Corners - Superchunks or Panels?

[Rednose]

Here are some pix of my guitar booth (its more like a guitar room) getting near completion.
To answer the question of what program I used to sketch it up, it was Google Sketch up.
I made 6 panels in all using 703, birtch 2' - 4' -1/4" panels, and wraped them in burlap. I used Glenn's method for haning them in the corner.
To be honest, I made superchunks before because I'm retarted when it comes to any construction projects.
Glenn's video made it easy to under stand.
I will get some more Flame X and spray them when I get some more $$$ next week.
For the ceiling, I double insulated with R-11 (Two layers) and wraped the large HVAC vents with Duct insulation.
I also ran low of 703 full pieces, so on some of the panels I used 3 leftover pieces and glued them to the backing board.
At this point I just didn't want to buy a whole new supply of 703.
I know its probably not best to make panels this way, but hey, the room sounds great!
There is a little bit of reverb, but thats cool. All my other rooms are dead.
I will post some clips when I get some clients recording in it as soon as possible.
For now, just singing in the room, it just sounds great!
The room cost me several hundred, and thats with using left over 703, and birtch panels I had from left over projects.
It was alot of work, everything in the studio is!
I will get a throw rug to sit under the amps, and I have a GOBO if I have to have two amps in the room at the same time.
Remember, this room will be generally out of site from the clients, so I'm not going to make it that purty.
Thanks for all your input!





In this last pic, you can see the tube I placed through the wall to run cords between the guitar booth and the drum room.

[Glenn Kuras]

Looks great and glad the video helped you.



Glenn

[Rednose]

Originally Posted by Glenn Kuras

Looks great and glad the video helped you.



Glenn

Thanks Glenn!
I'm buying pro panels next time.
This was too much work!
Matt

[Glenn Kuras]

Originally Posted by Rednose

Thanks Glenn!
I'm buying pro panels next time.
This was too much work!
Matt

Look at it this way, you now see the value.

[Lemonsqueezer]

Looks good Rednose. The pics and extra info is helpful to someone like me who will be starting a similar project in the next few weeks.....I'm of to try this Google skectch up thing.

[Rednose]

Originally Posted by Lemonsqueezer

Looks good Rednose. The pics and extra info is helpful to someone like me who will be starting a similar project in the next few weeks.....I'm of to try this Google skectch up thing.

Good luck, and try to get some help!
I hired someone for about 5 hours of time to help hang the R-11, NASTY STUFF, and to wrap the ducts.
I would say the whole room took about 20-25 hours at least.
Matt

[kraskland]

Originally Posted by Lemonsqueezer

Looks good Rednose. The pics and extra info is helpful to someone like me who will be starting a similar project in the next few weeks.....I'm of to try this Google skectch up thing.

Yeah, the pics are great. I love seeing projects detailed like this. thumbsup If you install insulation between the studs, staple the paper backing on the stud edge facing the room rather than inside the cavity. The insulation will perform better when it isn't squished in the corners, at least from a heat insulating perspective. My guess it would be the same for sound. It won't make a huge difference, but every little bit helps.

[DanDan]

Bass RT measurements are a bit of a swamp. However, I agree with Mr. Everest when he said that Acoustics is part Art part Science. I believe intuition, horse-sense, repeated observation, and even anecdotal information are all useful, albeit not ultimately provable.
Regarding the comparitive performance of SuperChunk vs Straddle Panel.
I have a room which was treated extensively with Panels in the Corners.
Most surfaces were concrete so not surprisingly there were remaining audible problems. The octave band containing the lowest axial mode (35 Hz ) was broadly speaking 800-1000 mS long, depending on where you measured. Three of the Corners were filled with 34 inch Superchunks, 8ft ceiling. 48kG Fibreglass. The same Octave band, measured in the same way (mic locations marked on the floor) had shortened to 500-700mS.
This was a pleasant surprise. I did not expect to find a measureable effect at 35 Hz given the wavelength. I won't be writing a White paper on this as my methods and documentation of the process would not stand up. I offer it here only in the absence of something more rigorous.

Best, DD

[Glenn Kuras]

Originally Posted by DanDan

Bass RT measurements are a bit of a swamp. However, I agree with Mr. Everest when he said that Acoustics is part Art part Science. I believe intuition, horse-sense, repeated observation, and even anecdotal information are all useful, albeit not ultimately provable.
Regarding the comparitive performance of SuperChunk vs Straddle Panel.
I have a room which was treated extensively with Panels in the Corners.
Most surfaces were concrete so not surprisingly there were remaining audible problems. The octave band containing the lowest axial mode (35 Hz ) was broadly speaking 800-1000 mS long, depending on where you measured. Three of the Corners were filled with 34 inch Superchunks, 8ft ceiling. 48kG Fibreglass. The same Octave band, measured in the same way (mic locations marked on the floor) had shortened to 500-700mS.
This was a pleasant surprise. I did not expect to find a measureable effect at 35 Hz given the wavelength. I won't be writing a White paper on this as my methods and documentation of the process would not stand up. I offer it here only in the absence of something more rigorous.

Best, DD

ROCK!!!!!

[cojo67]

Originally Posted by jwl

Matt, glad to hear things went well. Fiberglass/rockwool is definitely nasty stuff to work with....

So my question is about this Superchunk fiber glass being difficult to work withand nasty stuff, can you cover the chunk up with some type of plastic wraps before you put it in the corners and place fabric over it WITHOUT affecting it's ability to do it's job correctly? The other reason that I ask is that they would be easier to move one day if I move my studio if the "chunks" were wrapped up in "4 linear foot" pieces as well.

[Weasel9992]

Originally Posted by cojo67

So my question is about this Superchunk fiber glass being difficult to work withand nasty stuff, can you cover the chunk up with some type of plastic wraps before you put it in the corners and place fabric over it WITHOUT affecting it's ability to do it's job correctly? The other reason that I ask is that they would be easier to move one day if I move my studio if the "chunks" were wrapped up in "4 linear foot" pieces as well.

Putting a layer of thin plastic wrap on the front is fine. Don't wrap the panel in plastic...that will negatively effect its absorption characteristics.

Frank

[DanDan]

You can clad your fibreglass in Polyester Wadding. This is cheap and makes life a lot easier. Fibreglass is indeed nasty, but very likely not at all as dangerous as you might think.
The Comparative Safety of Rockwool, Fiberglass, and Organic Fibers (a review)

DD
Sound Sound - Homepage

[cojo67]

Dan dan, Frank, thanks as always for the info.

[weitbrecht79]

Originally Posted by Glenn Kuras

In all of my testing I have found that when filling the corner 3 to 4 pound will work best. BUT with that said if you have 6 to 8 pound on hand that will work.

Glenn

one question about the density / material thing: Is there any difference between a 4 pound rockwool and a 4 pound fiberglass?
I mean - these are absolute values, right? So the acoustic value of both should be the same - or not??
It's just because I'm confused about these posts that say, if you're going to use rockwool, go for a higher density (6 to 8 pounds), since I can't see a remarkable difference between the two materials (given same density and thickness) on the absorption coefficient site of bobgolds.com
Or is there anything I haven't figured out at all....?

[Lemonsqueezer]

Density is not what determines absorption co-efficiency. The flow resistivity is the fundamental determining factor. This is measured in rayls. Unfortunately you will have a hard time finding these measurements for materials. So its more of an educated guess.

[Glenn Kuras]

Density is not what determines absorption co-efficiency. The flow resistivity is the fundamental determining factor.

I do agree but when something is thinner the higher density will absorb more low end.

Glenn

[weitbrecht79]

OK, I got that.
But generally (or just if someone has found out by trying), does this mean, a rockwool of 4pounds (unfortunately i can classify it only by this unit) is less effective than a fiberglass of 4pounds?
i am about to make some superchunks for my control room and i am just wondering if there will be a significant difference in performance between these two materials.

[Glenn Kuras]

i am about to make some superchunks for my control room and i am just wondering if there will be a significant difference in performance between these two materials.

Not really, both preform about the same. Just buy by price.

Glenn

[weitbrecht79]

So - just to make sure i really got the point - density is not the right unit to describe absorptive quality, but spotting flow resistivity (the correct unit) is quite difficult.

BUT there is no significant difference in performance between rockwool and fiberglass anyway (meaning they have more or less the same resistivity), so superchunks made of 50kg/m3 rockwool (sorry about the wrong unit again...) will be within the ideal range, correct?

But i still wonder if there is no correlation between density and flow resistivity...

[Lemonsqueezer]

Originally Posted by weitbrecht79

So - just to make sure i really got the point - density is not the right unit to describe absorptive quality, but spotting flow resistivity (the correct unit) is quite difficult.

Density does have some bearing, but is not absolute. But as the flow resistivity is rarely quoted for these materials density becomes our best guide.

Originally Posted by weitbrecht79

BUT there is no significant difference in performance between rockwool and fiberglass anyway (meaning they have more or less the same resistivity), so superchunks made of 50kg/m3 rockwool (sorry about the wrong unit again...) will be within the ideal range, correct?

Generally rockwool / mineralwool/ fibreglass can be treated as roughly equal.

I would say 50kg/m3 is perfectly fine for superchunks. I am not convinced that a higher density would yield that much performance gain for a superchunk.

[Glenn Kuras]

I would say 50kg/m3 is perfectly fine for superchunks. I am not convinced that a higher density would yield that much performance gain for a superchunk.

I agree also. thumbsup

[weitbrecht79]

OK - that's good to know...

I got another question..
There are two corners in my room which are limited from one side (window..).
A convenient way would be making the chunks asymmetrical, with 45cm on one side and 62,5cm on the other side (that's because the panels themselves are that size).
You think that's a reasonable size for superchunks or is that too small?