Speaker placement

[Deedler]

Seating capacity is 120 with approx 150 max. One wall, mostly windows has curtains. Other walls have nothing. This is a semi private club with usually a 50/50 membership/guest ratio of customers of varying ages but mostly older. Not a Legion but similar. I have played this venue before for a Karaoke night with success. I had the speakers (2) out front just on either side of the stage. (more confusion I fear)
Now I will be expected to DJ therefore the dance floor will be used to a much greater extent. So, do I need more than 2 powered speakers etc. Should one be placed on one corner of the dance floor away from the stage? There is no other system in place.