Well that depends on what you type of audio file you upload. Lets look at these possible conditions.
If you upload a .WAV files.
We will convert them to .AIFF, .FLAC, .MP3 and .OGG
Your fan will have the options to download: .WAV, .AIFF, .FLAC, .MP3, and .OGG
If you upload a .AIFF file.
We will convert them to .WAV, .FLAC, .MP3 and .OGG
Your fan will have the options to download: .WAV, .AIFF, .FLAC, .MP3, and .OGG
If you upload a .FLAC file.
We will convert them to .WAV, .AIFF, .MP3 and .OGG
Your fan will have the options to download: .WAV, .AIFF, .FLAC, .MP3, and .OGG
If you upload a .MP3 file.
We will convert them to .OGG
Your fan will have the options to download: .MP3 and .OGG
We can't convert .mp3 to any lossless format because we'd be downgrading it which would make no sense. If .MP3 is all you have then that's fine. Some .mp3 sound really good especially at 128 bit rate.
If you upload a .OGG file.
We will convert them to .MP3
Your fan will have the options to download: .MP3 and .OGG
We can't convert .OGG to any lossless format because we'd be downgrading it which would make no sense.
Most fans are familiar with MP3. They always will have an option to download an MP3 file.