This weekend was a whole lot of fun. Friends came over on Friday night to have dinner and a movie but we wound up just tossing the kids down to the theatre with "Despicable Me" so the grownups could gossip and drink.
Nickshitachi drove up and brought all of his fancy analysis gear. We spent long hours on Saturday night measuring, listening, and tweaking settings to dial in the subwoofers and LCR array.
In case you missed it I was having a lot of trouble with my center channel... it sounded terrible. I replaced it with a full-range speaker that's identical to the left and right. I did this at the cost of going from 7.1 to 5.1 but I'll live.
Here are the before and after measurements that we did.
The room started out with a rather uneven response in the low frequency (as expected). You can see the room modes fairly clearly especially down there around 30Hz. You can also see the steep 20Hz rolloff that I installed due to the poor performance of these subwoofers below that frequency.
(Blue is the post-adjustment; purple is the pre-adjustment)
First we tweaked the "distance" parameter in the Meridian processor for the subwoofer channel to find the best performance and then we applied three or four PEQ adjustments by way of the Behringer 1000DSP amplifier used for the subs. Not bad considering there are no purpose-built bass traps in the room yet.
The important thing is that it sounds great!
Adjusting the subwoofer helped to smooth out response in the high end as well as you can see from this center-channel only graph. These graphs sure look bumpy but it really does sound exceptional in the room. Vocal clarity is excellent. You can see in this graph where the 120Hz rolloff down to the subwoofer takes place.
Now check THESE out. Look at the change in decay that has occured in the room since we first measured vs. now. The green waterfall is with nothing in the room except carpet... no Linacoustic, no furniture.
And this is what we measured this weekend (new carpet, 2" Linacoustic on screen wall, giant couch, giant ottoman, no other wall treatments)
Ideal? No. Better? Oh yeah!
Attention Defecit Version: The room sounde even better now thanks to tweaks and measurements after a visit from Nickshitachi!