Studio acoustics.... and coving.

Elffin
Hi about to place bass traps in the corners of my room and have realised that coving stops the bass traps sitting tight in the corner.

Whats the best option? Ive read i souldnt cut the foam since it changes ghe size of the trap and therefore does not have the proper..

or do I place the trap as close to the coving as possible?

Foam, if that's what it is, is not the best material for a bass trap.  Usually it is wrapped fiberglass or mineral wool panels, the thicker the better.  Having a bass trap stand away from a wall is better than having it right up against the wall since the space also contributes.  So it's like you have a thicker bass trap.  Also, on an outside wall in the winter, it's not a great idea to have a lot of insulation on the inside of your vapour barrier (which is in the wall) since you then risk condensation.  The air space avoids this.
 
Are your bass traps corner shaped ?  If they're just thick panels there's no problem since the panel will be mostly away from the wall already, if the trap straddles the corner.  And the coving would play no role at all.