Acoustics tips and help, please

**atledreier** · **01-06-08, 04:19 AM**

I've been hijacking so many threads in this forum I think it's time to start my own.

My room:
390cm wide by 530cm long, 230cm ceiling.
Floor is concrete (basement) with laminate wood on top. Walls are panelled wood(sp?) for the sides and ceiling. Front wall is plaster with wallpaper, and rear wall is plaster/wallpaper, but with a big glass door to my office.
Some carpeting on the floor, and three bookshelves with books and DVDs. A dysfuntional fireplace and a bit of clutter as well.
A three seat sofa is pretty much all the furnishing in the little room.

There is a 3' opening to a hallway and stairwell in the right wall, just rear of the 1st reflection point. That is covered with a light drape.

My system is off center in the room, after advice I got here, and it works really well. Smoothed out the response and kept imaging, so I'm happy with it. That also made access to the back of the room better.
I have my subwoofer located behind my listening position.

I have in total 5 sheets of 1,5" rockwool acoustics panels, and 3 sheets of 4" Rockwool.
I have treated the sidewall 1st reflection of both fronts with 1,5" panel, and also the reflection off the front wall with 1,5" panels. The 4" panels and a 1,5" panel are straddling corners as basstraps.

I have more acoustic panels on the way, and will make proper floor to ceiling bass traps in every corner of the room.
I have some nasty dips in my response, and I wouldl liek to have them smoothed out. I have had my current setup for about two months now, and I think my house curve might need some adjusting, there's just too much low-end level now. I have a +10dB hard knee curve. It's very cool to have my sofa shake and jump around for action movies, but sometimes it just gets too much. I think I'll try to go with +3dB and live with that for a while and go from there. Or it could be that it's just a little bloated from too long decay or something. I don't really know. I've also though about maybe making some diffusors. I don't wan the room too dead, but I'm an imaging nut, so I want crisp and sharp without being harsh. I know my components can do that, so it's all in the room.

Anyways, maybe some tips to what I can do better? I can post any measurement you like, including REW and trueRTA, so just let me know what you need to assess my mess..

A picture says a thousand words, so here comes a few thousand words worth of pictures of the room. I had no thought for proper photography when I took these, so bear with me..

My current sweetspot response in green here:

**Ethan Winer** · **01-06-08, 12:30 PM**

Quote:

atledreier wrote:

maybe some tips to what I can do better?

Nice sub, that's the same one I have. Mine is in a corner though, and it absolutely rocks there!

The biggest problem I see is the reflecting doors not far behind your head. You really need absorption there - the thicker the better. Maybe panels on stands?

--Ethan

**atledreier** · **01-06-08, 12:38 PM**

You should feel it in a nearfield position like I have it...

I am not too fuzzed about aestethics.. Maybe I could hang some panels on the doors themselves?

Even though I use it for HT, the main concern is overdampening the room. I listen most critically to music. Maybe some diffusion somewhere?

**Ethan Winer** · **01-06-08, 01:43 PM**

Quote:

atledreier wrote:

You should feel it in a nearfield position like I have it...

Mine rattles the floor on some movie scenes. What more could a bass-lover ask for?

Quote:

Maybe I could hang some panels on the doors themselves?

Sure.

Quote:

the main concern is overdampening the room. I listen most critically to music. Maybe some diffusion somewhere?

Looking at your photos I don't think that's a problem.

--Ethan

**atledreier** · **01-06-08, 03:41 PM**

I could post an IR plot too, maybe that will give some hints. I have a slight focus problem. The soind is very transparent and holographic, but not very sharp.

**atledreier** · **01-18-08, 09:23 AM**

Ok, got my panels just now. Going to get the materials and wood I need to get some cornertraps going. Hopefully done over the weekend. I have moved some stuff around, mainly the subwoofer, and the fronts are symmetrical again. Not sure I like it, I'm going to give it a little time and see if I just need to 'unlike' my old setup..

**atledreier** · **01-23-08, 05:35 AM**

Ok, I have 4 cornertraps done. Not as effective as I'd hoped I think, but i'll keep using them and see if I discover the true performance.

**John N** · **01-23-08, 06:39 AM**

How would it sound with a nice ottoman instead of the coffee table?

**atledreier** · **01-23-08, 06:48 AM**

Send me one and I'll tell you!

i'm currently considering ceiling treatment. Will try some stuff tonight, both placement, treatment and actually listening to stuff..

**atledreier** · **05-18-08, 10:26 AM**

I just finished three more acoustics panels. My four corner chunks were located stacked in the front corners before. Now I have one in each corner, with a 4" panel straddling the corner on top of each of those. That means floor to ceiling basstraps in all four corners! And it really made a difference too! I have another set of small-ish corner chunks that I'm going to finish up today and see if I can find a use for. I'll probably replace two of the corner-straddling panels sith the chucks and use the panels somewhere else. I have another two panels that I need fabrick to cover, so they will come at a later stage. I'll get fabrick tomorrow, probably. Those will go in the ceiling to kill the 1st reflections from LCR. They are also 4".

So now I have 4" panels behind the mains, 3" behind the center, 1,5" on sidewalls, and chunks in all four corners, floor to ceilig! And it sounds rather good to my ears!

**atledreier** · **05-19-08, 04:05 PM**

Ok, finished all the materials I have so far. I'd like some input as to the most effective use of the stuff I have. So I'll list it all;

5 pcs 1 1/4" 2'x4'
6 pcs 4" 2'x4'
4 pcs 3'4" corner chunks, 2' face
2 pcs 2'6" corner chunks, 2' face

Currently I have the 4 larger corner chunks on the floor in each corner.
In the front corners I have one 4" panel straddlign the corner on top of the chunks, so they fill floor to ceiling.
In the rear corners (where I have my sonotubes) I have the smaller chunks stacked on top of the larger chunks, with one 4" panel straddling the corner in front of the smaller panel (if that made any sense).

One 4" panel in the first reflection point from the left speaker. This covers the reflection from the center as well, on the left wall.
Three 1 1/4" panels stacked in front of each other, making one 3 3/4" panel on the right wall in the first reflection from the right speaker. I have a door here that prevent me from killing the center channel reflection on the right wall. I'll live.

Two 4" panels upright against the front wall behind the main speakers, and two 1 1/4" panels next to those, toward the center, and the last 1 1/4" panel horizontal behind the center speaker. So my front wall is covered up to 4' high with at least 1 1/4" and up to 4" (some of the front wall panels overlap)

I plan to get another case of three 4" panels and mount them in the ceiling to kill the 1st reflection from the left, center and right speakers.

The room sounds awesome as it is now. Going floor to ceiling really helped, as opposed to the 6' stacks I had before. Ceiling height is just over 7', but covering that last foot really helped.

I feel maybe having the small chunks behind the 4" panels is overkill and could be put to better use, but then the subs are right against those corners and I figure they can use all the absorbtion they can get back there.

Any views or suggestions as to what I should do? I enjoy the room as it is now, but things can only get better, right?

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