mineral wool behind a painting?

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phantom power
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mineral wool behind a painting?

Post by phantom power »

I've got a large-ish oil on canvas painting that my fiance painted and I'd like to put it up in my small recording/practice space (11x13). Since it's a small space, I don't want to leave such a large area (where the painting would go) untreated.

I've got some 4" roxul that I'd like to just put behind the painting. I know that I'll lose a lot of the higher frequency absorption, but will it still give me some help in the low end? Is this just a bad idea in general?

Thanks in advance.
-AE
xSpace
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Re: mineral wool behind a painting?

Post by xSpace »

Why will you lose high frequency absorption and what have you done up to this point...besides hanging pictures on the walls...and I must ask, how many pictures have you hung already in an attempt to...what is it you are trying to do?



Please read the forum RULES (stickies) that can be found at this link:
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Then make certain that this is reviewed:
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Please correct your initial post to conform with these rules and guidelines. Many here will not only NOT help while waiting in respect for owners and other better qualified persons to proceed, but will simply ignore these type of posts completely.

You may want to immediately ask "what is it that I have missed". Most often it is as simple as including your geographical location in your profile. It might be that you have not included your budget!

Trust me in that the more you know the better others can help you and that the answer to that question is in the forum rules linked page.


Until then, good luck,


Brien
phantom power
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Re: mineral wool behind a painting?

Post by phantom power »

:oops: Okay... edited my profile to include my location as well as a few other things.

In a nutshell:

I'm just wondering if having the roxul behind the painting will compromise any of the low frequency absorption. As far as the high frequencies go, I assume that the painting being in front of the mineral wool will reflect a good amount of the higher stuff.

Thanks
-AE
xSpace
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Re: mineral wool behind a painting?

Post by xSpace »

Small rooms, like bed rooms, need very specific acoustical treatment. Specific and verifiable using this web site forum. The cookie cutter set is low frequency corner absorption (owens corning 703 type), best application being the Super Chunk, a reflection free zone and hard floors/ soft ceilings.

"compromise any of the low frequency absorption" Don't know what you have that can be compromised.
The room dimensions aren't of any length to allow bass frequencies to fully develop, so the compromise doesn't exist, based on the very little I know about this room.

One picture that reflects the highs and has potential to subdue bass frequencies in a small part of a wall is not an acoustical solution.

Get better information and ask better questions with way more detail then you just did, but make certain your lover knows it is no reflection on their work...it is what it is :)
phantom power
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Re: mineral wool behind a painting?

Post by phantom power »

Actually, with all due respect, I'm not asking for an acoustical solution for my room (yet). I'm only asking about this one particular piece.

I do have a 2'x4'x4" cloud (made with the same Roxul) over my drums, and five 2'x4'x2" panels (made of OC703) on my walls. I realize that this not enough to be an acoustical solution for my little room. As the funds become available, I will be adding a lot more.

For now, I'd like to put up a painting that I like. Rather than having such a big part of my wall space (about 4'x5') be just a cool piece of art, I'd like to put some 4" thick Roxul that I have laying around behind it.

My question is this:
Will the Roxul actually be able to do it's job with a painting in front of it or will the painting be so reflective that it would be like the Roxul wasn't even there?

Thanks again for your replies.
-AE
Speedskater
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Re: mineral wool behind a painting?

Post by Speedskater »

xSpace wrote:Why will you lose high frequency absorption and what have you done up to this point...besides hanging pictures on the walls...and I must ask, how many pictures have you hung already in an attempt to...what is it you are trying to do?
Until then, good luck,
Brien
Because an "oil painting" does not have the same acoustic properties as an acoustically transparent fabric like GOM.
I have read the some of the commercial panels with artwork don't have great acoustic properties.
Kevin
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Re: mineral wool behind a painting?

Post by Soundman2020 »

I don't think that it is possible to answer that question accurately, since the acoustic properties of your painting are unknown. Basically, you are on your own, being your own guinea pig, any time you do something outside of the "tried and tested" category. That said, I doubt that the painted canvas will affect very low frequencies too much, and very likely will reflect very high frequencies, but the actual properties are not known, so nobody can really say. Will the canvas perhaps act like a membrane resonator? Or will it just act more like a reflector? Hard to say...
xSpace
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Re: mineral wool behind a painting?

Post by xSpace »

Speedskater wrote:
xSpace wrote:Why will you lose high frequency absorption and what have you done up to this point...besides hanging pictures on the walls...and I must ask, how many pictures have you hung already in an attempt to...what is it you are trying to do?
Until then, good luck,
Brien
Because an "oil painting" does not have the same acoustic properties as an acoustically transparent fabric like GOM.
I have read the some of the commercial panels with artwork don't have great acoustic properties.

Thank you SpeedSkater but it wasn't a question as much as it was a request for more information on what had been attempted up to this point.

As each of us know, one piece of a puzzle has little to do with a rooms acoustics. And as Stuart said, we just do not know anything about this room, with a painting on the wall, to be able to say anything.

I wouldn't hesistate to say to the OP. go for it. It will do two things. Reflect highs and hotspot some lows.

Where is the fun in that? I want an even listening environment, in the live room or control room or the theater or the speaking room :)
Dave Carrranza
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Re: mineral wool behind a painting?

Post by Dave Carrranza »

I have a related question.

I am looking to treat a cement ceiling with steel beams with cement coating, the ceiling is a roof so there are not sound concerns from above. The room I am treating is a rhombus shaped room with a 45x20 foot dimension, specifically this room is our live room where we record drums.

As of now we have installed a floor that sits on auralex rubber u-joints, with a 2x4 substrate filled with ATI acoustic Rockwool (stuffed). This has eliminated the high mid echo from the cement from the floor but we still have ceiling to contend with.

The ceiling consists of a series of beams that intersect with larger steel beams coated in cement. The main beam has a lot of flutter echo issues that we are going to address by hanging sound gobos and diffusers in that area. As for the main areas of the ceiling I was thinking about using some large scale canvas that I have an backing them with ATI rock wool.

The canvas are a 78x78, and two 58x78 flat texture painting with heavy oil paint saturation. Note this is not acrylic, they do not dry the same… oil paint does not have the same hardness as acrylic or latex. My plan was to deepen their frames and fill it with 4 inches of rock wool with a fabric covering the back to keep the guts of the large gobo in. Was planning on hanging it by chains from the ceiling creating an angles pattern from the ceiling by adjusting the lengths of the chains to create a geometric pattern for diffusing the sound.

My main goal on this is to diffuse the issues caused by the cement ceiling. Would these methods be effective or am I just putting too much thought in incorporating these large format painting into the studio?
Soundman2020
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Re: mineral wool behind a painting?

Post by Soundman2020 »

Hi Dave. Please check the announcement at the top of the forum about posting. You seem to be missing something! :)
You can find the announcement here(click here). Actually, several people, who are experts on this forum, will most likely not reply if you don't do what is written in that post.

Anyway, once again, since there is no research on the acoustic properties of painted canvas (or at least, none that I'm aware of) there really isn't much anyone can say about that. Painted canvas will reflect some portion of highs, and be invisible to some portion of lows, but the exact effect is not know.

Regarding your treatment: the drum riser you made is a good start, and will be keeping impact noise out of the structure, which is good, as well as probably damping the room a bit, but as you noticed, isn't doing anything for the ceiling. The general rule for acoustics is that you want "hard opposite soft". In other words, with a hard floor such as cement or wood (which is a good ideas acoustically), you want a "soft" ceiling, which means large areas of deep absorption. 4" of mineral wool of about 48 kg/m3 density is also a good start.
that we are going to address by hanging sound gobos and diffusers in that area.
What you describe aren't really "gobos", but rather "clouds". You didn't say how high your ceiling is, but it most likely isn't high enough to be able to use most kinds of diffuser. Diffusers need space to work evenly. Many meters...

So you need clouds up there, not gobos or diffusers. A cloud is just a large frame filled with acoustically absorbent stuff, hung from the ceiling, often at an angle, so you have the right idea with your "paintings filed with mineral wool". The issue is the painting: normally clouds are covered with acoustically transparent cloth of some sort, but painted canvas is not acoustically transparent at all, except at some mid and low frequencies. That may or may not be what you need for your room, but most likely not.
My main goal on this is to diffuse the issues caused by the cement ceiling.
Once again, diffusion on ceilings is seldom a good idea, unless you have really high ceilings. Most types of diffuser (especially QRD types) create lobing patterns around them, that need lots of space to even out and blend together again. There normally isn't enough space between the ceiling and your head for that to happen, except with very high ceilings. Most home studio control rooms are even too small to use diffusion on the walls effectively (but that doesn't stop many not-so-well-informed folks from doing it anyway, just because the saw diffusers in a pro-studio somewhere, and thought that they looked cool... :) ). So unless your ceiling is at least 4m above your head, I wouldn't be thinking of diffusion up there. On the other hand, since your room is decently large at 45 feet long, you could use diffusion on the end walls, if you wanted to...

Have you actually measured the response of your room, to see where the issues really are? If not, then download REW and do the tests, then post the results here.

That's a nice sized room: you should be able to get it sounding great for drums, if you treat it right.


- Stuart -
michellelynnart
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Re: mineral wool behind a painting?

Post by michellelynnart »

Yes, I very much agree with you, and best of luck for your prints. I am also an artist and I have a canvas art prints shop. I am providing the well-framed canvas art prints that are painted by myself. People can use it to spice up walls with wall art.
DanDan
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Re: mineral wool behind a painting?

Post by DanDan »

Absolutely insert fibre behind paintings. Also thin materials will kill the most audible aspect of flutter echo. But I am dubious about how a beam might suffer from it, or how it might get stimulated up there. Does it?
Waka
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Re: mineral wool behind a painting?

Post by Waka »

You may not have noticed the spammer had resurrected this ancient thread DanDan :D.

I imagine he got it sorted out by now :lol:

Dan
Stay up at night reading books on acoustics and studio design, learn Sketchup, bang your head against a wall, redesign your studio 15 times, curse the gods of HVAC silencers and door seals .... or hire a studio designer.
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