My Super Chunk

[Rednose]

Here are some pix of my Super Chunk I built last weekend.
Used 703, Burlap, liquid nails and sprayed it with fire ******ent spray when I was finished.
Feel free to comment and thanks for looking!

[Glenn Kuras]

thumbsupthumbsupthumbsup


Great job!!

Glenn

[Black Bottle]

Your super chunk looks great! I'm in the process of treating my room. Did notice a difference in the sound of your room? Also, which brand of fire ******ant spray did you use? Would you recommend it?

[Rednose]

Thanks for the kind words!
Here is a link to the Flamex spray.
Flame ******ant, paint, coatings, fireproofing, fire ******ant, flame ******ant

FlameX PF for natural products. I used burlap, then I got a sprayer from Ace hardware. I would recomend it, but I would recomend getting burlap thats allready treated. You can order it online.
The spray is a bit messy but if you allready have treatment up, theres not much of a choice. It doesn't stain too bad, unless it drips on a dark colored wall.

I would say the room sounds tighter and clearer for sure!
I mainly did it for cosmetic reasons. I had someone measure out the corners and we put in the 1"/1". It was an eyesore for about 6 months.

[hduncan]

Does this triangular design work better than a rectangular one that lets the air behind the trap to absorb from both sides??

[Glenn Kuras]

Originally Posted by DarkEcho

Does this triangular design work better than a rectangular one that lets the air behind the trap to absorb from both sides??

Yes on the lower frequencies.

Glenn

[hduncan]

So, for higher frequencies with shorter wave lengths, its best to open the back to catch more of them.. But to catch the lows you need thicker mass.

In theory wouldn't it be better to have a gap behind the superchunk even for low freqs? Its just a lot if real estate.. Right?

[waveterm]

I´m buildning corner absorbers, Superchunks, right now. I´m wondering if you guys did anything to prevent the weight of the insulation to compress the lower layers ?

My corner chunks will be 3 to 4 meters high so the weight will be a factor as more and more material is stacked.

The size of my triangels is 24" x 24" x34".

I´m using mineral wool in the back corners and glassfiber in the front corners. I had the material left over after the main construction was done.

I could use some L shaped metal fixing plates to make "shelves" with. It would allow the insulation to rest on the plates. Maybe put them in every 50cm or so.

Any thoughts/recommendations ?

WT

[vespiz]

I used a fairly light material (Paroc Extra) for my superchunk, so it was actually a good thing that it compressed while stacking. Made it a bit more denser, but didn't really affect my plans by using more material than calculated. Always calculate some extra! You'll find ways to use the "left-overs" somehow.

[DanDan]

This looks really simple but it covers a couple of issues really well.
Corner Traps finally finished! - Home Theater Systems - Electronics and Forum - HomeTheaterShack
It deals with the compression and also provides for mounting the fabric covered frame in front.

DD
Sound Sound - Homepage

[greenears]

Does no one sell superchunk bags? Readyacoustics sells bags that will work for "normal" type bass traps Ready Acoustics, LLC - Afforadble, Durable, and Stylish Acoustic Products - Bass Traps - DIY! Solutions - Mounts - Insulation but it doesn't look like anyone has bags to cover superchunk style trapping?

So if one builds his own superchunks, one would have to resort to covering with fabric as opposed to zipping up in a bag.

[666666]

Originally Posted by DarkEcho

Does this triangular design work better than a rectangular one that lets the air behind the trap to absorb from both sides??

Originally Posted by Glenn Kuras

Yes on the lower frequencies. Glenn

The "super chunk" design as shown above utilizes a lot more 703 than when just hanging flat pieces diagonally across the corner... looks expensive.

How much extra real-world performance are we talking here by packing the entire corner full with 703 as opposed to just hanging a flat section on a diagonal (assuming same frontal area)? Significant performance increase in the low freqs, or just a little, or...? Any data, graphs, etc?

Below what frequency can a gain in absorption be made by packing the corner full of 703?

Thanks

[mikahanau]

Building a "super chunk" like this surely takes a LOT more 703 than just hanging flat pieces diagonally across the corner.

It is not nessesary to use 703 to fill all the space behind a rectengular cornertrap.
Best way to build a superchunk is to use 703 for the front and fill the space behind with the light cheap fluffy stuff.
cheers
Mika

[bumbum]

Originally Posted by mikahanau

It is not nessesary to use 703 to fill all the space behind a rectengular cornertrap.
Best way to build a superchunk is to use 703 for the front and fill the space behind with the light cheap fluffy stuff.
cheers
Mika

WHY ? Does the fluffy stuff do a better job ? is 703 better for broadband ?

[Glenn Kuras]

Originally Posted by bumbum

WHY ? Does the fluffy stuff do a better job ? is 703 better for broadband ?

No, but would cost you less. I still would say though that filling the whole area with 703 would still be a bit better.

Glenn

[mikahanau]

I still would say though that filling the whole area with 703 would still be a bit better.

703 is so dense material, that the soundwave will be reflected if the way through the 703 is to long. So not the whole depth is used.
when you use the fluffy stuff at the back you can use the hole depth, and as said before , you safe some money.
cheers
Mika

[666666]

Originally Posted by mikahanau

703 is so dense material, that the soundwave will be reflected if the way through the 703 is to long...

So, you're saying if we had a giant stack of 703 that was say 6 feet thick, some sound waves would be reflected off it? I wouldn't think this would be so. Perhaps elaborate. Interesting concept.

Regardless, when talking about low frequencies, I have to question whether or not light-duty "low-density" insulation placed BEHIND a straddled 703 bass trap will have much effect over just having an empty cavity. Perhaps in theory it would help, but in terms of "real-world performance", I'd think that it would essentially not make any difference to the end user... thus not worth doing.

However, it makes sense that placing good "dense" material behind the trap might actually help... not necessarily solidly packed... just speculating.

What makes sense to me is that, after a sound wave passes through 4" or 6" of 703 straddled in a corner, will some additional "low-density" material behind it really make a difference over "no-density" (empty cavity)?

Here's an idea... ... place 703 flat against a wall in a corner, then place another 703 panel flat against the adjacent wall in that same corner... and then place 703 diagonally straddling this same corner. What you'd have here is a "triangle" made of 703 with a cavity in the center of the triangle. Gurus, what say you? Sound like a good strategy? I think this might be better than merely straddling the corner and adding only "light-duty" stuff behind it. With a triangle, the sound would first pass through 703, then pass through some air space, then hit 703 again. This method would also use less 703 than packing the space full and thus cost less.

[DanDan]

Does a corner full of 703 work better than a straddle of 703 with pink insulation fill? Nobody knows. How about a 705? Without tests none of us know. IMHO however, experience, intuition, and common sense, are useful when there is nothing else to go on. So.....
If I wanted to save money I would straddle the corner with 705 vs 703 (tests show 705 is better). I would then fill the corner with pink attic insulation, or indeed any old offcuts or fluffy stuff I had lying around. I believe this will improve performance because it increases the depth without increasing the gas flow resistance much. Increased depth improves bass absorption.
This rule only falls down with the very high densities of say 705. 703 is kinda in the middle so I would happily do the full SuperChunk with it.
Regarding the Guru question. Well, Butterfly, the three panels in the corner is bound to be better than a single straddle panel. I suspect however that a 'nested' approch, with say a panel of 705 on the outside, then a panel of 703 behind it would be the best in terms of bang for buck. You will find the three panel corner stuff and I believe some nesting plans also at studiotips - tips on studio design, acoustics, and wiring. This is the home of the StudioTips SuperChunk and it is likely that every variation has been tried and discussed there.
Finally I have done full 34 inch wide Chunks with 48KG Fibre, equivalent to 703. RT at 35 Hz dropped from 900 to 450 mS. An incredible performance, so I doubt if there is a reflection or gas flow problem.

Dan FitzGerald
Sound Sound - Homepage

[Pryzefighter]

Originally Posted by Rednose

Here are some pix of my Super Chunk I built last weekend.
Used 703, Burlap, liquid nails and sprayed it with fire ******ent spray when I was finished.
Feel free to comment and thanks for looking!

thumbsup
Looks great.... I am doing room treatments on a budget. Two kids under 2 and a crap job. Lets just say I am taking notes.

[Sonic_X]

Hey Rednose nice job man! thumbsup
If you don't mind couple questions:

1. where ecxactly did you used liquid nails?
2. why sprayed it with fire ******ent spray, 703 is made of fire proof material.

Thanx
Jay

[Rednose]

Hi Jay, I used liquid nails on the 1"\1"s that were nailed to the wall.
If fact, any thing that can rattle should be liquid glued.
I used fire ******ant spray on the burlap.
Its flammable.

[PeteJames]

What kind of frequencies are these really effective down to? I noticed on Ethan Winers guide he says his traps are effective down to 80 hz - I was thinking bass traps should be helping you out in the 30 - 100 hz range

[DanDan]

I have measured considerable action around 37Hz with three large SSC's in a small concrete room. See the thread Room Analysis Primer V2
DD