Does this technology exsist? (1 Viewer)

[chris bruce]

I have a HT room about 9x15x8 It is about 1180 cubic volume, I think. The HT room is setup with my in wall speakers and furniture and moving things around is not an option. The tv is directly in front of me with 2 svs pb-12plus/2's They are monster subs especially in that size room. Anyway on to the question. I am probally canceling each sub out since they are on both sides of the tv. But i will not move them because of looks. Is there some type of equipment out there that I can hook up so it stops the subs from canceling each other out?

 

[Robert_J]

The phase switch on the subs will rememdy that. But first you need to plot the each sub's individual response and then the combined response. If they are the same, then no cancellation. If there are extra hills and valley's in the response then there is cancellation.

How do you plot the response? An SPL meter, a free test tone generator and free Excel spreadsheet is the cheapest. Room EQ Wizard (REW), a calibrated mic and very nice sound card is the fastest and most accurate. It's not cheap.

-Robert

 

[brandonchenry]

Alright, the technology does exist! SVS is finally going to production on the long awaited Audyssey Sub-EQ!
http://www.svsound.com/CES2007/SVS_AudyessyRelease.pdf
I just got a hold of them to find out when they will start taking orders. They said CES will start pre orders, and the first of April is ETA on starting to ship them. They also said the cutsheet I linked above is soon to be updated with new art and plate updates.

 

[brandonchenry]

A simple fix for the short term is as follows:
Turn one sub off.
Set the other one to 75 db.
Turn sub back on, and the other off.
Set other to 75db.
Now when you play them both on with pink noise, they should register +6 db, or 81 db.
If it doesnt equal 81, start adjusting phase on ONE sub only.
Measure again (from the exact same spot!)
Once you have it dialed in to a combined 81, you will have fairly good wide bandwith phase coherance.