Null and Void at 630 and it Hertz!

[toddalin]

Todd...

Have you tried a different amp? Maybe the Yamaha that you have has some sort of problem....or just doesn't like the 2205/2235. This is weird.

I highly doubt the room would mess around with that high a frequency...unless the room is really live, reverberant. Does the room "zing" when you clap your hands loud? Corner reflection/bounce?

Just a thought. I'm sure you're really frustrated.

Yes, I too assumed that it could be the amp (RX-Z9) leaving a sonic signiture, but tried another (DSP-A1) and even Grumpy brought a JBL amp over and ran it right off the computer all with the same result.

Like I noted, I can get the classic 2235 frequency curve with the mic lying on the floor.

Room does have one wall of large windows and a wall of "French" windows, but these are covered by heavy, light-proof shades. There is also a triangular window near the ceiling. Other walls are typical wall board with some artwork. Furniture is typical overstuffed. Room is approx 28'x16.5' and ceiling slopes from 16' to 8'

BTW, there is no suck-out when you talk in the room.

[pelly3s]

so i ran into this same kind of the issue working with a box a customer brought me the other day. the baffle was set back about 4 or 5 inches and when I added a piece of foam to the baffle on the sides of the woofer and it corrected the problem. i figured it was the fact that the distance the baffle was set in was about a 1/4 the wavelength at about 650hz. needless to say he pretty much just had to live with the problem if he wanted to use the boxes.

[Ian Mackenzie]

Yeah,

It could be one of the issues.

Ian

[grumpy]

I had suggested Todd might want to check that some time ago... I don't recall any specific results
(positive or negative)... easy enough to recheck next visit