I am getting the attached response after running Dirac in my "horrible dimensions" room (24 x 26)?

2016-03-28_20-33-55_suck_out by Jose Sifontes , on Flickr

I have tried many speaker positions. They are 4' from the back and side walls - this is where I get decent imaging. Bass traps helped a bit (it was worse) but I am still searching for options (short of building a false wall to change room dimensions - thought I may do that in the end). The subwoofer (not shown, in back of room) fills in where the Triton 1s drop out at 40hz, but I would like for the 1s to run full range and not depend on the sub so much. ANY IDEAS WELCOME!

IMG_1751 by Jose Sifontes , on Flickr

Since you've asked for any idea, have you tried increasing the bass level setting on the T1s? Another idea might be to remove the bass traps and position them closer to the wall. Lastly, consider how much faith you are giving the accuracy of Dirac.

Jose,

First of all, what a GREAT room! I could see spending hours in there with all those toys! You've got a lot of great gear and have done a great job setting it all up. It looks like an audiophile playground. Thanks for sharing your space with us.

Looking at your measurements, I'd say you have things in really great shape! Yes, there appears to be some issues at 49 Hz but the rest of the graph looks great. Count yourself lucky. What does the curve look like with all subs running?

My other question is regarding the bass traps. Those acoustic panels look a bit thin. Are you sure they are actual bass traps and manage bass down to 20 Hz? I have 4 bass traps from GIK and they look a lot thicker. GIKs thinner panels don't manage low frequencies well. I'd check the stats on those panels first and then play with placement. Based on your great frequency response now, you could create more issues than you solve. Just my .02.

Cheers,

T Cobe

Thanks. The dark brown columns to either side are corner traps using Ecose 3, 12"x12"x89", and there are additional traps to either side. I plan to add more as that is the one thing that helps- albeit slowly/incrementally.

I see the similar suck-outs on Room Eq Wizard using a different UMIK-1 calibrated mic. although they are not as pronounced on the REW sweeps, so you may have a point there - thanks!

Will continue experimenting with the T1 bass control and see what that does - if I discover anything useful will post here.

T Cobe wrote: Jose,

First of all, what a GREAT room! I could see spending hours in there with all those toys! You've got a lot of great gear and have done a great job setting it all up. It looks like an audiophile playground. Thanks for sharing your space with us.

Looking at your measurements, I'd say you have things in really great shape! Yes, there appears to be some issues at 49 Hz but the rest of the graph looks great. Count yourself lucky. What does the curve look like with all subs running?

My other question is regarding the bass traps. Those acoustic panels look a bit thin. Are you sure they are actual bass traps and manage bass down to 20 Hz? I have 4 bass traps from GIK and they look a lot thicker. GIKs thinner panels don't manage low frequencies well. I'd check the stats on those panels first and then play with placement. Based on your great frequency response now, you could create more issues than you solve. Just my .02.

Cheers,

T Cobe

Thank you T Cobe! I do enjoy my cave a lot, for music and video. The panel bass traps are of varying depth - some of the 24x48 panels are 6" thick, most are 4" and one is 2". There are also corner sofit traps 12x12x89". All made positive impact on the bass - the graph looked worse before. Will continue adjusting trap placement.

I may be giving too much attention to the 40hz suckout, but I thought I would ask here. The curve improves a lot after Dirac adjusts it. Another angle of the room showing the corner sofit traps:

IMG_1752 by Jose Sifontes , on Flickr

And the equipment stack:

cave (2 of 2) by Jose Sifontes , on Flickr

Wow lots of toys, looks awesome.

I had similar looking response as yours. www.goldenear.com/forum/Show-Off-Your-Go...f-a-work-in-progress
Actually yours looks way better other than the null at 40. I have since moved the subs on mine and achieved a much flatter starting point prior to running room correction software. I posted new graphs showing how I basically removed my null at 48hz, but its not been approved yet so isn't showing up.

I'm hardly an expert as I've just been learning this as I go and experimenting. But this site helped find better placement for my subs. www.padrick.net/LiveSound/CancellationMode.htm
Which according to it if you're having a cancellation at 40hz means the boundary condition causing it is around 7' away from the speakers. Your ceiling would be my guess. I'd recommend placing two of the wall panels that you currently have on the front wall and try them on the ceiling at the reflection points between speakers and main listening position as an experiment and see if that reduces it.

I've not used Dirac but I have used REW. The chart shows just the left and rights without the sub, and from the picture it looks like you also have LFE going to the Tritons. I assume the posted graph is Left + Right in a 10-20k sweep without sub channel? Does it flatten out when you run the fronts and the sub together? You could run them as I now currently do, without LFE, set to large so they run full range, and use your external sub to handle LFE duties. Then place the sub on its own based on where the graphs show the flattest response.

From what I've read bass traps below 100hz are not great since they need to be like 6' thick at that frequency to do anything. At that point the recommendation is to add multiple subs to cancel the nulls and EQ's like MiniDSP or Dirac to lower the peaks. You can try adding an EQ boost at 40hz to see if its an eq correctable 'dip' vs a room mode 'null'.

Good Luck

Edit: just looked at the pic again, you dont have LFE going to them.