Yes mastering with Ambient music is very different to other music. Please feel free to share your experience on this...
There was a warning to this topic which said "...this topic has not been posted in for at least 120 days...".
Still, I wanted to share my ideas not in a new thread but here
I listen to music and ambient music since 22 years, I played ambient from vinyls, Cd's and Files.
It always needed a correction in the Eq's. Therefor, I agree with the people here who say: Mastering ambient music is mostly about Eqing.
Personally, in my music productions (I make music since 2009) I prefer the natural sound of an instrument, effect gear, audio interface, audio mixing console and daw.
I dont use Eq's and compression anymore. I create the sound on the instrument as if I would master. All equipment on, and really, this is underestimated.
The equipment makes the sound. Most important is the audio mixing console and an external audio interface.
If you want to create professional ambient music, you need to hear differences, before you even think about compression.
I agree with the opionion of the people here in this thread. Ambient music needs headroom (especially music with deep ends).
To understand compression, just imagine consolidation, and your ears will guide you.
Some experiences with mixing/mastering:
A sub bass without (the right amount of) headroom, makes pressure in your ears.
A stereo-imager used on panning sounds can make them lost in the spectrum.
Eqing can change the tones/mood of the music.
Extreme stereo panning (left-right-rotation) makes pressure in your ears.