Who reads books anymore?
How about a skyline diffuser? I've been meaning to do one, mainly as a wall sculpture. Most are made from wood but I think I'd use a lightweight material like Styrofoam (the blue or pink, higher density stuff). Get creative with some paint and you have some functional artwork.
T30 is the more modern measurement. It is usually doubled to arrive at T60. T60 is not available in ARTA.
Pano,
how did you hang these panels? They look very nice. I would like to do something similar but hang them on the ceiling of our living room (aka my listening room). Our walls are already spoken for, but the ceiling is wide open for some treatment. Since moving to this house with hardwood flooring, and plaster ceiling/walls, my speakers sound mediocre at best.
I'm trying to imagine how you would hang them cleanly from the ceiling.
thanks
how did you hang these panels? They look very nice. I would like to do something similar but hang them on the ceiling of our living room (aka my listening room). Our walls are already spoken for, but the ceiling is wide open for some treatment. Since moving to this house with hardwood flooring, and plaster ceiling/walls, my speakers sound mediocre at best.
I'm trying to imagine how you would hang them cleanly from the ceiling.
thanks
From the ceiling? That's a tough one. Maybe with eye hooks? They are heavy that's for sure. I had to use the big "OOK" brand hangers - the 100lb version. They don't weigh that much, but they are heavy. The big ones are 40lbs, IIRC. I want to do some smaller ones on the ceiling - will use eye hooks there. My ceiling is plywood.
Ah, if only I had command of a room to do it in!
But I've vetoed some decorative ideas of hers, and paid for it...
Greater percentage perforation, closer to the wall = higher peak absorption frequency. Less perforation, deeper boxes = lower peak.
If you make the things as wedges, deeper at one end than the other, it makes for a broader Q notch, and breaks up standing waves floor/ceiling (if you are attaching them to the ceiling, that is). I have spent many hours drilling holes in panels and polycylindrics to tune them to exactly the frequency that needed notching out – yes, of course with them already attached to the ceiling and me up a ladder, how else can you do the measurements?
With the amount of fibreglass I must have breathed doing that (despite mask) I'm not going to worry about what leaks through the cloth.
If you make the things as wedges, deeper at one end than the other, it makes for a broader Q notch, and breaks up standing waves floor/ceiling (if you are attaching them to the ceiling, that is). I have spent many hours drilling holes in panels and polycylindrics to tune them to exactly the frequency that needed notching out – yes, of course with them already attached to the ceiling and me up a ladder, how else can you do the measurements?
With the amount of fibreglass I must have breathed doing that (despite mask) I'm not going to worry about what leaks through the cloth.
For sure! I know how you feel. Having been an apartment dweller most of my life, I never thought I'd have a dedicated listening room. It's a wonderful luxury.
My Listening Room.
But having a room that you can do anything in is not such a big challenge, right? What if you are like most audionutz and have to use the livingroom, den or lounge? What can you do to make it better sounding and still acceptable looking?
Maybe we need a thread, forum or wiki on stealth ways to improve room acoustics. Ways that won't upset SWMBO too much (or just enough). I've always managed to plant big speakers in the living room and won't take no for an answer. But acoustic treatments? No way.
Good to know, thanks! Got any rules that might lead to specific frequency ranges? I'd love to be able to target certain ranges. The only info I remember seeing was for the same size holes, but more or less depth. Seemed more fiberglass just absorbed more of that frequency range.
I'll have to dig out my Master Handbook of Acoustics to see what it says.
I did a quick web wander and came back with this:- PANEL ABSORBER FREQUENCY FORMULA
The formula for determining the frequency of a simple panel absorber is as follows:
F =170/MD
F = the frequency you're aiming to absorb
M = the mass of the panel in lbs per square foot
D = the depth of the air space in inches.
The metric equivalent of this
equation is:
F=60/MD
where the mass is in kilograms and the unit of length is metres.
* HELMHOLTZ TRAP FORMULA
You can determine the operating frequency of a Helmholtz trap with the following formula:
R = 200 P/DT
R = resonant frequency,
P = the percentage of perforation (total hole area divided by panel area multiplied by 100)
T = the effective hole depth in inches (thickness of panel plus 0.8 of the hole diameter)
D = the depth of the air space in inches.
Note that it's easy enough to convert this formula into metric, but the numbers are more straightforward if you stick to imperial measurements.
And, nicely built, they are not unattractive at all; quite a high WAF, (Wife acceptance factor) As (for the perforated ones) the rigidity of the front panel is irrelevant you could drill holes in glass sheet, and damp the interior with stuffed toys… no, perhaps not.
(You wonder why I've never married, and spend all my time, working and free, in a recording studio? It's not just the soundproofing)
It used to be (in Great Britain, at least) that the well-stuffed furniture, carpets and drapes meant the average living room was somewhat overdamped and soggy for critical music listening; now, hygiene and a desire for natural light have reversed this trend. Setting windows at angles as we do in studios to avoid HF splash is rarely possible, so adding diffusion? – basically draw the curtains and pretend the rest of the world doesn't exist. And if the speakers must be aimed at windows (unfortunately sometimes unavoidable) take full advantage of the Haas effect and sit as close to the glass as convenient.
The formula for determining the frequency of a simple panel absorber is as follows:
F =170/MD
F = the frequency you're aiming to absorb
M = the mass of the panel in lbs per square foot
D = the depth of the air space in inches.
The metric equivalent of this
equation is:
F=60/MD
where the mass is in kilograms and the unit of length is metres.
* HELMHOLTZ TRAP FORMULA
You can determine the operating frequency of a Helmholtz trap with the following formula:
R = 200 P/DT
R = resonant frequency,
P = the percentage of perforation (total hole area divided by panel area multiplied by 100)
T = the effective hole depth in inches (thickness of panel plus 0.8 of the hole diameter)
D = the depth of the air space in inches.
Note that it's easy enough to convert this formula into metric, but the numbers are more straightforward if you stick to imperial measurements.
And, nicely built, they are not unattractive at all; quite a high WAF, (Wife acceptance factor) As (for the perforated ones) the rigidity of the front panel is irrelevant you could drill holes in glass sheet, and damp the interior with stuffed toys… no, perhaps not.
(You wonder why I've never married, and spend all my time, working and free, in a recording studio? It's not just the soundproofing)
It used to be (in Great Britain, at least) that the well-stuffed furniture, carpets and drapes meant the average living room was somewhat overdamped and soggy for critical music listening; now, hygiene and a desire for natural light have reversed this trend. Setting windows at angles as we do in studios to avoid HF splash is rarely possible, so adding diffusion? – basically draw the curtains and pretend the rest of the world doesn't exist. And if the speakers must be aimed at windows (unfortunately sometimes unavoidable) take full advantage of the Haas effect and sit as close to the glass as convenient.
Excellent idea !
I was looking for room acoustics in DIYAudio, and found posts scattered in differents forums, not very convenient.
A dedicated forum will have a lot of succes, I'm sure.
Your panels are nice and well thougt (acoustics engineering is my job
).For those who dont like the idea of having glass fibers flotting in the air of their rooms, they can use, lamb wool (++), hemp wool, linen wool, recycled cotton (+), they're also very effectives used this way.
Merci Zptepi! (I used to live in Langedoc myself, very nice region).
Since I made the panels many women have commented favorably on them, much to my surprise and delight.
There will be some new sections in diyAudio, but not room treatment, IIRC. I should push for that, thanks for the reminder.
Since I made the panels many women have commented favorably on them, much to my surprise and delight.
There will be some new sections in diyAudio, but not room treatment, IIRC. I should push for that, thanks for the reminder.
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