Hi Larry. Using variable bit rates and joint stereo really apply to the ripping stage where you're taking tracks from an audio CD and converting to MP3. It doesn't really apply to burning them to CD.
You can re-encode MP3 that's at a higher bit rate and reduce it using variable bit rates. For example, if you had MP3's at a bit rate of 256kbps, you could reduce these to around 128kbps using variable bit rates. This would ensure that the quality never dropped below 128kbps but would give you more bits per second where the music needed it. This would result in the files being slightly larger than if encoded with a constant bit rate of 128kbps but you should hear some improvement in the quality. I've pasted some details below on the different bit rate methods that can be used that my be of interest. Bitrate Options: There are three types of bitrate options that you can specify for each the encoder (although some encoders may not allow any options). 1) Constant Bitrate (CBR) This is the default encoding mode, and also the most basic. In this mode, the bitrate will be the same throughout the whole file. So, a second of audio from one part of the file takes just as much disk space as a second from any other part of that file -- regardless of whether either part is silence, acoustically simple, or quite complex. This means that you are likely to hear distortion more in the complex parts than in the simple parts. The advantage of CBR formats is that even older players understand them, and that you can reliably predict the file size from the duration of the sound (or vice versa). 2) Average Bitrate (ABR) In this mode, you tell the encoder to aim for an average bitrate that you specify, skimping on the simpler parts of the music, and using higher bitrates for the parts of your music that are more complex. The result will be of higher quality than you'd get in a CBR encoded file of the same size. This mode is highly recommended over CBR. This encoding mode is similar to VBR. 3) Variable bitrate (VBR) In this mode, you say what level of quality you want in the output file, and the encoder compresses each second as best it can to get just that level of quality -- using less information to represent simpler parts of the song, and more information to represent the more complex parts. However, this mode relies heavily on the encoder's model of how you perceive quality, and could lead to a few "bad choices" in the encoding process. If possible, you may want to specify a minimum bitrate (e.g., 64 Kbps) to avoid those potential errors. Kevin ----- Original Message ----- From: "Larry N" <[EMAIL PROTECTED]> To: "PC audio discussion list. " <[EMAIL PROTECTED]> Sent: Thursday, April 29, 2004 5:18 PM Subject: Question concerning VBR and Joint Stereo on Standard CD Hi everyone. I have a data CD which consists of assorted MP3 files. My plan was to simply copy those files, paste them into folders and burn them onto standard audio CDs. A friend claims that for best results I should burn using a variable bit rate in joint stereo mode. It is my understanding that VBR and joint stereo apply to the encoding and editing of MP3's and MP3 CD's rather than to the process of burning MP3 files onto a standard CD. My question then is how do I take existing MP3's and apply VBR and joint stereo to a project involving such files? Additionally, if neither Nero nor Easy CD-DA extractor can perform the task, what screen reader compatible software would you suggest? Thanks in advance for any ideas. Larry _______________________________________________ PC-Audio List Help, Guidelines, Archives and more... http://www.pc-audio.org To unsubscribe from this list, send a blank email to: [EMAIL PROTECTED] _______________________________________________ PC-Audio List Help, Guidelines, Archives and more... http://www.pc-audio.org To unsubscribe from this list, send a blank email to: [EMAIL PROTECTED]
