05 July 2009

Cancelling My Emusic.com Account; Sound Geekery

I’ve been a big fan of emusic.com for years, but it’s time to let them go. Not because they recently raised prices (they also expanded their catalog), but because all they offer is shitty MP3s.

Raising prices is fine, and I’m really glad for them that they’ve managed to expand their catalog. That must have involved intense negotiations with the major label goats.

However, even high bit-rate MP3s are noticeably worse than CDs or WAVs — do a back-to-back listening test on decent home stereo gear, it’s pathetic — but emusic sells only 192Kbps (VBR) MP3s. Sorry, guys... CDs really were an improvement over cassette tapes.

A couple years ago I did an MP3 (192Kbps) vs. WAV listening test with some metal (Gojira’s “Ocean Planet”), and had a friend do the same experiment. I didn’t tell him what I heard, but he responded that he heard exactly what I did: the bass frequencies were “richer and fuller” on the WAV (ripped from CD). I also thought the stereo imaging suffered in the MP3. The end result was that the tricky interplay between the drums and the bass guitar was muted in the MP3 — I think the sound difference actually affected the musical content of the song. And that was metal; the problem is worse for more subtle music.

Emusic subscribers are asking about quality, too. They aren’t getting any answers.

Lossy compression is dead. It was a solution to a problem that no longer exists: poor bandwidth and expensive storage. In 2009, we get megabits per second to the home and a GB of storage is $0.10 or less.

Add to this the fact that quality control suffers (almost every audiobook I’ve downloaded form emusic has had at least one terrible error — the emusic commenters complain too) and parts of their catalog have disappeared (I can’t re-download some stuff I got before), and emusic is no longer looking like such a good deal. I’ll spend my $30 per month at Amoeba instead.

In fact, even “CD-quality” sound (44,100 16-bit samples per second) is really not good enough to capture all the sound a human can hear. Producer and musician T-Bone Burnett has started releasing albums on DVDs with 96,000 24-bit samples per second. I hope, although doubt, that it will take off.

According to my handy Computer Music Tutorial, the dynamic range (in decibels) is roughly 6 times the sample width, and to avoid aliasing (high frequencies mangled into lower frequencies) you need to sample at a rate at least twice as high as the highest pitch you’re trying to record. (See here for more nerd details.) Although the theoretical maximum of 16/44.1 recording is pretty damn good, and although the loudness war does more damage than the digitization process does, you never really get the theoretical maximum. Digital recording is done at 24/96 (or even better), and it’s only downsampled and truncated in the last stage to fit the CD format.

16/44.1 can sound very good indeed... but in 2009, that’s the minimum.

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