[Hakka]

I've rearranged my room treatments and ran about 200 sweeps with REW.

After i posted the graph above I added some black curtains over the ceiling, sidewalls and rear wall, from the front of the room to about half way back, this deadened the room further. Video was good but I ended up removing half of the curtain so it only goes 1/4 of the way back and removed all the rear wall cutains.

I dont have diffusers so I mixed up the arrangement of my DVD racks, which seems to work ok.
I have another rack under construction for the rear, for now there is a wonky stack of DVDs there.

I now have diffusers on the sidewall and backwall primaries(LCR) and put some absorber panels on the ceiling primaries(LCR). There is also an absorber mounted above the rear diffuser to catch a reflection from the centre that bounces off the ceiling then off the backwall.
There are absorbers on the frontwall, one behind each main speaker, they are positioned slightly lower than ear height so they dont do much (if I turn them the other way they block the bottom of the screen). There are also absorbers on the sidewall next to each main. I attached some pics.

I have attatched impulse response graphs for all my speakers. The centre channel seems to disperse sound more towards the ceiling than the others, probably because of the horizontal placement. The reflections around 7 - 9ms are ceiling and ceiling>sidewall.

I also want to add some more side and rear diffusers for that spike in the mains at 9ms, and a better ceiling absorber for the centre.

I might have a go at some of those DIY QRD diffusers for the upper back and sidewalls.

I'm stuck with absorbers on the ceiling, I'm using thumb tacks and diffusers are too heavy if they land on my head.

I will post more graphs as I make changes.

Suggestions are welcome.

Hakka.