# HT Carpet in and finally measured! Thoughts??



## cdy2179 (Mar 2, 2008)

Ok, well I finally got carpet in the HT. I have 4 SI HT18s (one in each corner). Each 12 cubes tuned to around 17hz.

My build thread is below for anyone that wants to see the room layout.
http://www.avsforum.com/forum/19-de...ion/2023753-another-build-thread-no-name.html

I broke out the Umik-1 and got to work. First off xt32 had it kinda jacked up so I of course used the Inuke DSP3000 DSP to get it "perfected". XT32 also kept getting the sub distance wrong and put a null at the crossover... A HUGE null. I adjusted the phase (using distance) and fixed it. Bottom line you can't count on room correction to get everything right. It sounds light years better.

So anyways... How does my waterfall look? It looks very good IMO from 20k down with a great decay (not pictured), below is only the sub of course. However 35hz and down I think needs more bass trapping? Thoughts? I took measurements cranked up to 110db as well, just didn't take pics... still had plenty of headroom and not close to clipping.

Ohh and yes I set the high pass (thanks LTD) around 16 hz but room gain is kicking it!

Sorry I was in a hurry and taking so many measurements I should have used the capture button instead of taking photos.










I zoomed out to 800ms to see what was happening below 35hz










Is that a decent waterfall? 
What is considered really good decay time down low? I know it's not easy to control very low Frequencies. I am using my stage as a bass trap and also have a roll of insulation on top of each front corner sub.


Here's 200hz an up for the center....this one does have smoothing (I'm not at home so I cant play around with REW).










It looks like I'm down 25db in the first 120ms. I need to check out the rt60 tab tonight. 

This was a 60hz xover with smoothing.. this was me settling on a distance. Yellow was xt32 setting with smoothing.. 12db down at the bottom....sounded horrible.









I probably do need to spend more time with REW tweaking. I kinda rushed through things some. I definitely need to underlay sub and main spl and make sure I'm not getting any deconstructive response around the crossover.


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## Wayne A. Pflughaupt (Apr 13, 2006)

A 3-400 ms window on the waterfall would be more telling. If you can get the signal fading down to 35 dB in that range, you’re doing really good. :T

BTW waterfalls have no value above ~300 Hz.

Regards, 
Wayne


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## bpape (Sep 14, 2006)

A few small blips in the range you could actually treat but overall not bad on the waterfall.


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## cdy2179 (Mar 2, 2008)

I don't have recliners yet. I do have 2 huge 6' bean bags (cloth sacks) coming for the front kids row. I'm wondering if they may help tighten the bottom a little. I'll have to measure and see.

Currently I'm using gaming chairs..hey better than the floor.










Tonight I'm going to look at the rt60 graph. The bass sounds really good once I fixed XT32s sub distance which was way off causing a huge 12db null at xover.

Looking at the waterfall I'd guess the rt60 is around 350ms for most of the loudspeaker range. I have noticed my speakers just aren't imaging as well as they did prior to carpet, nor sounding as spacious. Although I also toed them in where as before the were aimed straight forward.

Here's an pic right after they were installed


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## cdy2179 (Mar 2, 2008)

bpape said:


> A few small blips in the range you could actually treat but overall not bad on the waterfall.


Really? So would you say that's a good end result? I looked at it and thought it looked quite bad even though it sounds very good to me. I'm hoping furniture may help in the 30-40hz range. Two of these are on the way.

http://www.amazon.com/gp/product/B008RKOL9G?ref_=redir_mobile_desktop&ref_=shptrk_scth

I also used my stage as a bass absorber and I have rolled up insulation sitting on top of each front sub. I had it laying around and figured it couldn't hurt.


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## cdy2179 (Mar 2, 2008)

I took some rt60 responses last night. I've got some issues. I'm kinda confused why I have 150-250hz area hanging around. My ductboard is around .5 absorption at 250hz. Of course my mains cross to the woofers at 500hz so they lose the directivity of the waveguides.

The room is also a little deader than I wanted.. I was shooting for 350ms or so... but maybe it's good? This is my first time getting this involved with my room. The last HT room I Eq'd the sub, threw up some panels and never checked anything.


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## Owen Bartley (Oct 18, 2006)

Steve, great looking room, and I love that screen wall shot (without the screen). Keep tweaking what you have now and you'll get everything dialed in in no time.


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## Talley (Dec 8, 2010)

Hmm... I'm taking a different approach. You have imaging problems and speakers not sounding as "spacious"... well thats because absorption is a black hole to sound. Your ears need comb filtering.

I'm going with 80% diffusion treatment and only a very minimal amount of absorption. This should increase my soundstage dramatically.


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## cdy2179 (Mar 2, 2008)

Talley said:


> Hmm... I'm taking a different approach. You have imaging problems and speakers not sounding as "spacious"... well thats because absorption is a black hole to sound. Your ears need comb filtering.
> 
> I'm going with 80% diffusion treatment and only a very minimal amount of absorption. This should increase my soundstage dramatically.


I actually have superb imaging. I can run phantom and I don't even miss the center... but of course I use it. The soundstage is huge. Unlike the pic above my mains are toed in.. that was before I talked to QSC and they assisted with aiming them.

Initially the room sounded too dead. Then I realized my dish receiver was set to auto leveling and it was squashing all of my dynamics (we DVR lots of series). Now it's really sounding awesome. Music is just awesome, vocals everything is just great.. My rt60 is still a little faster than I'd like but still within acceptable range. I figure I have about 20% of the walls with absorption.

I am absorbing the side reflections and sure If I could A/B the absorption vs diffusion I may have liked the mixture better. But of course diffusion is only suggested for speakers with really good off axis (Toole,Erskine etc)... I couldn't find those measurements for my speakers so I figured I treat the room for anything. That and I've already had all absorption panels in the past and love them.

But sure If I had gone with hanging panels again that could easily be removed I'd dabble in diffusion as well. Another thing to keep in mind is that this is a 7.4.4 system, I never run two channel, this is movies, gaming only, although testing it out it sounds great.


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## cdy2179 (Mar 2, 2008)

Owen Bartley said:


> Steve, great looking room, and I love that screen wall shot (without the screen). Keep tweaking what you have now and you'll get everything dialed in in no time.


Thanks Owen. I'll be ordering seats soon, then I'll do the final tweaking and take some good pics. I love that shot too, I really hated having to cover up those beast... I love the way they look in the baffle wall.


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