Placement of Dual Powered Subs with Tower Speakers

Erik wrote:  " Well, color me surprised this works as well as you have experienced!! It feels a little too much like relying on serendipity for me to have every thoguht to try it this way. :-) "  

I have nothing against measurements and modelling and use both extensively myself. But not everyone has access to such, so I have suggestions which do not require them.

Duke

My suggestion would be deliberately placing both subs with asymmetry in mind. For instance, one might be on the front wall near the left corner, and the other might be on the right wall near back corner, but a different distance from that corner than the first sub is from its corner. (You want to avoid running that second sub - the one furthest from the mains - up very high in frequency, because you don’t want it passing upper bass energy loud enough to betray its location when the music is playing.)

The general idea is that each sub interacts with the room differently and produces a significantly different in-room peak-and-dip pattern, and it is the SUM of the two dissimilar peak-and-dip patterns that matters. Nothing against the strategy Erik recommends, his may work better; either one will result in a worthwhile improvement.

If both subs have phase controls, there may be yet another strategy you might try.

Whatever placement strategy you use, imo the exact position of each sub is less critical than when you only have one sub.

Duke

@erik_squires asks a really good question:

"What exactly do you think the difference is, in setting up 2 speakers between what we are recommending?? , because I can’t see it. :)"

The difference is admittedly subtle. Just to recap, your suggestion:

"You want to place the first sub as ideal as you can, then place the second so it fills in the nodes left behind."

And mine:

"deliberately placing both subs with asymmetry in mind."

Both suggestions end up with asymmetry; but there is a minor difference in the starting points: Yours starts with optimizing for one sub and then adding the second, and mine starts with planning where they BOTH will start (which is far apart, and asymmetrical).

My partner Jim Romeyn (who manufactures the DEBRA system and is probably better at set-up than I am) recommends your approach, complete with ye olde "subwoofer crawl".

Duke

Erik asked: "OK, so how do you get to this asymetrical plan? Do you use a room simulation similar to REW’s?"

You could.

In practice the room’s layout usually imposes constraints, and from there one just applies the basic principle of maximizing spacing and asymmetry. Like I recently did a layout for someone who wanted to avoid wires crossing walkways, and one quadrant of the room was off limits. Those were the constraints, and from there it was pretty straightforward.

Duke