HD Audio, the Second Go-Round

September 28, 2006

Dolby TrueHDA funny thing happened about six years ago, two audio formats were introduced that offered superior sound to the compact disc; what’s funny about this you ask? by and large no one cared. But that’s not to say that all of us ignored SACD and DVD-A, however if anyone was looking for an excuse the limited titles available sure made it easy.

My indoctrination into A/V (like many others) was firmly based in the audio world; stereo, hi-fi, 2-channel or whatever you want to call it, was already a passion of mine long before the term home theater was commonplace in the American lexicon. Early on I found a couple of truths that have stuck with me ever since, 16-bit PCM at 44.1 kHz isn’t the end all of audio reproduction (with rare exception) and many manufacturers are just fine with that.

To this day I vividly remember hearing a turntable annihilate several of the crème de la crème CD players of the time; analog is continuous in both time and amplitude whereas digital audio is comprised of bits of data that must be reassembled and converted back into analog before we can enjoy it. This semblance of analog versus the real McCoy is by and large where many of digital audios problems arose.

As time marched on, digital to analog converters improved (drastically in some cases) and the inevitable tweaking of the compact disc format ensued. But it wasn’t until the advent of SACD and DVD-A that manufacturers addressed the real reason so many of those early CD players and titles lagged behind their analog counterparts, the bit-rate the audio was encoded at.

Simply put, in most cases more bits are better than less. As I mentioned above CD’s used 16-bit PCM audio at 44.1 kHz whereas DVD-A (in many cases) went as high as 24-bit/192 kHz. The easiest comparison is HDTV versus standard definition, by now most of us have seen what 720p/1080i looks like compared to 480i and the same basic principle follows through for high resolution audio, the more data from source that can be displayed/heard, the better.

Enter the iPod: Shortly after SACD and DVD-A’s introduction another product was introduced. Apple’s iPod promised thousands of songs on a tiny, handheld device that could be taken anywhere. Unfortunately (or fortunately depending on how you look at it) limited hard drive space dictated the compressed audio format Du Jour had to be used to pull off this feat.

Without getting into a huge diatribe against MP3’s, I’ll just say that Apple did what was necessary to bring their vision to market, but this has little to do with the pursuit of the highest possible reproduction of sound quality. Net result portability trumps performance, at least in this case. But as anyone who’s ever tried to pack their 42” plasma into a backpack knows, home theater is an entirely different market.

I’ve heard it argued that the majority of consumers can’t hear the difference between MP3 and CD, while this may indeed be true, especially if your listening to both through ear-bud’s, I’ll bet a good chunk of those same consumers could hear the difference between MP3 and DVD-A on a real multi-channel audio system. But to be honest this is neither here nor there because those of us who are able to appreciate the difference, will likely get another shot at high resolution audio.

One of the reasons I’m looking forward to the new high definition optical disc formats (one to a lesser degree for obvious reasons) is their potential to put hundreds of thousands of Dolby TrueHD capable devices into the homes of consumers, and possibly even spark a high resolution audio comeback.

The core technology of Dolby TrueHD is MLP Lossless which was used in DVD-A, but TrueHD adds the ability to deliver more flexible channel configurations with higher data rates. So fear not high resolution audio fans the HD format wars may be troublesome from an early adopter standpoint, but it may put more hi-res audio (capable) devices into homes than SACD and DVD-A proponents could have ever imagined.



Posted by Bryan Greenway | | Filed Under Blu-ray, HD-DVD


Comments

  • B.Greenway

    Hoyt, not “mandatory” in BD but that’s not to say it won’t be included in middle to upper tier players. On the TrueHD/PCM thing, I’m kind of torn on this, we can do PCM right now, but I kind of like the idea of de-coding in the receiver as they typically have better decoders.

  • B.Greenway

    Hoyt, not “mandatory” in BD but that’s not to say it won’t be included in middle to upper tier players. On the TrueHD/PCM thing, I’m kind of torn on this, we can do PCM right now, but I kind of like the idea of de-coding in the receiver as they typically have better decoders.

  • Hoyty

    I know the HD-DVD spec requires Dolby TrueHD support, but does Blu-Ray in its spec? Also do you think it will take until we have capable AVR for TrueHD to take off or will PCM mutli-channel be sufficient?

  • Hoyty

    I know the HD-DVD spec requires Dolby TrueHD support, but does Blu-Ray in its spec? Also do you think it will take until we have capable AVR for TrueHD to take off or will PCM mutli-channel be sufficient?