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It's been awhile, but I finally got around to it today. The seating and riser definitely did affect the room response. Below is what the raw response looked like before the room changes (i.e. before any equalization). Red is pre-changes, Green is post-changes (with chairs & riser added).



After about an hour of tweaking, the BFD has again worked its magic and returned my primary listening position to a very balanced response (below):



The BFD is truly a wonderful little addition to the HT. It creates a clearly audible difference to me.

On the other hand, despite running multiple subs, my responses in the rest of the room varies pretty wildly (though better than when I just had one). Below is an eye chart of what the response curves for every seat in the room look like. Fortunately I only sit in one chair, my guests can suffer.

I'm guessing that would be the chair with the dark purple line ?

You got it... you passed the eye test.

Jason,

Actually, the post raw curve is kinda nice. I'll bet you could get a relatively flat response with only 2 filers:

38hz, .22 octave b/w, -7db
60Hz, .16 octave b/w, +6db

How many filters did you wind up using?

Hey Steve, good to hear from you again.

I managed most of the worst peaks/dips with just ~3 filters, but of course tinkered with it further until I had it looking like it does above... I think I ended up with ~10 filters, most of which were minor tweaks after the first few major adjustments.

It's admittedly a sickness I have that demands that I tinker to see how flat I can make the curve, even though I realize that beyond the first few, the audible difference is entirely negligible - but isn't the graph pretty?!

Jason

It is, nice and smooth! Just don't stick me in the teal chair if I ever come to visit.

I noticed your after chart takes an 8db hit at 20Hz (only about 2db before). Do you notice it when listening to music?

Is system tweaking an official illness?

Yes, but it's not extremely contagious. It seems only a few have the genetic makeup to succumb to it. It's rarely fatal but there is no cure. You can only learn to manage your illness and try to live a relatively normal life.

In medieval times, some physicians believed that you could catch a disease by looking at a sick person. Many modern day physicians discount the theory for this particular malady but do claim that you run the risk of infection by listening to another sick person's sound equipment. Simply reading about other peoples sound equipment is enough to act as a sort of reverse placebo which tricks the mind into lowering the bodies natural immune system and then you run a much greater risk of catching the disease when g exposed to sound equipment.

I actually didn't even notice that... Clearly my obsession to flatten the curve overrode the rest of the concerns.

This weekend I maxed out the time available simply making the equalization changes, so listening time thereafter was pretty limited. I suspect though that a dip at 20 Hz would not audible in most of the music I listen to. For movies though, it's definitely sub par...

Great, more tweaking ahead (after I told my wife I was done). :0 I'm sure she won't be that surprised to hear I was wrong.

Thanks for pointing out the dip in the curve, I should be able to boost it fairly easily with the BFD (if only its equalization went down to 15 Hz)

Jason

Is buying a book with the title "Master Handbook of Acoustics a sign of early onset of the disease?