I have a file .m4a audio file of size 805 kb which I wanted to convert it to wav. My purpose is to (1) get highest quality .wav audio file and (2) get 320 kbps .mp3 audio file.
I used an online service (https://www.online-convert.com) to convert it. When I converted directly without optional settings, the file size increased to 11.6 mb and when I converted the same audio with optional settings like, changing bit resolution to 32 Bit and changing sampling rate to 96000 Hz, the file size jumped to 50.7 mb
There are only two optional settings in the web service
Bit resolution - no change, 8 bit, 16 bit, 24 bit, 32 bit
Sampling rate - no change, 1000 hz, 8000, 11025, 16000, 22050, 24000, 32000, 44100, 48000, 96000 hz
And one raido button for Normalize audio that can be checked and unchecked
Can someone explain why the file size increases and what settings I must keep to get the highest quality from the original 805 kb audio?
Thanks