The tradeoff, however, is that a mono 128Kbps file will sound "twice" as good as a 128Kbps stereo file.

Under the Custom tab when encoding to MP3 you will find options for stereo vs. mono.

"The tradeoff, however, is that a mono 128Kbps file will sound "twice" as good as a 128Kbps stereo file."

Is this true? Is there any difference in the sound? I know where the mono box is. If I check, it shortens the file, distorts and makes me sound like a chipmunk.

Has anyone else experienced this?

Thanks,

Thomas

I had the "chipmunk" problem with older encoders 4-5 years ago. It was a bug in the Frauenhoffer encoder. I can't remember if there was a workaround.

As for the 128 kbps, when you encode mono, you should cut the bitrate in half in order to get the same quality, i.e., 64 kbps mono = 128 kbps stereo (quality).

I just tried this with Vegas 5, and everything worked with the encoding set to 64 kbps.

Ah, I just remembered something. I think I the solution to your problem is to convert the mono files to stereo, and then encode as mono. I vaguely remember that the problem was that, when you start out with a mono file, the encoder still treats it as a stereo file, and puts one bit in the left channel and then next bit in the right channel. The bits end up "too close together," since in each channel every other bit has been removed, and it ends up playing at 2x speed.

See if first changing your files to stereo helps. Both channels will be identical, but the encoder should be "happier."

No such luck, John. It actually sounded worse, which I guess is irrelevant because the other one was unusable as well.

Is it affecting my sound quality taking a mono file and converting it into a stereo mp3?

Thanks for offering, though. I would have thought that more people would have ran into this problem.

Is it affecting my sound quality taking a mono file and converting it into a stereo mp3?

This isn't what I was suggesting you do. I probably wasn't clear. Here are the steps:

1. In an external program (e.g., SounForge), convert your existing audio file to a stereo WAV file. Use the same sampling rate that you plan to use in your final file (e.g., 44 kHz). Since you are starting with a mono file, this will create a two-channel file, with both channels having identical information.

2. Input this "stereo" file to the encoder, but encode as mono. Since you are only encoding one channel, you can encode at half the normal encoding, such as 64 kbps, 44,100 Hz. This will give you equivalent audio quality as what you get when you encode in stereo at 128 kbps, 44,100 Hz.

I pretty much make my living encoding to mp3 and a lot of that at 128Kb/sec, you should be able to get great results with mono at that bitrate.
First off, which version of Vegas are you using?
Secondly convert the files to mono and have a listen, most of the issues I've had have been with something wierd in the source material when it was converted to mono. You can convert to mono in Vegas, just R click the media and under channels select combine, you may need to drop the level 6dB to avoid clipping. Now have a good listen to that, is it pretty clean sounding?
MP3 mono at 128K is the same as 256K stereo quality wise so you should be able to get excellent results, in fact you should be doing OK at 64K for speech. Do understand though this depends on you telling the encoder to encode as mono, stereo or joint stereo.
Bob.

Bob,
He stated his Vegas version in the first post :-)

I absolutely agree that he should convert the signal to mono first, check it and THEN compress it to the desired format. (I always prefer wma to mp3, but that's probably beside the point.)
Tor