Room treatments behind furniture?

[JTC]

Would putting proper room treatment panels behind things such as large sideboards or cabinets be a waste of time, or is it worth doing? This is assuming, of course, that one had spare treatment panels that otherwise couldn't go anywhere else in a room. The same question applies to underneath or behind sofas I think.

 

[Purité Audio]

Depends upon the frequency of the bass waves you are trying to absorb, a 60Hz bass wave has a length of thirty odd feet, depending on various factors you need to absorb a quarter of the length of that wave!
Keith.

 

[Rodney gold]

If the cabinet / sofas are backed up to a wall , relatively useless. Anything occluding the panels will reduce their effectivity big time.

 

[IanW]

Some of my Helmhotz absorbers were under the sofa but are now behind the sofa and behind the cutains. Mine are tuned to absorb around 64 Hz, measurements show they work, as do listening to the effect on music or on test tones. They aren't 15 foot long!

Keith, I agree the absorbing tube needs to be a quarter wavelength, but I don't end up with 15 foot as that length? I will check later but am at work having a few minutes break at present.

Ian

 

[JTC]

I was thinking along the lines of mids and up. Basically, my wife has a lot of pictures that she wants on show, and which currently take up the space where wall-mounted panels would go. My daft idea was that perhaps these pictures could be mounted on top of the wall panels (e.g. GIK 244). Similarly for a flat screen TV; we've currently got a 40" but are toying with the idea of a bigger screen (maybe 50") and I wondered if it could be wall mounted on top of a pair of panels and what the reduction in effectiveness of those panels would be...

As I said, probably a daft idea but at the moment I am feeling around for what might work.

 

[Rodney gold]

I made these "picture" panels for my room. You can combine pictures with panels
HF/Mid panels HAVE to be exposed

 

[Purité Audio]

Some of my Helmhotz absorbers were under the sofa but are now behind the sofa and behind the cutains. Mine are tuned to absorb around 64 Hz, measurements show they work, as do listening to the effect on music or on test tones. They aren't 15 foot long!

Keith, I agree the absorbing tube needs to be a quarter wavelength, but I don't end up with 15 foot as that length? I will check later but am at work having a few minutes break at present.

Ian

Ian typo sorry it should have read twenty odd feet,but still a lot of foam, Helmholtz resonators work in a different way.
Keith.

 

[AndyU]

Maybe the 100s ask too much of your room - why not try some 50s? Might also make the mrs happier than taking up even more room space with panels and traps. The other day you were wanting to tame a 30Hz issue - now you're talking about soaking up mids and up - what's changed?

 

[JTC]

Nothing at all. Mids are fine. This is nothing to do with fixing a problem, so much as making the most of what I have. The big hump at 30Hz really doesn't seem to intrude, but it may be that judicious treatment may bring significant improvements, and I am looking at all the options. Don't want to drop to 50s, I like my 100s

 

[AndyU]

50s wouldn't necessarily be a drop, for the same reason that 150s wouldn't necessarily be an improvement.

Still confused about what you're trying to do. Two posts ago you said you were "thinking along the lines of mids and up.". In your next post you say "mids are fine", but you're trying to improve the 30Hz issue you've detected. You aren't going to have any effect on that by putting a bit of foam behind a tv, for sure.

P.S. Here is an interesting thread on gearslutz about 100s, rooms and room treatments. Notice how to get nice behaviour in a room bigger than yours one studio used 12 feet deep traps.

 

[JTC]

What I'm primarily trying to do was to tame that bass hump, but as it's so deep down, and in light of a bit more reading, I want to try to reduce the decay times a bit. Now, I have the chance of a full GIK kit at a discount price, but this has more panels than I can use, hence wondering whether I can press some of the surplus into use behind furniture.

 

[Obi1]

Try it, or sell them on if it doesnt work. There seam to be loads of people getting interested in this stuff now, so I belive its not going to be hard to sell the ones you dont have a use for.

 

[IanW]

What GIK panels are these? There are Helmholtz panels which will help smooth the decay response. But if they are just sheets of foam to absorb the bass, then as Keith has pointed out, they will need to be at least 5 foot thick, and they will absorb frequencies above that so they have the potential to make the room sound odd!

You need tuning that is targeted to the problem frequencies, not a very wideband approach.

But if you could buy the panels cheaply (and sell them for a similar amount if they do not work) then you could see what effect they have on the room as that would be an interesting an experiment.

 

[muzzer]

JTC
You appear to be burying your head in the sand, people have been telling you for months that the 100's are to big for your room.
Stop faffing around and accept defeat.

 

[JTC]

Nah, the 100s are just fine. I'm 95% happy with them, and just seeking the final 5% or at least 2-3%... my room isn't *that* small - 18'x16'x11'-ish - although my wife might argue that the speakers are a bit imposing. I mean, I *could* sell them and go back to my active Adams (which I still have), but, hey, they sound spectacular at 95%....

Anyway, there are others with 100s in smaller rooms, so

 

[Cereal Killer]

100's are perfect for a room that size. I'd even be tempted to use them in a smaller room!! Have you compromise positioning by becoming domestic challenged though? And have you tried a different front end, since bass is you primary concern this could be a solution too!!??