Home Theater Forum and Systems banner

1 - 9 of 9 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Here's my first crack at REW with the BFD. This is in a livingroom setup, dual subs, behind the couch at each end and equidistant from the center seat. I took measurements from my 3 main seating positions on the couch and averaged the results, then generated a PEQ recommendation which I tweaked a bit. Anything jump out as good/bad/ugly? Thanks in advance.

Average before (green) and after (purple) PEQ:
avg before and after custom bfd.jpg

Center seat waterfall before PEQ:
waterfall center before peq.jpg

Center seat waterfall after PEQ:
waterfall center after custom.jpg
 

·
Registered
Joined
·
275 Posts
I agree, it looks excellent. How have you treated your room?


Tim
:drive:
 

·
Registered
Joined
·
6 Posts
Discussion Starter #4
Thanks. I haven't done any treatments, just lucky. The room is 23'x16'x8', hardwood floor, an 8'x10' rug on the floor in front of the couch, bare painted walls (sheet rock?), glass french doors, and a 12'x4' window. And the "theater" is only in one end (16'x12') of the room. I thought things would come out much worse.:praying:

I have noticed a nice improvement in balance and detail after REW + BFD correction, both for music and movies. A very worthwhile purchase and effort!

Back to Master & Commander Blu-ray... :)
 

·
Registered
Joined
·
7 Posts
This is a measurement of only your subs, right? You couldn't do something about the minor dip at ~42 Hz with the BFD? Just asking for educational purposes as this would be my first foray into REW.
 

·
Registered
Joined
·
7 Posts
He could, but as you noted, its a minor dip, probably inaudible. It isn't necessary to achieve perfect flat-line response to improve the way it sounds.

Regards,
Wayne
Ok, and my other question was whether he was only measuring the subs and not one of the main speakers. If I measure with one of the main speakers, there shouldn't be an amplitude dip past the cross-over point, right? In other words, my FR should be relatively flat at the same amplitude all the way up to 200 Hz, right? Is that the right curve I should be aiming for?

And why measure only one of the main speakers with the sub and not both simultaneously?
 

·
Registered
Joined
·
6 Posts
Discussion Starter #8
Yes, my measurement was subs only, so it drops down along the blue track line. If I include a main channel in the reading, the chart is relatively flat to 200Hz.

2009-01-04 Subwoofer PEQ.jpg

Ok, and my other question was whether he was only measuring the subs and not one of the main speakers. If I measure with one of the main speakers, there shouldn't be an amplitude dip past the cross-over point, right? In other words, my FR should be relatively flat at the same amplitude all the way up to 200 Hz, right? Is that the right curve I should be aiming for?

And why measure only one of the main speakers with the sub and not both simultaneously?
 

·
Super Moderator
Joined
·
9,258 Posts
If I measure with one of the main speakers, there shouldn't be an amplitude dip past the cross-over point, right? In other words, my FR should be relatively flat at the same amplitude all the way up to 200 Hz, right
That’s theoretically true on paper, but when the sound is subjected to the room’s anomalies it may or not be readily apparent. The best way to check it, if you’re really worried about it, would be to measure the sub and main speaker separately, then together. At the crossover frequency, the SPL level should be higher with both together than separately.

And why measure only one of the main speakers with the sub and not both simultaneously?
Because if you don’t get the mic perfectly centered between the two speakers, there is a slight delay difference between the two speakers. That shows up in the measurement as comb filtering (i.e., sharp, ragged, up and down response). You’ll probably get plenty of that anyway just from room reflections, but no reason to aggravate it.

But it ultimately depends on the purpose of the reading. If you’re checking your speakers’ and sub’s frequency response, i.e., trying to identify problem areas where response is not linear, then the above approach is best. If you’re wanting to check the relative level of the mains compared to the sub, as in adjusting the blend between the mains and subs, then run both mains together.

Regards,
Wayne
 
1 - 9 of 9 Posts
Top