI ($699) adds 7.1-channel analog outs. Eventually, analog outputs will disappear altogether.

Using the player's HDMI output: What does this offer over analog outputs? The argument is often made that you should choose to decode digital data in the player or the processor on the basis of which component's DACs are better. But this is moot; you can't generalize that one or the other type of component is always superior, and because the modern DACs in comparably priced players and processors are likely to differ little in direct comparison to the grosser effects of interchannel balance and arrival time.

There are some disadvantages to HDMI, but they're related to video issues that, in theory, should be of no concern to audiophiles. The first is that video functions and processing cost money, throw off a lot of heat in a crowded chassis, and can inject noise that affects audio performance. For good economic and marketing reasons, the vast majority of pre-pros and AVRs include video processing so that they can also appeal to the home-theater market. In addition, the HDCP handshake between HDMI source and receiver can result in dropouts as the disc continues to spin while the two components negotiate the connection.

And remember, even if you have no video source (such as with the HDMI-equipped Sony XA-5400ES, which plays only CD and SACD) or video display, HDMI cables still contain video clocks. Efforts to minimize these clocks' influence usually take the form of separating HDMI video from HDMI audio data, as has been done in Meridian's HD621 that I wrote about in September 2009, and in such Blu-ray players as the Marantz UD9004, Denon DVD-A1UDCI, and the upcoming Ayre Acoustics DX-5.

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