Plasma Cover with Sonex foam?

Mightyburner · « **on:** 24 May 2007, 01:55 pm »

Living in an apartment, I have no choice but to have my equipment rack and 43" plasma centered between my front speakers. My living room is 26x13 and I have a long wall set-up, which forces me to have my sofa right against the rear wall. To deal with room reflections I have an ASC (diffusion) matrix panel behind my head and this has helped a great deal with cutting down on the reflections and improving overall imaging with both my 2-channel and HT set-ups. When I use my 2-channel system, I typically throw a small blanket over the TV.

Rather than use a blanket, a seamstress friend has agreed to make a cover for the Plasma to further help with reducing room reflections. I'm wondering if it would be beneficial to insert some type of acoustical foam like Sonex in the cover.

Given that I only need one sheet, the Sonex products seem a little too expensive for my needs. Are there any other cost effective options?

Any opinions would be appreciated.

JoshK · « **Reply #1 on:** 24 May 2007, 02:11 pm »

I'd think if you can get your hands on some industrial felt, that would work a treat. McMaster & Carr carries an industrial wool felt up to 1/2" iirc that would work great. It isn't super thick but is what "the pro's" use in speaker diffraction control, etc. It won't do anything for bass freq, but then nothing short of bass tubes in front of your TV would, and I am not sure it is even necc in this position.

Warning, that stuff is not cheap! But I think you could get it close to the size you need and have your seamstress friend make a very functional and attraction solution. Who knows, you may end up with a marketable product.

I would guess it would work better than foam and look a hell of a lot better.

JoshK · « **Reply #2 on:** 24 May 2007, 02:18 pm »

Here is the link...
http://www.mcmaster.com/nav/enter.asp?partnum=8241K151&pagenum=3376

I got the white 1/2" thick F10 (the real wool is what you want, not the synthetic). It comes in different sizes. I'd suggest getting the 6' wide sheets where the length is equal to the height of your plasma and then cut off the extra width from the 6'. That scrap can then be made to make super effective diffraction control for your speakers that will seriously improve the imaging of your speakers.

machine · « **Reply #3 on:** 24 May 2007, 02:29 pm »

My setup is similar, how important is covering up the screen?

In my case it's a wall mount 42" LCD pannel.

Have been thinking about doing something for a while.

Inital thought was to make something out of some 2" mineral wool sheets (2' x 4') I got for 1st point reflection control.

Sort of a frame that would go around Screen, would attach at top with wood strip monted on wall - like how A/V-1RS from GR Research is mounted (http://www.gr-research.com/kits/av1rs.shtm):

"There is an MDF strip that has a 45 degree angle cut across the top that mounts to the wall. The back side of the speaker has a reverse cut 45 degree angle edge that slips down over it. See the side view for a better look at this simple mounting design. "

Depending on depth, there might be space between the screen and back of pannel to help absorb sound.

JoshK · « **Reply #4 on:** 24 May 2007, 02:43 pm »

I think your idea will/should work well too. It just might be a bit thicker, and depending on the SAF, they may fly or not. I am sure it could be made to be attractive.

As far as how important. I think you'd be surprised. Get a thick blanket and hang it over the plasma and see if you can tell the difference. That will give you an idea.

Mightyburner · « **Reply #5 on:** 24 May 2007, 05:48 pm »

Thanks for the link JoshK.

I got tired of the blanket becuase not only does it look like,,,well,,, a blanket, it kept slipping off. I'll make sure to post some pics when I get it finished.

ooheadsoo · « **Reply #6 on:** 24 May 2007, 06:09 pm »

Just so you know, the wool starts falling apart after about 2-3 years (in my case.)

1000a · « **Reply #7 on:** 24 May 2007, 06:16 pm »

excellent post with so many of us using the same room for film and music. I will have to try again but when I put a comforter over my LCD screen it sucked the life out of the sound stage. will do test again, my findings don't seem to jive with others!

FWIW my screen is not shiny at all I would call it a flat finish

brj · « **Reply #8 on:** 24 May 2007, 06:36 pm »

By a "cover" are you talking about something that is blanket-like in construction, but specifically fitted to the TV rather than randomly tossed over it? If so, I wonder if you could create a fitted quilt that uses mineral wool or fiberglass insulation as the batting? (If you use fiberglass you'd want another layer of some kind to seal in the loose fibers so they can't escape, especially since you'll be moving and handling the cover on a regular basis.)

Mightyburner · « **Reply #9 on:** 24 May 2007, 06:47 pm »

Quote from: brj on 24 May 2007, 06:36 pm

By a "cover" are you talking about something that is blanket-like in construction, but specifically fitted to the TV rather than randomly tossed over it? If so, I wonder if you could create a fitted quilt that uses mineral wool or fiberglass insulation as the batting? (If you use fiberglass you'd want another layer of some kind to seal in the loose fibers so they can't escape, especially since you'll be moving and handling the cover on a regular basis.)

I was thinking about something like a Sonex foam like padding with a fitted decorative cover or fabric (e.g., jute or kuba). A member of Audiogon suggested I try foambymail.com

Ethan Winer · « **Reply #10 on:** 25 May 2007, 04:34 pm »

Quote from: MMMiles on 24 May 2007, 06:47 pm

A member of Audiogon suggested I try foambymail.com

Stay far away from FBM. See this:

www.ethanwiner.com/fraud.html

--Ethan

DTB300 · « **Reply #11 on:** 25 May 2007, 06:13 pm »

Quote from: MMMiles on 24 May 2007, 06:47 pm

A member of Audiogon suggested I try foambymail.com

Send me the money you are going to spend on the FBM stuff and you will get the same amount of benefits for your room - nothing.

Heed Ethan's words about FBM and purchase Real Traps or GIK stuff. Both offer great products and great support.

Dan

nathanm · « **Reply #12 on:** 25 May 2007, 06:45 pm »

They aren't THAT bad. Foambymail's foam is like getting the sandwich out of the vending machine. It's cheaper than the restaurant, it's not totally delicious, but it IS an edible sandwich nevertheless. To say that it will do NOTHING is not fair. It will undoubtedly absorb sound. I've put squares of foam used for packing electronics that I got for free from a friend on my wall and it did work, it knocked down the slap echoes. We're talking about treble here, very high treble. Foam is not gonna solve your bass problems. Bass costs big money.

My front wall is all Auralex and the side walls are foambymail. Auralex is noticeably firmer and is precision cut. FBM is softer and cut sloppily, but it's better than bare drywall. Auralex comes in a giant box, FBM is vacuum sealed and scrunched into a cylinder. I don't have any comment about disreputable business practices, I'm only giving my opinion based on using the stuff. If you want to go full bore undoubtedly go with the pro stuff. But if you're a cheap bastard like me foambymail will not be the end of the world.

Mightyburner · « **Reply #13 on:** 25 May 2007, 09:42 pm »

Just to be clear, I'm not trying to cover add a significant amount of treatments to my walls to wife and something about cutting off my,,,.

I'm just guessing that if I make some sort of fitted cover/quilt that has acoustic foam or whatever inserted into it that it would work better than me throwing a blanket over the TV everytime I listen to music. I understand that at some point I'll have to get bass traps but that's another battle for another time (or house).

Ethan Winer · « **Reply #14 on:** 26 May 2007, 01:13 pm »

Nathan,

Quote

To say that it will do NOTHING is not fair.

Yes, it does do something - about 1/3 what they claim.

Quote

if you're a cheap bastard like me foambymail will not be the end of the world.

This brings up an interesting point. If you know someone is dishonest, would you want to reward them by buying from them even if you understand what you're getting and aren't put off by an inferior product? This is the issue for me, not that FBM is "good enough" to use in a non-critical application.

--Ethan

1000a · « **Reply #15 on:** 4 Jun 2007, 06:02 am »

did she do the job yet? I certainly second the fiberglass panel, here is a link where you can buy just one panel: http://www.atsacoustics.com/cat--Fiberglass-and-Mineral-Wool-Batts-and-Boards--106.html

if you think the FB panel is to flimsy it can be reinforced by putting or gluing a piece of foam core behind it. foam core is a common item in an art supply store cuts w an xacto kife, can also buy 1 at a time-cheap.

this is cover i am doing for my flat TV: [=burlap front, a=poly batts, b= FB panel, c= foam core, ]= burlap to close the sleeve, _______ = top hinge part & sides, ]= back piece of burlap
____
[abc] ]

seems complicated it is not its a sandwich that goes inside a burlap inner sleeve thats part of the cover, all materials are very cheap. other than burlap (lots of colors these days - Joann Fabrics) most materials are not transparent enough to let enough highs and mids thru, you can get some but it will cost you. Do not believe people in a fabric shop, John Risch has already tested other materials. trouble is most of it reflects the highs and mids, exactly the problem we are trying to correct.

hope this helps, if anyone has different or better ideas for mine I am interested- have not started my project yet- thanks in advance.

bpape · « **Reply #16 on:** 4 Jun 2007, 10:53 am »

I would have to agree that the FBM is for all intents and purposes worthless. Ethan hit the nail on the head - it does something - costs you money. It might do something in the kHz range but that's about it. ESPECIALLY where you're trying to get something accomplished with as little disturbance to the room as possible (in order to keep the family jewels in tact) you'd want something that does as much as possible.

Bryan

Ethan Winer · « **Reply #17 on:** 4 Jun 2007, 01:33 pm »

Quote from: bpape on 4 Jun 2007, 10:53 am

ESPECIALLY where you're trying to get something accomplished with as little disturbance to the room as possible (in order to keep the family jewels in tact) you'd want something that does as much as possible.

That's an excellent point Bryan. In situations where minimal visual intrusion is important, you want the get the most performance from each piece.

--Ethan

Levi · « **Reply #18 on:** 4 Jun 2007, 02:43 pm »

Hi there,

I think we have similar setup with the couch right against the wall. I use a heavy wool blanket sparingly. Lately, I just left it uncovered.

I'd like to get one of those ASC (diffusion) matrix panel though.

Regards,
Levi

Quote from: MMMiles on 24 May 2007, 01:55 pm

Living in an apartment, I have no choice but to have my equipment rack and 43" plasma centered between my front speakers. My living room is 26x13 and I have a long wall set-up, which forces me to have my sofa right against the rear wall. To deal with room reflections I have an ASC (diffusion) matrix panel behind my head and this has helped a great deal with cutting down on the reflections and improving overall imaging with both my 2-channel and HT set-ups. When I use my 2-channel system, I typically throw a small blanket over the TV.

Rather than use a blanket, a seamstress friend has agreed to make a cover for the Plasma to further help with reducing room reflections. I'm wondering if it would be beneficial to insert some type of acoustical foam like Sonex in the cover. Given that I only need one sheet, the Sonex products seem a little too expensive for my needs. Are there any other cost effective options?

Any opinions would be appreciated.

Levi · « **Reply #19 on:** 4 Jun 2007, 02:48 pm »

I remembered Phil used some RPG type to cover his Plasma.