Acoustical Treatments Master Thread - Page 382 - AVS Forum | Home Theater Discussions And Reviews
Baselworld is only a few weeks away. Getting the latest news is easy, Click Here for info on how to join the Watchuseek.com newsletter list. Follow our team for updates featuring event coverage, new product unveilings, watch industry news & more!



Forum Jump: 
 176Likes
Reply
 
Thread Tools
post #11431 of 11453 Old 07-27-2016, 04:58 AM
AVS Special Member
 
myfipie's Avatar
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 1,047
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 63 Post(s)
Liked: 68
Quote:
Originally Posted by Tom Riddle View Post
No, they are 20' high, and my wife is barely on board with putting traps in the front. I got a hold of GIK and ATS, and they both suggested I just stick to bass traps behind the towers and the center due to my constraints. My room is not an ideal space due to being so open, so I will go with any improvement until I can build a dedicated space.
Yes that is a lot of blank wall area so you will naturally have a lot of upper frequency reflections (reverb). In the future, I would get some absorption (or diffusion) on the upper wall areas.

Glenn Kuras
GIK Acoustics

http://www.gikacoustics.com

myfipie is offline  
Sponsored Links
Advertisement
 
post #11432 of 11453 Old 07-27-2016, 11:22 AM
AVS Special Member
 
Tom Riddle's Avatar
 
Join Date: May 2010
Location: Greater Houston Area - Texas
Posts: 1,233
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 441 Post(s)
Liked: 382
Thanks @myfipie . Unfortunately, those areas have been deemed off-limits by my wife. I do have two bass trap panels coming in from GIK, so we will see how that helps. I did have a contractor come in to see about finishing the upstairs media room - so I'm on the way at least. My wife is trying to steer me from adding a pool and just finishing that room. That's how tired she is of my HT hobby, lol.

Klipsch RF-7 II's, RC-64II, RS-62 II's, RS-52 II's
PSA V3600I
Marantz SR7008 with TK421 Modification
Emotiva XPA-5
Sony XBR-75x940c with Ideal-Lume Panelight
Samsung PN64F8500 (Master Bedroom)
Tom Riddle is offline  
post #11433 of 11453 Old 07-28-2016, 08:03 AM
Advanced Member
 
Join Date: Sep 2015
Location: Europe, Croatia
Posts: 728
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 430 Post(s)
Liked: 190
Hey guys.
Are tuned membrane traps very effective for treating SBIR? I have a huge notch in response at 135 Hz which I believe is SBIR and would try to treat it by putting membrane trap at right location. Broadband panels don't help much.

Revel Ultima Salon 2, Revel M106, Revel C208, Yamaha P5000S, Denon X5200, Panasonic 65" VT50, SVS PC13-Ultra
Kef LS50, Parasound New Classic, Focusrite 2i2
donktard is online now  
post #11434 of 11453 Old 07-28-2016, 11:04 PM
AVS Special Member
 
Roger Dressler's Avatar
 
Join Date: Jul 2000
Location: Oregon
Posts: 9,837
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1464 Post(s)
Liked: 673
Quote:
Originally Posted by donktard View Post
Are tuned membrane traps very effective for treating SBIR? I have a huge notch in response at 135 Hz which I believe is SBIR and would try to treat it by putting membrane trap at right location. Broadband panels don't help much.
Is it a side wall or ceiling bounce issue? A diagram or picture might help to confirm. But aside from that, it might more effective to diffuse the reflection. Just a thought.

Deadwood Atmos theater [HTOM]
AV7702 Atmos 7.4.4, SSP-800 PLIIx 7.4
Aerial Acoustics 7B/CC3B fronts, B&W CWM8180 surrounds, Tannoy Di6 DC heights, Hsu ULS-15 subs
Roger Dressler is online now  
post #11435 of 11453 Old 07-29-2016, 05:42 AM
Advanced Member
 
Join Date: Sep 2015
Location: Europe, Croatia
Posts: 728
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 430 Post(s)
Liked: 190
Quote:
Originally Posted by Roger Dressler View Post
Is it a side wall or ceiling bounce issue? A diagram or picture might help to confirm. But aside from that, it might more effective to diffuse the reflection. Just a thought.
My left speaker is very close to the side wall and also right below slanted ceiling. That (slanted ceiling mostly, I believe) causes pretty chaotic response from 120 to 700 Hz (unlike on right speaker), but my movement options are pretty much non-existent.
I have early reflections treated, but my room configuration makes it kinda difficult for me to figure out the solution. Today I will try to play sine wave at offending frequency while measuring SPL at MLP and move acoustic panels around to see if anything will make a difference.

Also, how do you diffuse 135 Hz?

Revel Ultima Salon 2, Revel M106, Revel C208, Yamaha P5000S, Denon X5200, Panasonic 65" VT50, SVS PC13-Ultra
Kef LS50, Parasound New Classic, Focusrite 2i2
donktard is online now  
post #11436 of 11453 Old 07-30-2016, 02:35 PM
AVS Special Member
 
Tom Riddle's Avatar
 
Join Date: May 2010
Location: Greater Houston Area - Texas
Posts: 1,233
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 441 Post(s)
Liked: 382
Got my panels in from GIK today - put them in temporary spots just to test, but will take measurements and move to the best spot later. I used TDKR as my demo, and I noticed a significant improvement right away. The bass is much more potent, with little reverb off the front wall, and all the rattles that were in the equipment rack are gone. Very nice! My wife hates them though - she is ready to call the contractor today and start on my HT room, lol. The contractor is coming back by on Tuesday with his structural guy to finish out my quote.
dnoonie likes this.

Klipsch RF-7 II's, RC-64II, RS-62 II's, RS-52 II's
PSA V3600I
Marantz SR7008 with TK421 Modification
Emotiva XPA-5
Sony XBR-75x940c with Ideal-Lume Panelight
Samsung PN64F8500 (Master Bedroom)
Tom Riddle is offline  
post #11437 of 11453 Old 08-01-2016, 07:03 AM
Advanced Member
 
ddigler's Avatar
 
Join Date: May 2013
Posts: 829
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 349 Post(s)
Liked: 109
Good morning all; hoping some of you room treatment experts can help me; I have some great advisers at my build thread but with some of the evolving/contradictory info regarding room acoustics I am soliciting as many viewpoints as possible: Regarding front wall (behind false wall) treatment: is the recommendation to make this area completely dead with absorption still the commonly accepted approach (for movies viewing in particular)?

Last edited by ddigler; 08-01-2016 at 08:25 AM.
ddigler is online now  
post #11438 of 11453 Old 08-01-2016, 08:39 AM
AVS Special Member
 
HopefulFred's Avatar
 
Join Date: Mar 2007
Location: Atlanta, GA
Posts: 3,554
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked: 405
Reflected sound from the area of the image provides no benefit. In most cases, it is detrimental to both the frequency response and temporal precision of the front soundstage, as well as complicating management of the surround sound field. A baffle wall with surface absorption continues to be the gold standard, in my opinion.
HopefulFred is offline  
post #11439 of 11453 Old 08-01-2016, 09:26 AM
Advanced Member
 
ddigler's Avatar
 
Join Date: May 2013
Posts: 829
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 349 Post(s)
Liked: 109
ddigler is online now  
post #11440 of 11453 Old 08-05-2016, 09:26 AM
AVS Special Member
 
myfipie's Avatar
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 1,047
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 63 Post(s)
Liked: 68
Quote:
Originally Posted by donktard View Post
Hey guys.
Are tuned membrane traps very effective for treating SBIR? I have a huge notch in response at 135 Hz which I believe is SBIR and would try to treat it by putting membrane trap at right location. Broadband panels don't help much.
Basically yes, but you have to put them in the right spot and it still does take some area (wall area) to fix. You can't just put a 2'x2' tuned panel on the wall and think it will fix the problem. Needless to say through broadband should work if thick enough. How thick are the panels you have now?

Glenn Kuras
GIK Acoustics

http://www.gikacoustics.com

myfipie is offline  
post #11441 of 11453 Old 08-05-2016, 02:28 PM
Advanced Member
 
Join Date: Sep 2015
Location: Europe, Croatia
Posts: 728
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 430 Post(s)
Liked: 190
Quote:
Originally Posted by myfipie View Post
Basically yes, but you have to put them in the right spot and it still does take some area (wall area) to fix. You can't just put a 2'x2' tuned panel on the wall and think it will fix the problem. Needless to say through broadband should work if thick enough. How thick are the panels you have now?
I got 4" thick panels. I solved the problem partially today. I played 135 Hz tune and fixed SPL meter in place and then moved panels around until I gained some SPL

Revel Ultima Salon 2, Revel M106, Revel C208, Yamaha P5000S, Denon X5200, Panasonic 65" VT50, SVS PC13-Ultra
Kef LS50, Parasound New Classic, Focusrite 2i2
donktard is online now  
post #11442 of 11453 Old 08-09-2016, 06:04 AM
AVS Special Member
 
myfipie's Avatar
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 1,047
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 63 Post(s)
Liked: 68
Quote:
Originally Posted by donktard View Post
i got 4" thick panels. I solved the problem partially today. I played 135 hz tune and fixed spl meter in place and then moved panels around until i gained some spl :d
nice!!!

Glenn Kuras
GIK Acoustics

http://www.gikacoustics.com

myfipie is offline  
post #11443 of 11453 Old 08-09-2016, 10:07 PM
AVS Special Member
 
Skylinestar's Avatar
 
Join Date: Jun 2008
Location: Borneo Island
Posts: 2,450
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 906 Post(s)
Liked: 150
Is there any bad effect if I cover my DIY basstrap / first reflection absorber with a layer of paper before I cover it with fabric?
Skylinestar is offline  
post #11444 of 11453 Old 08-09-2016, 10:21 PM
AVS Special Member
 
climber07's Avatar
 
Join Date: Sep 2010
Location: SoCal
Posts: 2,099
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 317 Post(s)
Liked: 1324
Quote:
Originally Posted by Skylinestar View Post
Is there any bad effect if I cover my DIY basstrap / first reflection absorber with a layer of paper before I cover it with fabric?
Air is the audio medium. Air must be able to pass through a material for absorption to work. Paper will reflect the sound and act as a transducer.
climber07 is online now  
post #11445 of 11453 Old 08-10-2016, 04:36 AM
AVS Special Member
 
HopefulFred's Avatar
 
Join Date: Mar 2007
Location: Atlanta, GA
Posts: 3,554
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked: 405
It is true that the paper will reflect some of the signal, but that's probably not a problem. Any bass or even midrange signal has so much energy that the paper will not have enough mass to reflect it. Only high frequency sounds can be reflected by paper. The effect of that will likely be that the audible portion of the reflection acts to broaden the acoustic image from the front soundstage. If you are in a mixing environment - not a home theater - the focus of the soundstage is probably very important, and you should avoid the paper. In a home theater, it's mostly a matter of preference.
climber07 likes this.
HopefulFred is offline  
post #11446 of 11453 Old 08-10-2016, 10:25 PM
AVS Special Member
 
Skylinestar's Avatar
 
Join Date: Jun 2008
Location: Borneo Island
Posts: 2,450
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 906 Post(s)
Liked: 150
Quote:
Originally Posted by HopefulFred View Post
It is true that the paper will reflect some of the signal, but that's probably not a problem. Any bass or even midrange signal has so much energy that the paper will not have enough mass to reflect it. Only high frequency sounds can be reflected by paper. The effect of that will likely be that the audible portion of the reflection acts to broaden the acoustic image from the front soundstage. If you are in a mixing environment - not a home theater - the focus of the soundstage is probably very important, and you should avoid the paper. In a home theater, it's mostly a matter of preference.
Thanks.
So double wrapping the Roxul batts with fabric is still a better way to prevent the fibers from leaking out?
With a single layer of fabric, the fibers can sometimes "poke through", pricking my fingers when I hold it.
Skylinestar is offline  
post #11447 of 11453 Old 08-11-2016, 09:14 AM
AVS Special Member
 
HopefulFred's Avatar
 
Join Date: Mar 2007
Location: Atlanta, GA
Posts: 3,554
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked: 405
If paper seems too reflective for your taste, two layers of fabric may be the best choice - I can't speak to the effectiveness in terms of managing the fibers. You might also consider a very thin plastic film, like cling wrap. The lighter and thinner the membrane, the less significant its effect.
HopefulFred is offline  
post #11448 of 11453 Old 08-11-2016, 05:52 PM
Advanced Member
 
dnoonie's Avatar
 
Join Date: Jan 2014
Location: Seattle, WA area
Posts: 799
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 232 Post(s)
Liked: 187
Quote:
Originally Posted by HopefulFred View Post
If paper seems too reflective for your taste, two layers of fabric may be the best choice - I can't speak to the effectiveness in terms of managing the fibers. You might also consider a very thin plastic film, like cling wrap. The lighter and thinner the membrane, the less significant its effect.
I like the idea of 2 layers of fabric. I'd be afraid of plastic or paper rattling. A layer of inexpensive acoustic transparent fabric, then your fabric of choice over that. I haven't concerned myself with it, most of my panels came with rockwool and only one layer of fabric, I've not been bothered when handling the panels, but then it could be the acoustic fabric that was used so your experience could be different.

Cheers,
dnoonie is offline  
post #11449 of 11453 Old 08-11-2016, 05:55 PM
Member
 
hobsocc7's Avatar
 
Join Date: Apr 2012
Posts: 173
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 61 Post(s)
Liked: 39
Can you use web adhesive? When I picked up the linacoustic from the HVAC place they said to buy that for the edges to prevent fibers for becoming airborne

Sent from my Nexus 6P using Tapatalk
hobsocc7 is offline  
post #11450 of 11453 Old 08-16-2016, 04:59 AM
AVS Special Member
 
Skylinestar's Avatar
 
Join Date: Jun 2008
Location: Borneo Island
Posts: 2,450
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 906 Post(s)
Liked: 150
I have a question regarding placement of bass traps. All guides say bass trapping is best done at boundaries & corners. In the example of this diagram, how thick should the wall material be to be considered as boundary & corner? If a house wall is made of a layer of thin wooden panel, does that equates to not having a wall at wall, hence bass trapping not required? If you were to place some bass traps, do you place it at the corners of that brick wall? or the corners of the dry wall? or the corners of the thinner walls?
Attached Thumbnails
Click image for larger version

Name:	boundary.jpg
Views:	36
Size:	47.1 KB
ID:	1604713  
Skylinestar is offline  
post #11451 of 11453 Old 08-16-2016, 08:19 AM
Advanced Member
 
jeff43's Avatar
 
Join Date: Nov 1999
Location: Hemlock NY
Posts: 518
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 148 Post(s)
Liked: 79
I have a 22' x 11.5' room, 7' ceilings with one short wall being the stairs leading to the basement. 22' wall is the TV wall.

Atmos set up with Atmos front speakers (yes, I know, ceiling height issue). Center surround speakers hung from ceiling, rear surround ear level on wall, seating 8' from screen. Center channel above screen. Two sub's.

Plan on curtain that can be pulled to cover stair area while using system.

Obviously, this setup will be far from perfect but this is what I'm working with.

My plan is 4 wedge bass traps in TV wall corners (ceiling, floor), area rug to fill most of room, all walls: hard surface (wainscoting) 3' high and cork top 4' of wall. TV wall will also have shelving on both sides as TV will be built into the wall as well. Ceiling will be dry wall.

All I want to do is to reduce the "boominess" of the bass and reduce the reflective "hollow" sound if I can without dulling the whole room.

My question is for the top 4' of the walls: is cork okay or should I do carpet panels or just leave the dry wall alone? Again, I'm not looking for perfection, just trying to reduce bass muddiness and mid range reflections with reasonable treatments. I just want to ensure I'm not missing something really obvious.

Thanks.
jeff43 is offline  
post #11452 of 11453 Old Yesterday, 06:34 PM
Member
 
genesis_avs's Avatar
 
Join Date: Oct 2004
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 11
Quote:
Originally Posted by HopefulFred View Post
It is true that the paper will reflect some of the signal, but that's probably not a problem. Any bass or even midrange signal has so much energy that the paper will not have enough mass to reflect it. Only high frequency sounds can be reflected by paper. The effect of that will likely be that the audible portion of the reflection acts to broaden the acoustic image from the front soundstage. If you are in a mixing environment - not a home theater - the focus of the soundstage is probably very important, and you should avoid the paper. In a home theater, it's mostly a matter of preference.
Using this logic/information, could you just use normal (non-AT) fabric to cover the panels and get the same results acoustically? Seems like it would be a win-win-win: save money by using less expensive fabric, reflect or diffuse the high frequencies to broaden image, and absorb the midrange. Am I missing something?

Last edited by genesis_avs; Yesterday at 07:07 PM. Reason: spelling
genesis_avs is offline  
post #11453 of 11453 Old Today, 06:01 AM
AVS Special Member
 
HopefulFred's Avatar
 
Join Date: Mar 2007
Location: Atlanta, GA
Posts: 3,554
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked: 405
I am unaware of any errors in your logic, but as with all things it will depend on your particular situation and goals. I'm not in a position to say.
HopefulFred is offline  
Sponsored Links
Advertisement
 
Reply Dedicated Theater Design & Construction

Tags
Fv15hp Subwoofer , Denon , Audyssey



Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off