Looking for help from those with more acoustics knowledge about a problem that seems to have manifested recently. I'm getting some weird peaking in the 350-1,500Hz region that I know for sure didn't use to be there, and it's really bugging me. Only reason I remeasured is because I upgraded to Dirac 3 (from Dirac 1), and I wanted to see the differences in the bass response; otherwise, I wouldn't have noticed.
Below is MMM measurement. Dirac Live 3 is used to EQ everything below 300Hz. I've circled the problem area in green. Blue line is drawn in paint to show what I would consider to be a perfect response in my room. The problem didn't exist last year when I measured, and if anything there was a bit of a suckout in that same region. Honestly, I probably wouldn't care if I didn't know for sure that the problem didn't use to exist. It's also in perhaps the most critical range, and those are ~4dB peaks/dips, so I'm sure it's unfortunately very audible
.
I'm trying to think what could have possibly changed. Things I can think of:
1. There use to be a pretty heavy single seat recliner behind and to the right of the speaker. I've attached a photo. You can see there is just a small office chair there now.
2. GIK accoustic panels may have changed position slightly. I recently moved 12 of my GIK panels(ranging from 4" to 8") into the garage for an hour or so, just as a test to see if it would tame the overly bright sound of that system(it did). I forgot to take before pictures, though, so I had to rely on memory to try and put all the panels back in the exact same spot. I think it's mostly the same, but it's possible the panels are in slightly different positions. Could small differences really lead to that big of a change?
3. Acoustic curtains. You can kinda see in the attached photo(behind the office chair). I'm pretty sure those were present in my old measurements, but I can't say I'm a 100% sure.
4. Speaker placement and toe in might be ever so slightly different, but should be within an inch and a few degrees. Recently pulled it out to the middle of the room to do a mono comparison with my new Genelec speakers. I did put tape down to mark where it was before, but it's impossible to line it up "exactly". I highly doubt a tiny position difference could create such a large problem, but my acoustic knowledge is very limited.
5. Upgraded from Dirac 1 to Dirac 3. I'm only EQing up to 300Hz, though. Is it possible that the bass EQ is somehow affecting the ranges above?
Those are the only changes I can think of, and I honestly don't see how any of those could create such a drastic response error.
What can I do to try and fix this?
As mentioned, I've got a bunch of GIK panels I can work with. I don't care at all about aesthetics(as you can probably tell by the panels covering the fireplace
), so I can move them around anywhere I want. I've also got other panels I'm using in my office, garage, and bedroom that I could move to the main room, or I could always buy more. How effective would panels be for addressing peaking in this area?
I could also try extending the range of Dirac's EQ. Right now, I've got it limited to 300Hz, but I could probably bring that peak down by extending that to 1.5kHz or so. I'm a little hesitant to do this though after I test I did last year where myself and friends all preferred the limited range EQ over full range EQ. That test was done with Dirac 1, though, so maybe Dirac 3 is better at full range EQ. Writing it out now, I'm thinking this is something that I definitely need to test again, so I'll probably be trying this no matter what.
Finally, I guess it could be the speakers themselves, but that doesn't explain why it didn't use to be there. Also, there is a spin available, and I don't see anything that could cause this. There is a directivity error just below 500Hz(where the horn stops controlling directivity), but this starts at 350Hz.
Any other ideas?