Subwoofer Placement and Panning

From: Luis

Dear Bob,

I have two quick questions for you. One is regarding the subwoofer placement. I am using Dynaudio Bm5 as nearfields and two BM9s subwoofers. My nearfield are located on stands on each side of the console very close to me but I have no room for the subs. If I put them (the subs) all the way in each corner of the room they will be about one meter away and behind from the nearfields would this be a problem as far as phase is concern?. I usually see subs in line with the satelites or even a little bit in front of them but never behind and away from them. What is your opinion?

Yes, when subs are behind the mains it’s not possible to get the phase perfect and it’s a compromise because you can add delay but you can’t take it away! When the subs are behind the mains you have to delay the mains and it’s a tricky proposition. Phase is always a concern with
subwoofer placement. Generally you should do an alignment with a crossover that has a phase adjustment as well as the low pass and other adjustments. Nearfields and objects in between the speakers and the listener are always a problem. You should try to use a tool such as Fuzzmeasure or Spectrafoo to do the alignment properly. Expect to take several days to get it as good as possible. You need to take the effect of the room acoustics and listener placement into account when placing the subs as well.

The second question is usually I have the bass pan to the center in my mixes, what would happen if I copy the track to a new track and then pan one all they way to the left and the other all the way to the right, will the sound be perceived different in any way?

There’s no technical difference between panning a mono bass to the middle or copying to a new track EXCEPT that the levels will be INITIALLY 3 to 6 dB lower when you pan a single track to the middle. But it’s easy to make up for that as you are mixing by ear, so you just raise the fader.
Hope this helps,

Bob