MP3PRO format discussion
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From: Torrance, CA
MP3PRO format discussion
I recently converted my entire MP3 collection to MP3PRO (http://www.mp3prozone.com/ )
Basically, my collection has been converted from 4.41GB to 1.83GB, and I cannot tell the difference in sound quality. In fact, MP3PRO has the ability to sound better than the normal Fraunhofer mp3 format, while still keeping its filesize improvement. For more info, check the above link.
Anyway, in a real world application (my s2000 with an Alpine 7995 head unit), IT WORKS, plain and simple. I now have 288 songs on a single CD!
and I cannot hear a difference in sound quality! I used to fit only120-130 songs on one CD.
I'm not sure the mp3pro format plays well on all mp3 capable head units, but it seems to work well on mine.... I find it odd that it works, since Winamp cannot even play the mp3pro files correctly without an additional plugin!
I'm using NeroMix to convert my mp3 files to mp3pro (same file extension, BTW). From what I've discovered, you also need to install Nero Burning ROM as well as the Nero mp3PRO plugin for everything to work correctly. I highly suggest giving this format a try.
Even if everything seems to work, I'm hesitant to delete my old MP3 files, for fear that I will encounter a situation where MP3PRO doesn't work correctly. So, has anyone else tried this format? What encoder are you using?
Basically, my collection has been converted from 4.41GB to 1.83GB, and I cannot tell the difference in sound quality. In fact, MP3PRO has the ability to sound better than the normal Fraunhofer mp3 format, while still keeping its filesize improvement. For more info, check the above link.
Anyway, in a real world application (my s2000 with an Alpine 7995 head unit), IT WORKS, plain and simple. I now have 288 songs on a single CD!
and I cannot hear a difference in sound quality! I used to fit only120-130 songs on one CD.I'm not sure the mp3pro format plays well on all mp3 capable head units, but it seems to work well on mine.... I find it odd that it works, since Winamp cannot even play the mp3pro files correctly without an additional plugin!
I'm using NeroMix to convert my mp3 files to mp3pro (same file extension, BTW). From what I've discovered, you also need to install Nero Burning ROM as well as the Nero mp3PRO plugin for everything to work correctly. I highly suggest giving this format a try.
Even if everything seems to work, I'm hesitant to delete my old MP3 files, for fear that I will encounter a situation where MP3PRO doesn't work correctly. So, has anyone else tried this format? What encoder are you using?
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From: Columbia, MD
Hmmm, interesting DJ...I'll have to check out the site and see what kind of technical info they list and see where they're making their improvements. Now that my thesis is finally finished (although not defended), I finally have the time to play with my MP3 player. I hope to support multiple formats...MP3, AAC, Ogg Vorbis, etc....but I'm going to start with MP3. This may be another format worth consideration for support.
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From: Columbia, MD
All right, I spent a few moments looking over what they have as far as technical info goes on their website (and there isn't much). Essentially, MP3PRO takes the standard MP3 bitstream and splits it up into two separate bitstreams...one stream contains a downsampled version of the original MP3 data, and the second stream contains the MP3PRO-proprietary information.
Here's the rub, DJ...when playing these files on a standard MP3 player (i.e., one that doesn't support the MP3PRO format), it only reads the downsampled MP3 data and ignores the MP3PRO data. While this is great for backwards compatibility, it means that the signal being recreated by your standard player is of inferior quality since it has been downsampled.
So, what does this mean? If your player supports MP3PRO, this is a good option at reducing filesizes for reasonably similar (notice that I did not say equivalent) quality audio. If your player does NOT support MP3PRO, you have degraded the quality of your audio just as if you had taken a standard MP3 file at a similar bitrate (and more than likely, even worse).
In a nutshell, if all you have is a standard MP3 player, this is a bad format to encode your files in. Be glad you saved all of the original MP3s...
Here's the rub, DJ...when playing these files on a standard MP3 player (i.e., one that doesn't support the MP3PRO format), it only reads the downsampled MP3 data and ignores the MP3PRO data. While this is great for backwards compatibility, it means that the signal being recreated by your standard player is of inferior quality since it has been downsampled.
So, what does this mean? If your player supports MP3PRO, this is a good option at reducing filesizes for reasonably similar (notice that I did not say equivalent) quality audio. If your player does NOT support MP3PRO, you have degraded the quality of your audio just as if you had taken a standard MP3 file at a similar bitrate (and more than likely, even worse).
In a nutshell, if all you have is a standard MP3 player, this is a bad format to encode your files in. Be glad you saved all of the original MP3s...
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From: Honolulu
Interesting. So for non-PC MP3 players, the sound won't be as great right? What about the variable encoding rate software from LAME? Does this work on car or portable MP3 players? I care more about the quality of sound than I do size.
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From: Columbia, MD
rstark: Not just non-PC players, but any players that don't support MP3PRO decoding...this could include non-PC AND PC decoders. Tell me more about this LAME, gimme a website, whatever, and I'll check it out, too.
DJ, you could be seeing two issues here...if it sounds like crap at 90k, it may be that WinAmp is having a very difficult time separating the two streams and therefore the MP3PRO stream is partially corrupting the true MP3 stream. If that's the case, then your Alpine is probably playing the original MP3 stream correctly and completely ignmoring the MP3PRO stream (as MP3PRO was designed to allow). I can almost always hear a 90kbs file and say "That sounds like crap", but since quality is subjective, I can't really make any more educated guesses without having more facts (i.e., actually hearing the music coming out of your Alpine unit).
As bitrates drop, you'll start to lose the high frequency stuff pretty fast. From what I can gather from their website, the original MP3 stream is bandlimited to 10kHz and the second stream takes care of the rest of the info (when split up like this, you can play some more tricks with the individual streams, which would be my guess as to what they did). If that's truly the case, you should hear all of that high frequency info drop out when playing an MP3PRO encoded file on a non-MP3PRO decoder. This may not be too much of an issue on certain types of music, especially heavy bass music, but I would be curious to hear what classical music (i.e., symphony) would sound like...probably would sound like crap.
My point about the loss of info is difficult to define in a short set of words. It depends heavily upon their new method of information coding, but it could end up as one (or more) of several issues popping up, including loss of part (or all) info above 10kHz, full frequency spectra but subsampled (loss of time resolution), and a few other more minor details.
Grrr, makes me wish I had my decoder finished so I could take a look at their streams...
DJ, you could be seeing two issues here...if it sounds like crap at 90k, it may be that WinAmp is having a very difficult time separating the two streams and therefore the MP3PRO stream is partially corrupting the true MP3 stream. If that's the case, then your Alpine is probably playing the original MP3 stream correctly and completely ignmoring the MP3PRO stream (as MP3PRO was designed to allow). I can almost always hear a 90kbs file and say "That sounds like crap", but since quality is subjective, I can't really make any more educated guesses without having more facts (i.e., actually hearing the music coming out of your Alpine unit).
As bitrates drop, you'll start to lose the high frequency stuff pretty fast. From what I can gather from their website, the original MP3 stream is bandlimited to 10kHz and the second stream takes care of the rest of the info (when split up like this, you can play some more tricks with the individual streams, which would be my guess as to what they did). If that's truly the case, you should hear all of that high frequency info drop out when playing an MP3PRO encoded file on a non-MP3PRO decoder. This may not be too much of an issue on certain types of music, especially heavy bass music, but I would be curious to hear what classical music (i.e., symphony) would sound like...probably would sound like crap.
My point about the loss of info is difficult to define in a short set of words. It depends heavily upon their new method of information coding, but it could end up as one (or more) of several issues popping up, including loss of part (or all) info above 10kHz, full frequency spectra but subsampled (loss of time resolution), and a few other more minor details.
Grrr, makes me wish I had my decoder finished so I could take a look at their streams...
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From: Columbus, OH
Here's the LAME homepage.
http://www.mp3dev.org/mp3/
I'm not sure if the Alpine HU's will play a VBR encoded mp3. I can give it a try tomorrow if I get a chance.
I have a 7897 in my Accord, but I haven't tried using any of my VBR stuff on it yet. I basically re-encoded the music I wanted to listen to in the car at 192k. With the stock speakers that I haven't replaced yet, I can't tell the difference between a 192k and 256 or 320k mp3 in the car.
I'll let you know what happens with the VBRs.
http://www.mp3dev.org/mp3/
I'm not sure if the Alpine HU's will play a VBR encoded mp3. I can give it a try tomorrow if I get a chance.
I have a 7897 in my Accord, but I haven't tried using any of my VBR stuff on it yet. I basically re-encoded the music I wanted to listen to in the car at 192k. With the stock speakers that I haven't replaced yet, I can't tell the difference between a 192k and 256 or 320k mp3 in the car.
I'll let you know what happens with the VBRs.
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From: Honolulu
Originally posted by StrangeDaze
Just quickly burnt some VBRs onto a CD and gave it a shot. They seemed to play just fine on my Alpine 7897. Not sure if this means they'll work okay on all Alpine mp3 HU's... YMMV.
Just quickly burnt some VBRs onto a CD and gave it a shot. They seemed to play just fine on my Alpine 7897. Not sure if this means they'll work okay on all Alpine mp3 HU's... YMMV.
It somewhat works on a Panasonic home MP3 player. I'm thinking of upgrading my headunit to a MP3 (preferrably Alpine) one, and hoped varible bit rate MP3's would work. I'll make sure to test one out before buying.