I strongly believe that mastering is an art in itself & the creativity that takes place in this stage is of equal importance to mixing.
When sending a mix for mastering, please send 24bit .Wav or .Aiff files between 44.1 kHz & 96 kHz.
Also, please name two reference tracks that are available on Spotify. This will ensure your master lives up to your expectations & more !
If it is scheduled for release & you would like it encoded please send any encoding details via email.
You'll hear many Mastering Engineers give strict instructions on "headroom" or removing bus compression.
Light compression on the output is fine with me to proceed & master, but please do avoid sending heavily compressed/limited Pre-Masters as this will be detrimental to having your track mastered.