Does iTunes compress audios synced to iPhone

[Trazy J Dozier]

I have a few mp3 320kbps audios I need to pass onto my iPhone, however, I need the format to be exactly the same and I don’t want any compressing to be done to the audios. I wanted to know if when I sync the mp3 audios to my iPhone, will iTunes compress the audio or change the format in any way.