High definition audio has arrived

If you want to hear HD sound, you pretty much have to download HD tracks and play them on your computer.

technofile
Al Fasoldt's reviews and commentaries, continuously available online since 1983

High definition audio has arrived

Nov. 29, 2009

By Al Fasoldt
Copyright © 2009, Al Fasoldt
Copyright © 2009, The Post-Standard

   I've heard the future, and it sounds grand.
   I'm used to super-fidelity audio, having been a persnickety audiophile all my adult life. But nothing prepared me for the stunning sound I've been hearing from new HD audio recordings in the last few weeks.
   HD audio is an in-your-face, no-holds-barred way of playing back sound so good it can only be called high definition. It's so new -- so futuristic, even -- that it has already outstripped the capabilities of the "lowly" CD player. If you want to hear HD sound, you pretty much have to download HD tracks and play them on your computer -- and not just through your PC's tinny speakers, of course. You'll need to route the audio output of your computer into a high-quality sound system.
   When I did that, I was stunned at the sound of the dozen recordings I had downloaded (and a few more I had ordered on a data disk -- more about that shortly). Everything seemed more open and clear, especially in the treble range. Vocal sounds were especially pristine.
   Before I tell you where to get these recordings, I'd better explain what makes them different from ordinary CDs.
   Digital audio uses two separate processes to capture sound. The first one "samples" the sound many times a second. The faster the sampling rate, the more accurate the sample. CDs use a sampling rate of 44.1 kHz (44,100 times per second). The second function uses bits (discrete units of measurement) to gauge the sound. The more bits, the better the sound. CDs use 16 bits.
   The HD audio I auditioned was recorded using a higher sampling rate -- 96 KHz for most of the tracks, rather than 44.1 kHz -- and a bigger bit count, usually 24 bits instead of 16.
   To make huge download files smaller, many of these recordings are compressed as FLAC (free lossless audio codec) files. Get a free FLAC decoder called Switch from www.nch.com.au/switch.
   Someday, five or 10 years from now, this kind of HD audio will be commonplace. But it's decidedly rare now. Here is where you can sample these future delights:
      www.HDTracks.com (click the "96khz/24bit Store" link at the left). Album-length downloads cost $17.98. I especially liked David Chesky's "The Body Acoustic."
      www.itrax.com. You have many audio playback formats to choose from. "PCM 96/24" is the highest quality. Album-length downloads cost $21.99. "Guitar Noir" by Laurence Juber is my top pick here.
      www.gimell.com. All recordings from Gimell feature the Thallis Scholars, a singing group devoted to the sacred vocal music of the Renaissance. You have many quality levels to choose from. The best is labeled "FLAC 24bit 96kHz." I found many of Gimmel's recordings breathtaking, and my favorite is "English Madrigals (25th Anniversary Edition)."
      www.referencerecordings.com (click the "HRx" link at the left). HRx discs are data DVDs that contain WAV files (not FLACs) using 176.4 kHz/24 bit digital processing; they're shipped to you (no downloading needed) and cost $45 for album-length recordings. "Arnold Overtures" is my favorite. Note that other, non-HRX but genuine HD Reference Recordings albums are downloadable from the HDTracks site.