Posted by Jack on 11/27/07 07:48

I have been happy with WMA sound quality at 128 kbps (44 kHz CBR),
believing it to be generally cleaner than its MP3 equivalent. WMA built a
reputation as excelling at lower bitrates (i.e. 64 kbps) and was also said
to surpass MP3 at 128 kbps. To my ears, it did/does have a more crystalline
quality on a lot of music. Subjective? Maybe. I hadn't noticed any real
distortion on my good quality car stereo (main usage for WMA) until the
other day.

I was stunned to hear how bad WMA 128 kbps sounds on Neil Young's "Down By
The River." That track has repetitive dull cymbal/brush hits throughout and
it's not a pristine recording to begin with. Apparently the WMA (9.2)
encoder treats those hits as some sort of lo-res background noise. This may
be compounded by distorted guitar harmonics that chase along.

At certain points the hazy cymbals fade in and out with a breathing effect;
an artifact nonexistent in the original WAV. It's quite evident between
3:30 and 4:00 in this 9-minute song. Parts of the song have crisper highs
and those seem to be handled OK, but it's still a disappointment.

When you increase the WMA bitrate to 160 kbps, it seems to lose this
affliction, and at 192 kbps sounds close to the CD. But MP3 (tested with
LAME & FhG) handles that track noticeably better at 128 kbps. With a
thousand songs encoded at WMA 128 kbps, I'm rethinking formats. This slush
might show up elsewhere.

Could this be a fluke or has WMA been using tricks to sound better than it
really does? If anyone knows other "WMA torture tests," please post song
names.

Jack

[Back to original message]