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**hjones4841** · **02-06-09, 04:38 PM**

Here is the FR plot with the same setup as before, sub only but Audyssey turned ON. Note that I DID re-run Audyssey before these measurements to compensate for the added traps. Truly odd results; it seems that it is compensating for bass from the mains, since it set them to LARGE. Not even gonna bother with a waterfall for this one.

**hjones4841** · **02-06-09, 04:52 PM**

Now, BFD ON, Audysset OFF, sub only, no smoothing. 6 filters set on BFD. Not bad, not bad at all.

**hjones4841** · **02-06-09, 04:58 PM**

Waterfall for the above settings: Audyssey off, BFD ON, sub only. Looks like I picked up some ringing in the 30-60Hz range. Not sure why. Oh well, gonna listen to some music instead of sweep tones for a while.

**bpape** · **02-06-09, 05:19 PM**

Looking pretty good. Try broadening the Q of the EQ band you have between 30 and 40Hz.

Bryan

**hjones4841** · **02-06-09, 06:06 PM**

Yeah, I see that now. The last filter I set was a broad one centered at 20Hz to try to compensate for the LF rolloff in the BFD. I may have some overlap there. Makes sense that a narrow Q filter would cause electronic ringing, but perhaps not that much?

Also, I noticed as I was taking everything down that the ECM8000 was pointed almost horizontally, instead of vertically. I forgot to reposition it on the tripod after mounting the Denon mic to run Audyssey. That could account for some of the differences in the graphs after the first one that I posted.

Anyway, I had XM Watercolors Jazz playing from DirecTV for a while - very, very smooth bass response, especially on electric bass as it ran up and down the scale. Impressive difference.

I was going to mount the 3rd 42" trap from the ceiling above the fireplace, but was too tired. Wouldn't mind freeing up the floor space.

Do you think others would be interested in seeing pictures of the hanging Monster traps with a description of how I did it? I could start a new thread...

**bpape** · **02-07-09, 08:26 AM**

Pics are always helpful. I think this thread would be a good place for them though just to keep things together.

Bryan

**hjones4841** · **02-08-09, 03:57 AM**

Bryan: As noted in previous posts, adding the 3 traps after the first 2 made a huge difference. I might have room to put a couple more Monsters in the room in a month or so (maybe side walls at ceiling), but am wondering where the cost/benefit end point is in all this.

I read posts such as those by thewire and others that indicate the need for many traps in a small room such as mine. How do I judge how much is enough? Surely the waterfall plots indicate that some improvement can be made, but I have discovered during this work that subjective performance improvement is far greater than measurements suggest.

Thanks.

**bpape** · **02-08-09, 06:37 AM**

You're absolutely correct. You've made great strides in response and decay time. You're still using EQ to smooth the curve which is fine. Adding additional treatments may or may not improve the response depending on whether the position required is feasible. It will definitely help more with the decay time but be realistic about the ringing down in the 20's. That's just about impossible to completely deal with using any kind of sane treatments.

You're also correct that subjective improvements can be very different than just pure measurements. Many other things are impacted by getting the bass under control.

While I'd be stupid to not want to sell you more treatments, my recommendation right now would be to hold tight and live with this for a while and really get used to what each thing is doing for you. Then, you can move a couple of the things around and see what other positions might buy you while understanding what things are being caused by removing what you've just done.

At that point, you'll be better informed to make a good decision as to the cost/benefit of adding a couple more.

Also, remember that any EQ you've done now is only valid for this configuration. Move any of the treatments, move the seating, move anything else, and you'll need to start at 0 again for EQ and readjust accordingly.

Bryan

**hjones4841** · **02-08-09, 08:24 AM**

Sounds like a plan, Bryan. I need to pick up some R30 batts for the attic within the next 2-3 weeks (shoulda never allowed the builder to use blown-in!), so I may try laying a few above the ceiling tiles on the sides of the room before hauling them into the attic just to see what that does.

Thanks again for all your advice. I was really on the fence about traps until your phone call.

**bpape** · **02-08-09, 09:01 AM**

No problem at all. If you haven't done the drop ceiling yet, I'd definitely do that before doing anything else.

Bryan

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