Turntable cover


If TT has attached cover which swings up, what position should it be in when playing? How does it affect the sound in either position? Or should I remove the cover altogether? If I do, how do I keep the TT free of dust?
TIA for your replies. 
gg987
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Test it. Play the same track with it closed, at its default open angle, and removed. Let us know what sounds best.
Hi,
all TT’s sound best with dust covers removed. Take it off when in listening session and refit it afterwards. Simple as that. My DPS does not even have hinges.