Porous Absorber Calculator problem and SSC Facing question

[sys40198]

I had this posted in the newbies section and someone suggested I repost the questions here:
Hello people,
I dl the Porous Absorber Calculator and I can't get it to work with excel 2011 for mac! Apparently the new excel for mac does not come with the Analysis Toolpak (wack right?) and i cant find it anywhere online. I was wondering if anyone found a way around this problem or knows a way i can still use this.

I'm also just starting to do some acoustic treatment for my room (10'x10.75'x10.42'...almost a cube...crappy but my rear has a 4.5' foot "hallway" that extends about 4' 8" to the door) and decided to start off with some SSC bass traps (the insulation is 24 in at the hypotenuse). I got one all built (got a pic) with the frames and realized i could see through the fabric . But I went to the hardware store the other day and saw this wall panel that is around 2mm thick and has a white melamine face on what i think is particle board or mdf (not sure tho...material isnt super rigid). Im just curious if i could use this as my face and ditch the frame all together (its held in front of the insulation by velcro). The face would be approximately 1/2 in infront of the insulation. Im sort of doing it like how the pics below show (not my pics but I copied this technique)

I know it'll reflect the high and maybe the mid frequencies, but i thinkin' I can probably take care of those later on with porous absorbers at reflection points. Don't know for sure how it would affect the low end tho (thinkin...hoping it'll be fine tho). I've heard of people putting plastic sheeting in front of their bass traps. I dont really intend this as a resonating membrane...but i'm worried that they might. would they resonate if i don't seal them air tight, or if I could fill that 1/2 in gap with more insulation?

I'm mainly considering this b/c or aesthetics and ease of instalment/construction. It would be awesome cuz it would match my walls (it would look like part of the wall) perfectly and save me sometime and $ (i'm a student..poor) on my other corner bass traps. I think Melamine is fire resitant also and plus i dont have to worry about my dog's hair getting trapped on the fabric.
Would this work? Or is it too good to be true and actually mess everything up.
P.S. I would love to test this and do a frequency sweep of my room...but my interface crapped out on me about a month ago and I still need to buy another one (waiting for tax returns hehe)
Any help would be much appreciated, Thanks!

 

[jhbrandt]

Nice traps. You can use melamine for facing like that and they will work fine for LF. The panels will resonate if there is no damping. How about using the melamine for the bottom section only. You are still going to need more trapping in that room. I recommend buying a ceiling tile grid and drop the ceiling down to 8' & fill half the space above the grid with attic blanket - making your ceiling a large trap. Use the compressed fiberglass ceiling tiles, turn them over and cover the fiberglass with fabric. - Use them upside down with the plastic towards the ceiling.

Next, build panels for first reflection points on the side walls and Back wall directly behind the mix position. More info on my publications page along with calculators to help with placement, etc. More good articles can be found on the RealTraps site and GIK site.

Cheers,
John

 

[sys40198]

Thanks for the reply John and your calculators that work on my comp!!. I like ur website btw, especially that "voo-doo sites" page. honestly that blew my mind. It made me curious though, if those companies actually believe what they are preaching or if they know wuts up. Idk which is worse a company believing the misinformation or the willful exploitation of a culture (audiophiles?) of sorts.

IC how the idea of lowering the celings would be an awesome idea. Unfortunately, i think that is way beyond my construction abilities, and plus my parents own this apartment and are letting me live here while im in school. So i dont think they would be down with me making a new ceiling (i havent even told them Im doing any of this yet...bad i know). But they should be alright as long as it looks good and not tooo extreme.

I was wondering if there is any other solutions that would not be so "invasive". I know u gave me probably the best idea possible. But i was jus curious. Sucks that i cant do any frequency sweeps for now. but any thing helps. I'll probably try the bass traps with the frames and fabric...then once i get a new interface, i'll compare them to the melamine face using a test. Maybe I'll post them if it yeilds any interesting results.
Thanks again for the help