Hi,
I have been having the same issue with exported mixes, but also when listening to reference tracks. The imported reference tracks sound like they have an obvious reduction in sound quality, just like my exported mixes, when compared to other DAWS. Unfortunately I haven't found an answer to this, and 99% of the time if you ask questions about Studio One's sound quality, you will get the same idiotic diatribes about "all DAWs sound the same." All DAWs are SUPPOSED to sound the same, but that doesn't mean that they do not have errors, bugs, and general design flaws. Just look at FL Studio, which is supposed to be "non-intuitive" , and see the sheer amount of options in the export menu compared to Studio One!
A couple of hypotheses I can offer, however, are that Studio One 'squashes' some of the stereo tracks to mono during export, or the god-awful automatic routing feature actually sends a stereo signal back to a mono plugin, which 'squashes' the sound, before being sent to a main bus/mix bus/master bus, and it therefore affects the main output and the resultant export. I also have a suspicion that Studio One keeps routing in place after a bus has been dissolved, messing up the way the entire mix is mapped out in the console with no way to remedy it. This may be why I have good sounding mixes (still less sound quality when compared to other DAWS though) if they were completed rather quickly, or with fewer alterations.
If they do their job and see this post, the d-bags at Presonus will just blame your "hardware", or simply attack your supposed "skill level." My best advice is to set up a scientific experiment using your own mixes in multiple DAWs, as well as reference tracks in multiple DAWs, and export them with the same settings through the same system. Record your results. This would make a great topic for a Youtube video.
Best of luck to you and feel free to reach out:
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