why 320 kbps mp3 have less vol compare to 128 kbps files?

[sumeshkri]

i have some mp3 files in 320 kbps. But a few of them have low vol compared to 128 kbps mp3 files. when i play it on computer a 320 kbps file need ,say 8 point of volume whereas, an mp3 of 128 kbps, play in that level very high.why this ? what to do to increase the volume? will the process distort the music in any way? thanks

[Baldrick]

Try mp3gain.

[guns1inger]

It has nothing at all to do with the bitrate, and everything to do with how they were converted in the first place. Obviously they weren't all converted at the same volume levels - a common issue for people who download their music through p2p and other non-commercial places.

[stewart2000]

wouldnt something like audio grabber be able to normalize them? so each had the same volume level

[guns1inger]

Possibly, but MP3Gain can normalise a whole folder full of MP3 files, does it in a smart and mathematical manner, and does so without re-encoding the files.