View Full Version : Vegas Audio Problems...?


Kevin Crockett
February 24th, 2008, 02:05 PM
I'm sure there's a perfectly reasonable and logical explanation to the problem I'm having so I'm doing what I should have done earlier (posting it here) instead of spending the better part of this morning pulling out my hair.

I'm using Vegas 5 and a have a nearly 30 minute audio that I want to render as a CD quality (128 kbps, 44,100 hz) mp3. The problem is when I use that setting it renders but I can not hear anything when I try to play it.

The same thing happens with the 96 Kbps,44,100 hz setting but I can hear the playback if I use the 80 Kbps,22,050 hz or 64 Kbps, 22,050 settngs.

Any ideas on what the problem could be?

Greg Boston
February 24th, 2008, 02:33 PM
I have read in that past, though it may not be the correct answer in this case, that your sound card may not support those combination of sample rate/bit depth.

Just a thought,

-gb-

Kevin Crockett
February 24th, 2008, 06:15 PM
Greg

That might be true but I can hear the audio from a "store" bought cd. Are all store bought cds mastered using the same 128 Kbps 44,100 hz settings or do they vary?

Seth Bloombaum
February 25th, 2008, 02:26 PM
"128Kbps, 44.1KHz" may indeed be called "cd-quality" by many MP3 encoders, but it is not the CD standard, it is an MP3 compression standard. "128" refers to a bitrate.

The actual CD-Audio standard is 16bit (wordlength) 44.1KHz (sample rate), uncompressed. And no, it doesn't vary.

Greg may be right - something with sound card support (there may be driver updates), or with the MP3 player software you're using (try other software, you probably have 2 or 3 programs that will handle it, eg. WM Player, QT, WM Classic, Vegas, Sound Forge, many DVD sw players, Winamp, etc.)

Jon Fairhurst
February 25th, 2008, 02:43 PM
The actual CD-Audio standard is 16bit (wordlength) 44.1KHz (sample rate), uncompressed. And no, it doesn't vary.
For the sake of completeness, add to the above "2 channels (stereo)."

All told, a CDs datarate is 16 x 44,100, x 2 = 1.4112 mbps, or (dividing by 8) 176.4 kB/s.

http://en.wikipedia.org/wiki/Red_Book_(audio_CD_standard)

http://en.wikipedia.org/wiki/CD-ROM

Seth Bloombaum
February 25th, 2008, 05:56 PM
Thanks for the clarification, Jon, quite so. Always good to have the complete info, wouldn't want someone to be misinformed.

To highlight against the compression of 128Kbps Kevin used, CD-standard is a datarate of ~1411Kbps (what Jon said...).

In other words, the 128K MP3 compression throws away about 90% of the data. Which is great if you're trying to fit a few hundred songs in a couple GB of storage on an MP3 player, or will distribute over the internet, but not so good for most other things.

Kevin, let us know how the troubleshooting goes.