My dimensions are complex -- diagram on this page: https://systems.audiogon.com/systems/9064
I have no side reflection points to worry about but I have a low ceiling. I have a concrete floor but it has both wall to wall carpet, thin, and area rugs on top of that. Bookshelves line the back wall and I've arranged the books to help diffuse. Front wall is brick.
Let me just stress that I'm not asking for advice (yet) about how to fix my room, but rather experiments to try.
Curious to know how much if any of this the people offering advice above have actually done?
These are the same panels, only mine are 1" thick. https://www.theanalogdept.com/c_miller.htm This was a long time ago. 2004 according to the fellow who took the pictures. This was just where the panels happened to be at that time. They are not like that now. https://systems.audiogon.com/systems/8367
You don't need no measurements and in fact unless you really know what you're doing are probably about as likely to make things worse as better. Your ears are all you really need. Because, think about it, if you do something per measurement and it sounds worse are you going to force yourself to live with it because, measurement? Or are you going to go by what sounds best? Your call. Think about it.
Especially since if you look at the absorption specs for your panels (OC has a spec sheet) you will see they really only work at midrange and treble. Which you can easily hear. So have no need for measurement anyway.
Simply experiment with your panels just like I did. They are light enough to be held temporarily with simple pins. That is how mine were. You can try full panels but they cut easily by hand with a razor blade or knife. One simple test is to stand different places in the room and clap. Listen for the decay. It should be smooth and even. If you hear flutter echo then you know to treat one or both parallel walls in that area.
Two reflections that tend to be worst for smearing imaging are the side and front walls. On the sides there is the first side wall reflection where the left speaker bounces off the left wall, and there is also another one where the right speaker bounces off the left wall. Also you might want to check out the Decware site where he has a very interesting analysis that explains why corner treatment as I have done is so effective.
Keep in mind that at this point you already have more than enough material to do your whole room. More than enough. All you need now is to figure out where it goes, and then find some nice fabric to wrap it in.
Fabric needs to be as acoustically transparent as possible, or it will actually reflect and not allow the OC703 material to do its thing.
Thank you all. I've done the mirror test and have no sidewall first reflection points that are closer than 15 feet. My listening seat is about 8 feet from the speakers.
I mainly want to listen. I am doing measurements, too, in order to see if I can establish correlations between the graph and what I hear. Naturally, the decisive element is to go by what I hear, but so far doing measurements has guided some changes in my room that sound better. So, for me at least, measurements are helping.
Here’s a 1st report: 6 OC 703 panels placed at various places.
(a) Placed on first reflection on floor, immediately under ceiling reflection spots. Had noticeable reduction of harsh upper mids and treble. Even better on some tracks with two panels.
(b) Placed along front wall between speakers, mostly, four panels. Vocal tracks which were already located in the center became much more focused. E.g. When before I was listening to “a singer” in front of me, now I was hearing the vocals from “a singer’s head.” So much better localization.
(c) Placed on rear wall -- which is a bookcase with books pulled out at various degrees -- there was very little change I could hear.
So far so good. Didn’t try to measure, just listened.
This is going to be uncomfortable. Starting at your feet, wrap the Corning insulation round and round your body, slowly working your way up. It's best to lay down for this procedure, and don't forget to wear a mask. Also, it is very important to set your CD player to 'repeat', as the best that you can do after completing the procedure, is to set with you back up against the couch and listen. One last note: It is a good idea to take several doses of Benadryl about 20 minutes before starting this wonderful experiment.
If you end up with extra, two other uses to consider are
“Let me just stress that I’m not asking for advice (yet) about how to fix my room, but rather experiments to try.”
it’s your room and you are the one that has to play around with placement. it can be fun / interesting to hear how the sound changes while moving panels around.
really surprised as much as you are on the forums that you don’t have the equipment on anything (isolation).
I bought several from www.readyacoustics.com. years ago.
In my small room, I now use only two (doubled @ 4" thick that I modified with several holes @different sizes) directly behind my speakers with the tweeter in aligned at the center of the panels.
It's easy to overdamp with these.
I believe Ready Acoustics will sell you coverings?
@mitch2 — thanks for those tips. I probably will want to use these for something more than room pads, because like many, I'm not so handy that I will be able to finish these into something long-term good looking.
@tvad Good suggestion. I hadn't thought of subtracting and then adding back in. That would create a mix of diffusion and absorption I don't have there now.
@riley804 I have read about isolation a lot, but, first, my stuff was on a really solid and low coffee table and then I moved it off to the side. I figured I would sort out the room before the isolation. The speaker stands are new and very solid. Perhaps you'd do isolation first?
@slaw Thanks for the reference. I'll check into coverings. I really need to see if my 20hz - 300hz range is dialed in before doing too much more with the upper frequencies (using my OC 703); so that's why I call what I'm doing now just "playing."
@hilde45 looking at the drawing of your room, have you thought about making some changes? have or can you put the stereo where the bed is and then you could put the couch where the door of the bed is and the bed could go where the couch or stereo was? with the stereo where the bed is, you would have side walls and if you had panels left over could put them on stands and have them behind the couch.
just a thought......
@edunbar and @tazz2 Thanks -- I will go take a look. I've watched a lot of videos about acoustics and treatments but perhaps there will be something additional here to learn.
@corelli I'll consider suspending the panels. Once a 2" panel is suspended down 4" from a 6'5" ceiling, it is now at about 5' 11 inches from the ground and just about low enough for someone to bump with their head. But I think that this is at least a temporary experiment that will bear fruit. And maybe even an 1" off the ceiling would be good.
@slaw 2 inch spacers sounds like the easier way to get corelli's suggestion implemented. Thanks.
@optimize Thanks for the suggestion. I've played test tones and walked around the room your suggestion about the panels in a sack is interesting. I'll try that. I'll just thank you now, if that's ok.
@riley804 I have not tried the stereo where the bed is (in this room, it's impossible) but I have tried putting the stereo at the opposite end of the room, in other words, on the short wall. It is not as good. Still, I have not tried it with treatments. That's a good experiment.
Hello all. I worked for Owens Corning for over 13 years and supported, from a technical side of the business, commercial boards etc... that 703 is a part of. First off, insulation will not kill you, breathing in insulation may be a slight irritant to some people but for most it is fine. Yes wrap the panels, insulation is ugly on the wall.
Remember first what you are trying to accomplish in a room. There are several ways sound can affect acoustics in a room and there are several ways to control it. Diffusers, blockers, baffles, Insulation will help with reverberation in the room by absorbing it. There is an actual science to it and too much absorptive material (700 series fiberglas in this case) can be bad, too little can be bad. The best way to narrow it down is to calculate the amount of reverberation in a room and then calculate the amount of material you need to absorb the appropriate amount of reverberation. Thickness of the panel matters as well because thicker material will absorb lower frequencies better than thinner material. I can go on and on... but think about what you are trying to accomplish and choose the right material for the job.
The use of your panels on front wall behind speakers and possibly between and at reflection points on ceiling and floor between speakers and listening position are great places to start.
You might consider framing your panels with 1" x 2" pine. Back with cardboard. Cover with burlap type material of choice. Look into making your own bass traps for corners.
@jetjuice Thank you for your replies. It's a privilege to have someone with your experience taking up my question. I'm trying to calculate the amount of reverb with REW.
And at this point, I'm playing with the material -- to see how it affects what I hear and what I measure.
FWIW, I don't expect to be able to become an expert by messing around with a few panels, but I expect to get some experiential insight into how the room can change. (Sort of like the way we try lamps in different parts of a room, with different bulbs, and then stand back and see how it looks, or sit down and try to read, etc.)
@vermonster -- Good suggestion. I'll try some doubled up layers, especially after I play some test tones to identify where the bass is really piling up in standing waves.
@mesch Thanks for the building material suggestions! I definitely need a project!
IMHO, the foundation for a great room begins with managing the bass as pointed out above, the most difficult and the most expensive. Start here.
"....My question is: What are some useful experiments to do with the panels and where in the measurements might I see some changes? ..,"
I don't see, with all of the advice given, where anyone has stressed the need to examine the corners. That is the first place that I would start with. Others have already given good advice for ceiling and walls, but suggest that you ignore the guy who wanted you to wrap yourself in fiber glass. Good luck.
@bigwave Thanks so much. Bass is primarily what I have been measuring in my room. Moving speakers, listening position, the sub, doing the sub crawl, etc. But this chart looks very handy and may have some ideas I've missed.
@assetmgrsc I've definitely been interested in corners and will give them a hard look. Yeah, and no fiberglass Santa suit for this grinch.
In looking at your room diagram, I was wondering if you notice any sort of channel dominance or time alignment/phase issues being made from the right wall: I think the bathroom is along that wall. I ask because of how close and oddly comprised that wall, and area are verses the left side (from couch position). I would think you would be hearing or experiencing some different characteristics from the right verses left channel. I have a slightly similar issue in my listening space, only drastically more profound.
One test I did to measure and see how dramatic the difference was, I played a simple instrument tone from violin or any stringed instrument. I disconnected one channel/speaker and documented sound qualities, characteristics, feeling, essence, issues. Then swapped and did same with other speaker only, and did same process. It was amazing how different the sound was coming from each speaker because of the asymmetrical distance to walls. Granted to be noted this would change again when both were playing (phase, cancellation, other time delays, smearing, etc) but this gave me a very accurate and dramatic test to at least find ways to contend with my one odd wall due to distance from speaker to it, verses the other and it's vastly more open air.
I would wonder if going dramatic with this test, and then use all the panels along that bathroom wall to just hear if and what difference there was to just know/have as reference.
I think your and other members thoughts on the ceiling are spot on!
Behind the speakers I want to remember would help with focus and again, smearing/blending.
Best of luck. Any room acoustic improvements produce vastly greater impact on your listening experiences than anything.
Sorry I did not read all the above suggestions so the may be a duplication. I too bought a dozen pack of the exact same material,
assembled a frame and wrapped with a soft fabric color keyed to the wall colors. The immediate improvement was dramatic.
Positions to try: Ceiling reflection spots between speaker & seating.
As you have no side reflections that eliminates the 1st ones otherwise needed. If there is a wall behind you add a couple there.
Same for the area between the speakers. Glass surfaces are bad and benefit from attention as well. How many you need will in total will depend on the amount of existing absorption material in the room. You have carpet so that is very good.
Smart question. Good luck!
@amtprod It’s a good question, but what is not evident from the diagram is that the right speaker, nearest the bathroom wall, actually fires into the entrance way which forms part of the front wall. In other words, there is no first reflection point (as revealed by the mirror test) on that wall.
I went and measured differences in the room. In actuality, my right speaker is 12’6" from the right wall and my left speaker is 15’ 3" from the left wall. I’m not sure that the difference there (3’3") is enough to cause a big difference. Both are far enough way to not be able to smear the direct speaker sound reaching my ear from about 8 feet away.
I will try your test. Yesterday, I did put my panels along that bathroom wall just to see what changed, and there was no apparent difference. Again, because there is no first reflection point there, so that is probably the reason.
Hey @hilde45, good post ... the first report-post shows that you have identified two symptomatic areas in the mid to high frequency range.
As another experiment you could double-up panels (2 x thick etc. gives double the bandwidth, roughly) and extend absorption lower.
The ceiling should be a deep panel (example 5 inch depth), with long narrow panels-spaced at different lengths apart to gain a baffle effect.
400 - 4000 wavelength range (3 feet - 3 inches) will likely need the most attention other than bass.
A Tube Trap(ASC) would go a long way to tame bass and help with mid to high frequency.
+++ re acousticfields yourube videos.
I've only been learning this stuff from the videos and from reading, so grain of salt..
It's easy(ier) to affect high frequencies than problematic bass, so I would start with the bass traps and getting that under control. By the time you're done with that, you may need less of the high frequency absorbption. If done the other way around, you may do too much of the high frequency absorbption. That is just my guess.
The reason for mounting the panels with a space behind them is to make them more efficient. This was mostly for the big bass traps, corner bass traps, that were made for maximum effectiveness because we can never really get enough efficiency at the very low bass notes. You may not even absirb enough with just the 703's. So the diy'er would make a 24 inch wide triangular trap from floor to ceiling and it would be a good idea to have a 1 inch gap to the wall to add even more to its efficiency rating. So it became the norm when giving advise. But if you don't have the ceiling height and you may not even need that particular frequency to be affected, then you may only need the 2 inch or even a 1 inch panel. That's why you are measuring.
Best of luck
Thanks, cissado. Bass first -- got it.
Here's a brutal response I got from Acoustic Fields when I described my room (and the 6.5 foot ceilings): "This is the worse ceiling height I have seen in 20 years. Please find another room."
Sigh. Well, at least I enjoy listening to music in that room, whatever he says.
I don't see, with all of the advice given, where anyone has stressed the need to examine the corners.
Also you might want to check out the Decware site where he has a very interesting analysis that explains why corner treatment as I have done is so effective.Only the one comment and the two web page links.
Probably everyone else missed it too.
Well, Foley says the corners aren't necessarily the spots to be in. He's done thousands of rooms and his data does not support that. He's mentioned it numerous times in his videos. Of course everyone can have their own opinion.
I suggest watching a few of his videos. He does focus mostly on bass frequencies imo. Maybe because they're the hardest to fix.
Concentrate on below Schroeder frequency where the room is in control above it's the speaker that controls.
When I moved I to my current home 8 years ago I asked Dennis Foley about my proposed basement room, which has a low ceiling. He didn’t recommend it at all, and I took his advice and found a different room.
I understand if there absolutely is no other alternative, but reacting emotionally to free advice from an expert doesn’t seem wise.
cissado, Miller -- I heard the advice about corners. I did a bunch of SPL measurements. In my room, corners don't have much bass; it's the front wall behind the speakers that's really overloaded.
Thanks djones. I'll look that Schroeder stuff over.
edunbar Oh, I'm not reacting emotionally. I understand his advice and others have told me, too. I cannot move the room for a few years because we have a family and will do a renovation at some point but I'm stuck where I am. There are many elements of this room that are pluses and it already sounds quite good. So, while I understand the kernel of the advice is sound, it was offered without knowing any of the details of my situation. My sense is that someone at that company (I don't know if it was Dennis who replied) figures they have all the business they can handle! That's fine. GIK and I are talking, and I want to see about Real Traps, too.
I’ve spent the last 4 + years turning my dinning room into an enclosed soundproof highly accurate and articulate dedicated listening room. My room allows for an absolutely stunning listening experience! I have extensive experience with Acoustic Fields bass management technology. I hand-built all 40 of my activated carbon bass absorption panels based largely on Dennis Foley’s designs. I also built a front wall/ inner- wall diaphragmatic carbon absorption system in the room....down to the studs design. My room design and configuration is based on a blend of ideas from Acoustic Fields, Chris Huston and Dr. Earl Geddes. My room design uses diffusion + absorption. The reason I say this is because it took me hundreds of hours and probably thousands of dollars to learn what works well and what doesn’t, before I ended up with my current room layout. I hope to share with you and others some of what I’ve learned as you work to improve your listening experience. I understand that you’re unable to make significant changes to your listen environment, but hopefully I can add something useful to this discussion.
With little understanding and lots of determination, I started my journey over 4 years ago buying 20 panels from GIK as well as absorber products from other online retailers. I started by adding floor to ceiling 12’ thick corner (limp mass) bass traps. I used front wall & ceiling bass traps and absorption panels from GIK and even built several different types myself. I hung dozens of panels from my ceiling and walls. I could go on and on about all the limp mass absorption products I cycled through in my search for small room greatness. I’ve built and rebuilt my room five times over. Each time learning, listening, adding and removing as I go. I was fed up with all the effort and still my room lacked in everyway. My room is small 13x16x9. Pretty average small room. Bass was a major issue. Room modes, bass issues, mid frequency issues, echo, flat/ dull, lacked dynamics..... compressed lifeless sound. But I can tell you this, with the proper use of material and placement anyone (even in a small room) can have a world class music room. With regards to your question about best use of Owen’s 703 bats and where you might see changes....I hate to say it, but a handful of fiberglass bats alone will not provide any meaningful bass absorption. Don’t spend time or money on room corners. Limp mass absorption panels will provide some attenuation of room echo and reverberation. Simply place a few bats on sides walls, a few on the front wall and maybe one or two on the ceiling and see if you notice an improvement, that’s it. Listen for better instrumental placement in the sound image, is there a little more accuracy, if so, the 703 panels are working. Again, bass won’t change much if any. Try this, when standing in your room, clap your hands, do you hear a slap echo between two apposing flat surfaces, if yes, place a panel one each side to kill the echo. An airgap between the wall and panel provides little improvement. (remember this, small rooms usually need more absorption, big rooms usually need more diffusion. Both is best).
Some improvement is always nice. There isn’t anything that can be done to change your ceiling height, it is what it is. Enjoy your room, make a few easy changes if possible to improve your listening experience. If you really want to take your room to the next level, be read for big room modifications.
A link to my room/ system. Hopefully link woks.
(shalommorgan’s listen room)
That's an inspiring effort and a beautiful setup you have. Thank you so much for sharing that, along with your advice. I just spend an hour or so moving things around and so my side walls became my front and rear wall. Terrible -- lots more bass problems and harsh highs. I'm going back to listening across the room width - I have no side reflection issues that way.
I'll take your advice about not expecting too much with a few panels. I do realize that a large amount of a room needs coverage and that my ceilings pose an ineliminable problem. I'm experimenting to learn, but your room now shines out as an ideal!