Yeah, that's what I was afraid of. Thanks, Jason, I'll try that and see how big the file is.

J--

Perfect Clarity Audio (*.pca), it's Sony's lossless compression format approximately 50% of wave. Any other compression format will be lossy. Ogg Vorbis is next in line but lossy.

MJ

Added later;
I should mention *.pca is only supported by Sony/SF apps. but I assumed your goal was to edit the *.mp3, save it at it's smallest lossless filesize and reuse it in another (Vegas) project which of course will involve an additional compression process (AC-3, Mpeg, etc.) for it's destination.

This is similar to photo editing. The rule there is to scan and edit in TIFF (or BMP) which is lossless. You can save as many times as you like, go back later and edit some more, and then save again. No loss. When you are finished and ready to archive, then save it as JPEG.

This is also similar to video editing. Do all your edits in DV AVI, which with Sony's amazing DV codec lets you create many, many generations without any noticeable loss. Or, if you are really a neat freak, save all your edits as uncompressed. Then, when you are ready to deliver, do the MPEG-2 compression for DVD.

In your case, I would recommend that you just save it as WAV until you have to finish the project and deliver it (I presume) in MP3 format. Obviously, you can encode at a higher rate in order to preserve as much quality as possible from the original files.

MJ, I was just going to ask about that... My apologies to all. No, it's not for a Vegas project... just using Vegas to edit the audio. I'm recording an Internet talk show (I have permission) and they broadcast live in MP3. I was just hoping to avoid too much loss in quality after removing the commercials.

Tried MP3 at 320 Kbps, it sounds no worse than the original. Forty-three minutes comes in at 100,000KB per program. I can get 6 shows onto a single CD that way.

Thanks for your help.

J--

How long is the show? I am resoring some radio shows from the 40's-50;s right now for someone & I save/edit them in mono. You could convert the radio show to mono, double the bitrate, then it would all be good. :)

Tuck, I tried rendering it in mono and it came out the same size as the stereo file! Surprised me.

Each show is 43 minutes.

J--

... you can encode at a higher rate in order to preserve as much quality as possible from the original files.

Thanks, John, I was hoping that would be the case.

J--

From what I know of mp3 encoding it will come out the same size, the question is how much of the bit budget is used up encoding unneeded data. I've just done a huge number of encodes that only have a few second of music in stereo at the start of each program, rest is mono. By using Joint Stereo the encoder only encodes the difference data on the stereo sections leaving more bandwidth available when its encoding the mono.
The only way to get the file size to vary is using VBR but there seems to be a few issues going down that path.

For mono, cut the bitrate in half in order to get the same quality. This will also cut the size in half. You can experiment on a short file, encoding first in stereo at 128 kbs, then convert to mono and render in mono at 64 kbs. The audio should sound the same (other than mono/stereo, of course).

IIRC, mono= 1/2 stereo is only true for true stereo files. Most lower bitrate MP3s are joint stereo, which is a bit more efficient, because there is usually a lot of redundant data between the channels of a stereo file. So, you can get similar quality in joint stereo to a mono file for less than twice the bitrate.

I think there are MP3 trimmer/editors that can do cuts only on frames and give pros/cons similar to MPEG video editors like this. Less editing accuracy, but no re-encoding of files. If I were editing MP3 sources, I'd look into this.

Thanks, Jesse. I found MP3 Trimmer is just what you were talking about. At only $5, it's appears to be a deal that is hard to beat.

J--