"Peaceful, Easy Feeling"
132 kbs average
132 kbs average
128 kbs
-br 128 -qual 9 -production
128 kbs
-h --nspsytune --athtype 2 --lowpass 16
128 kbs
Version 1.0 (Build 84) Jun 12 2001
Note: 64 kbit/s
Notes by ff123
6/13/01: Addec spectral view of MP3Pro at 64 kbit/s (not 128 kbit/s, like the others).
These are graphs of frequency vs. time. These graphs can sometimes provide useful information about what a codec is doing. For the sample used here, the Psytel, and especially the WMA graph look different from the others. During periods of relative quiet, the frequency cutoff is allowed to drop. Compare these with the graph of Lame mp3, for example, where the high frequency cutoff is relatively constant for the range of loudness encountered in this particular sample.
Depending on how loud the "quiet" portions really are, various codecs decide if they can lower the frequency cutoff during those times. If the quiet portions are loud enough to hear, then dropping the frequency cutoff may produce audible alterations in signals such as background noise and hiss. People with good high-frequency hearing are more likely than others to notice these alterations, since the changes are occurring at about 13 kHz and above. On the flip side, artifacts below 13 kHz can be significantly improved with the bits that are saved by throwing away quieter high-frequency content.
Perhaps this is why some people say that WMA 8 sounds good (like me, who is older and has lost some high-frequency ability), and others say that it sounds weird (like bAdDuDeX, who has the ears of a bat).
| Encoder | Spectral View, sample of
Eagles "Peaceful, Easy Feeling" |
| WMA 8 (8.0.0.0302) 132 kbs average |
|
| Ogg Vorbis beta 4 132 kbs average |
|
| Liquifier Pro 5 streaming 128 128 kbs |
|
| Psytel AAC version 1.0 April 19, 2001 -br 128 -qual 9 -production 128 kbs |
|
| Lame 3.88a10 (Mar 16, 2001) -h --nspsytune --athtype 2 --lowpass 16 128 kbs |
|
| RCA mp3PRO Audio Player Demo, Version 1.0 (Build 84) Jun 12 2001 Note: 64 kbit/s |
|