Poll: least-worst-sounding 64 kbit/s format
Reply #2 – 2002-02-07 04:41:08
I’m dealing with each part of the track separately. I converted all four mp3 files to wav, and then chopped the wav files into 6 parts, labeling them "# codec" (e.g., 3 ogg). So I could more easily compare the codecs on each portion of the clip and compare. Here are my comments, by part of the song. Part 1 - acoustic guitar mpv32 has a fake, buzzy sound which seems to be added. The others all sound quite similar Part 2 - synth/techno mpv32 adds a lot of high pitched fuzz, which is quite annoying. Its replication otherwise seems pretty good. wma and mp3pro both make the drums come out with some metallic smearing, they’re a little different but I found them equally annoying ogg is perhaps a touch brighter than wma and mp3pro, but seems to have better clarity Part 3 - cymbals, drum, bass mpv32 - terrible echo effects, sounds like multiple cymbal strikes, when it’s clear from the others that there’s only one cymbal strike at a time ogg enhances/exaggerates the high-pitched range of the cymbals, so that they stand out more than in mp3pro and wma. mp3pro smears the cymbals a touch, while wma seems to make them sound more metallic than they should be; it gives them too much of a specific tone Part 4 - spanish guitar mpv32 the worst, again... fuzzy with lots of echo. The rest are pretty much equal, at least on the first half (quieter half) of this section, before the drums come in. wma maybe a touch duller than others, but that may be because mp3pro and ogg exaggerate the highs. After the drums come in, ogg really makes the drums sound louder by exaggerating the high snare sound. mp3pro and wma sound similar to each other, mp3pro probably a little better because wma adds more swishing. Part 5 - percussion mpv32 the worst, really exaggerates high frequency others are pretty close in quality Part 6 - voice (sitting...) mpv32 the worst, of course ogg is actually the worst of the remaining 3 - it makes the voice sound overly metallic and artificial - imagine a female Terminator singing mp3pro probably the best here, because wma is murkier Overall, mp3pro and wma usually sound very close to each other. To my ears, mp3pro sounds better than wma when there’s any noticeable difference between the two. ogg may be the most listenable for the majority of cases, but it does seem to change the sound from the sourcefile more than do wma and mp3pro. As Monty has said, listenability versus accuracy... but I think that this post-RC3 version of ogg may make too much of a trade-off where "listenability" is concerned. But it probably will sound more pleasing than mp3pro in most cases, even though mp3pro seems closer to the source wav file. But I think that RC4 shouldn’t do quite as much artificial brightness as this version does. I don’t have the original for reference; that would be nice... then I could tell how much ogg brightened some of the clips. The plus-V technology doesn’t seem to represent itself very well, at least when applied to mp3. But a lot of this could be due to the fact that the source wav had its sampling rate converted from 44.1 khz to 32 khz, and then back to 44.1 khz. This could have a large impact on echo and fuzz, I would guess. For reference, I converted the file hihat.wav, a 2-second clip that many of you are likely familiar with, to 32 khz wav and 22.5 khz wav, and then converted those back to 44.1 khz. The 22.5 handled it a lot better than the 32, which makes sense because it’s pretty much a 2:1 ratio. So perhaps, to be fair to the PlusV technology, you should downsample to 22.5 khz if you're going to downsample. edit: and from what is said on the website, plusV can supposedly be applied to ogg as well as mp3. Which might produce better quality at a given bitrate, because ogg is better than mp3 at the bitrate before application of PlusV technology.