You can upload any tracks with a bitrate of 128kbps or less. You might have tracks with a bitrate of 32kbps, 64kbps, 96kbps, or 128kbps. It is recommended to encode all your tracks at the same bitrate, 128kbps, but this is not a requirement as long as the bitrates are not higher.
Our system will transcode the files to deliver a constant stream to listeners and that will help to slightly normalize the bitrate. Higher bitrates might be perceived as marginally louder, but not significantly so.
Audio normalization is the application of a constant amount of gain to an audio recording to bring the average or peak amplitude to a target level. There are programs available that can normalize your tracks, however, Live365 does not currently apply any volume normalization.