tatjna
Disclaimer: I'm no kind of geek and quite new to both VDJ and understanding sound quality. I'm happy to do my own research but need some help to know where to look.
OK, the question. All of my music is in mp3 format. Some is downloaded and some ripped from CDs. I've noticed some of the downloaded files say in the hover-over file info that they have bitrates up to 656kbps - yet when played through VDJ the file info says 128kbps. At this point I'm not experienced enough to be able to really spot sound quality differences, but I'm aware that 128 isn't considered that great, so I'd be disappointed to find that these files are actually 128 and too crappy to play. I've also done a bit of research and found the highest mp3 bitrate mentioned on the internet is 320kbps, which makes me suspicious of the claim of 656..
I don't know how to find out whether they are CBR or VBR files.
Anyway, I'd like to know why the variation in bitrate reading - in Media Player they show up the same as in the hover-over info, but it changes as soon as I use VDJ. Another thing about these files - they all came in either a .zip or .rar format. The .zip ones even claimed on the site to have this extremely high bit rate (possibly more fool me for believing it without research). But I'm wondering if the decompression of the files may have something to do with the weird bitrate reading change. I've kept the compressed folders in case there's a way of decompressing them that fixes this. Files ripped from CDs keep a constant bitrate no matter where I play them.
Example tracks:
12:11 minutes, 656kbps, 22.6MB (downloaded as .zip, plays in VDJ as 128kbps)
07:13 minutes, 256kbps, 13.2MB (ripped from CD, plays in VDJ as 256kbps)
Any advice, pointers to places where I can learn more, or even derisive laughter followed by 'here's how you fix it' would be greatly appreciated.
OK, the question. All of my music is in mp3 format. Some is downloaded and some ripped from CDs. I've noticed some of the downloaded files say in the hover-over file info that they have bitrates up to 656kbps - yet when played through VDJ the file info says 128kbps. At this point I'm not experienced enough to be able to really spot sound quality differences, but I'm aware that 128 isn't considered that great, so I'd be disappointed to find that these files are actually 128 and too crappy to play. I've also done a bit of research and found the highest mp3 bitrate mentioned on the internet is 320kbps, which makes me suspicious of the claim of 656..
I don't know how to find out whether they are CBR or VBR files.
Anyway, I'd like to know why the variation in bitrate reading - in Media Player they show up the same as in the hover-over info, but it changes as soon as I use VDJ. Another thing about these files - they all came in either a .zip or .rar format. The .zip ones even claimed on the site to have this extremely high bit rate (possibly more fool me for believing it without research). But I'm wondering if the decompression of the files may have something to do with the weird bitrate reading change. I've kept the compressed folders in case there's a way of decompressing them that fixes this. Files ripped from CDs keep a constant bitrate no matter where I play them.
Example tracks:
12:11 minutes, 656kbps, 22.6MB (downloaded as .zip, plays in VDJ as 128kbps)
07:13 minutes, 256kbps, 13.2MB (ripped from CD, plays in VDJ as 256kbps)
Any advice, pointers to places where I can learn more, or even derisive laughter followed by 'here's how you fix it' would be greatly appreciated.
Posté Thu 15 Oct 09 @ 3:25 am
Andrew87
320kbps is the maximum bitrate for mp3. Virtual DJ cannot read bitrate properly for VBR tracks, neither can Windows Media Player / Explorer in XP. You can get a rough idea of what bitrate your mp3 is from it's filesize.
12m 11s is 731s. 22.6MB is 185,139.2Kb (note the lowercase b, indicating a bit not a byte). The filesize divided by the duration gives an approximate bitrate of 253kbps - so near enough 256kbps. If you wish to get a more accurate idea of the bitrate of your files, you may install MediaInfo, it's free and integrates with Windows Explorer.
CBR means constant bitrate and VBR means variable bitrate. As the name suggests, CBR keeps the same bitrate throughout a track whereas VBR does not - therefore CBR always requires the same amount of space even if compressing a simple sample. VBR keeps constant quality as it uses as many bits as the encoder thinks it needs based on the complexity of the sample. A 320kbps CBR mp3 is the maximum quality you can get from mp3. However, anything which is VBR 192kbps (or 256kbps CBR) is generally considered good.
12m 11s is 731s. 22.6MB is 185,139.2Kb (note the lowercase b, indicating a bit not a byte). The filesize divided by the duration gives an approximate bitrate of 253kbps - so near enough 256kbps. If you wish to get a more accurate idea of the bitrate of your files, you may install MediaInfo, it's free and integrates with Windows Explorer.
CBR means constant bitrate and VBR means variable bitrate. As the name suggests, CBR keeps the same bitrate throughout a track whereas VBR does not - therefore CBR always requires the same amount of space even if compressing a simple sample. VBR keeps constant quality as it uses as many bits as the encoder thinks it needs based on the complexity of the sample. A 320kbps CBR mp3 is the maximum quality you can get from mp3. However, anything which is VBR 192kbps (or 256kbps CBR) is generally considered good.
Posté Thu 15 Oct 09 @ 4:49 am
tatjna
Thank you! You know, I never even thought of just doing the maths. Doh!
Posté Thu 15 Oct 09 @ 1:49 pm