Question? Ceilings and dry walls..

[CoolCat]

So i read the posts and saw the pic's (pics worth a 1000 ideas)
Also looked at John's corner and front/back drawings..nice but probably a little much for what i'm doing with the wooden spaced panels. the wife didn't like the grass sod idea either so.....

Q1)
i read square rooms suck especially with flat ceilings.
i saw several control rooms with like an angled ceiling/wall over the main desk.
SoMm's and a few others had this.

is this angled wall intentionally built up to eliminate a flat ceiling negative effect?

Q2)
noticed wall coverings to be drywall/nothing, blankets, drapes, "egg foam and other molded-foam" (most common), and the more serious control rooms with the gap-wood-pro design.

of the above mentioned- any recomendo's?
is a full wall of covering better than squares spaced out?
are corners the worst area needing to be treated first?

infojiveshtcraptalknancyreagandolebanana:

looking to improve a "songwriter/demo type room", one room.
(won't be having a vocal booth/control room thing)
recently learned i need to use speakers and not headphones..why my mixes sound awesome in my studio-cans and mud everywhere else!!...so its monitor and room acoustic time.

room~14L x 10w, 8ft ceiling (you know with that nasty popcorn sht that falls in your eyes when you touch it)...blank canvas.

Guitars,Bass,Keys, Vocal and Drum machine, monitors- standard.
I do have a typical type studio desk, a store display type model.

 

[Michael Jones]

I didn't understand a lot of this, but i'll try to help.

Q1)
i read square rooms suck especially with flat ceilings.
i saw several control rooms with like an angled ceiling/wall over the main desk.
SoMm's and a few others had this.

is this angled wall intentionally built up to eliminate a flat ceiling negative effect?

It's no so much that "square rooms suck" as it is the modal response of a square room sucks. It has to do with parallel walls, the way sound waves bounce around those walls, and the time it takes for the reverberation of a sound to die off.

Square rooms aren't impossible, but they are infinately more difficult to deal with when considering problem frequency attenuation.

So in an ideal world, square rooms, or more appropiately, parallel walls, are avoided.

Q2)
noticed wall coverings to be drywall/nothing, blankets, drapes, "egg foam and other molded-foam" (most common), and the more serious control rooms with the gap-wood-pro design. ?

I think what you're asking is that you have seen acoustic treatments range from nothing to "wood-gap-pro design" and which is best?

Again, this comes back to the modal response of your room.
With the dimensions of a room, certian computer programs allow you to predict the modal responses that can be approximated for that room. This identifies the most problematic frequencies.
Types of acoustic treatments can vary dependent on the frequencies you're trying to attenuate.

That in and of itself is a topic on which volumes have been written!
I'd say look to the SAE site, and study up a bit more.

Take notes here in class too!

 

[CoolCat]

Re: Re: Question? Ceilings and dry walls..

certian computer programs allow you to predict the modal responses that can be approximated for that room. This identifies the most problematic frequencies.

That in and of itself is a topic on which volumes have been written!
I'd say look to the SAE site, and study up a bit more.

Take notes here in class too! [/B][/QUOTE]

I know the Pro studio setup is better....i'm not that far out there

but skeptical on the foam $$$....i guess.
Is it reeeeally better than a "comforter/moving blanket"?
Does Guitar Center, Corner wedges for $15 for 2' really work as a BASS TRAP?

I have zero expieirence other than reading and ears.

computer sounds interesting, but I'm just doing a small room, like 14X12 thing....musican-workstation very simliar to Giganova's if you saw that first pic on her thread.





just trying not to waste $$$ and Time.
thanks again.

 

[CoolCat]

12x14 workstation studio

see if the attachment works:
maybe get some more inputs here......

so going from the drywall of sound.
i did the comforters thing...small difference, better than nothing?

this weekend, placed a King mattress upright against the rear wall, up 14" from the floor...sound change was noticeable..so encouraged to move forward.

still a comforter in the front/ behind the monitors...nothing in the corners or ceiling.

 

[knightfly]

Attachment didn't seem to work -

Are you concerned with sound getting in/out, or only sound quality?

What's your general location, so we can suggest sources of material?

Approximate budget?

And yes, ANYTHING you put in or take out of your room will change things, some more noticeable than others. The foam stuff SORTA works, but there's LOTS better things for less if you're willing to track them down and do a bit of DIY.

If you can answer the above questions, we should be able to help you decide what/how/where to do... Steve

 

[CoolCat]

startin' from scratch

I just measured the room 13x13 with 8ft ceiling.easy.
attachment problems.

Knightfly you asked??
?Sound in/out:
it'd be nice to minimize (second prioirty). i don't have noise IN issues. sometimes noise out..says the wife!

?Sound quality: (first prioirty)
I'm up for DIY, and am buying the house so I can do wht the hel i need to do. one positive, i got saws and tools and a ruler!
Goal: is a decent mixing room (and listening!)

looks like sht.(but thats third prioirty and is a prioirty)

my "hurry up" instinct is saying go buy the foam. but will it be more like the blankets?
very tempting as its at GC and WalMart.

thinking of sound panels too? any info on this..how to build?
the move-ability may be nice.

budget: shoestring...$20 here $40 there.

...all inputs/ideas are welcome.
thanks

i keep hearing RIGID FIBERGLASS?...I won't be itching will I?

 

[CoolCat]

been reading

Michael and Knightfly,

thanks for the links.
a lot of info. for me to read.
interesting. +

from averaging the sample of articles:
I'll save time and money from No Foam, no eggcartons...

SMALL ROOMS= Absorbtion=Rigid Fiberglass

Now i just need to figure out specific trap dimensions for a 13x13 ,with 8'ceiling, room.

and start buying the rigid fiberglass panels...

 

[CoolCat]

Acoustics & Limited Budgets/MIX magzine

Acoustics on a Limited Budget

BY EDDIE CILETTI

Mix, Jun 1, 2002
A rigid, flat surface is sonically reflective across the spectrum; bare walls in the front of the control room should be avoided, because high frequencies can bounce around. You want only direct sound from the monitors to reach the engineer's position. Sculpted foam, carpet, curtains or covered Fiberglass will tame the early reflections that can mess up the stereo image. Behind the engineer's position, diffusion via irregular surfaces like bookshelves, rough stone or an “engineered” diffuser can do the trick. An acoustician can diagnose some aspects of a room fairly quickly and tell you where to put this stuff.

The most simple panel designs can be thought of as floating walls; they take the punch so that the wall behind doesn't have to, minimizing the amount of energy to hit the wall and obstructing any reflection back into the primary listening area. A broadband absorber is a simple solution that can be effective from high frequencies down to 125 Hz, depending on panel size and distance from the wall. Low frequencies below 125 Hz require specially designed resonators or bass traps to absorb the larger waves.

<< I placed the King Mattress at the rear. It sounded good too, I think i understand better why it works?1)plenty of mass 2)plenty of air space internal-absorbtion 3) about 4" from the wall -floating wall effect.
.....looks like sht tho! horrifc cosmetics...but cheap$

Almost any acoustic treatment will absorb high to mid-frequencies when mounted directly on the wall. As frequency drops, however, not only must panel size and density be increased, but space must be added between it and the wall. At this point, many acousticians prefer Type 703 Rigid Fiberglass insulation for its density; it is commonly available in thicknesses from 1 inch to 6 inches.
<<<sounds like some cheap foam won't hurt and may take some of the treblies out of the room & 703 for serious bass trapping

 

[mmistudent]

you don't want any parallel surfaces. Even if your cieling is gently slanted and hard to notice, it will help alot. Standing waves are your enemy. Try not to have any 90 degree corners... low frequencies tend to build up in corners. Again, no paralell walls. If your room is a cube and you can't do anything about it be prepared to drop some serious coin on bass traps and acoustic foam.

 

[CoolCat]

been studying up...but???????

Does a small 13x13 room need more than one bass trap???

So many articles pointing to the-
Owen Corning 703- Density 3 (Low freq absorbtion co-efficient 125hz/ .62) and .70 NRC...see I'm sounding like an Engineer now.
Now I'm getting why you gearheads kept saying 703 only...

703 $8.16 a panel FRK style. 2' x 4' x 2" .

WHY NOT 701???
Interesting because I almost bought some 701, at .45cents a panel!!NRC was better at .90 no FRK!!!
....but learning the specs...the 701 2" was 1.5 Density and only .22 at 125hz...lightbulb is starting to flicker!

703 was triple the absorbtion at lower bass freq's...per the OC specs, and tho i am a spec skeptic, i'll take the gangs word for it on the 703.

 

[Todzilla]

a small room needs more help with bass traps than a big room. Small rooms don't have the dimensions to allow a bass wave to fully develop. So you have more phase problems with bass in a small room. I heard that you need as many as eight bass traps in a small room, but for a big room, you can get away with as few as eight. Haha.

For a room your size, you're best off trying to kill all reverberation and cancel all room effect, since it's pretty unflattering.

The best way to do this is with high density fiberglass, such as Owens-Corning 703. Sheets of this stuff, wrapped in breathable fabric and mounted a couple inches away from your wall will go a long way to eliminating your room effect. This works far better than sonex stuff, plus it's a lot cheaper. Sonex does absorb nearly as low in the frequency spectrum as OC703.

The wood gap designs you see are probably not applicable for a small space. They are best suited for a large space, where you can afford to tailor some abatement for a specific frequency range. Your space probably requires a broader approach.

Good Luck!

 

[CoolCat]

703

thanks...excellent input there Todzilla!

i found some 703 and will try to zip out today and start purchasing a 8 sheets.
i don't know about cheap? these are like $8 a 2x4x 2"!

also when you say 8 traps, are you refering to 8 panels or 8 corner type bass traps?

I was planning on starting in the rear corners- bass trap 1. from floor to ceiling (2pcs. 703)

or would i place the first traps in the front corners by the monitors?

when my favorite Pro CD's start sounding great in this room, i'll be happy and when i place another sheet up and don't hear a big difference i'll move on. thats the plan, man...can you dig it!

 

[Michael Jones]

Re: 703

when my favorite Pro CD's start sounding great in this room, i'll be happy and when i place another sheet up and don't hear a big difference i'll move on. thats the plan, man...can you dig it!

Well, nothing can subsitute a good pair of ears, but the methodology you propose is basically trial and error.

Theres a better way to go about it.
I ran the modal response of your room, and your problem frequencies occur at the 200Hz-600Hz range. Not surprising.
So what you want is an acoustic treatment that will attenuate those frequencies.
Perhaps a panel absorber, or variable panel absorber would be the ticket here.

http://www.saecollege.de/reference_material/pages/Low Frequencies.htm

And a helmholtz resonator set in the corners could tame those mid level frequencies.

http://www.saecollege.de/reference_material/pages/Low Mid Frequencies.htm

 

[Todzilla]

Re: 703

thanks...excellent input there Todzilla!

i found some 703 and will try to zip out today and start purchasing a 8 sheets.
i don't know about cheap? these are like $8 a 2x4x 2"!

I know that doesn't sound cheap. Still, in terms of absorption for the buck, that's as good as it gets. Compare to Sonex for real value

also when you say 8 traps, are you refering to 8 panels or 8 corner type bass traps?

Either. Corner traps are the easiest to make, since they don't require airtightness. Panel traps are more complicated and involve some carpentry skills, but they generally absorb much lower than corner traps. I've done both at my studio, see http://www.toddejones.com/hugebuilding.html The idea behind my "universal 8" comment was that smaller rooms need more abatement.

I was planning on starting in the rear corners- bass trap 1. from floor to ceiling (2pcs. 703)

That will help. Thicker is better, too. You could either double up the thickness, as I did to obtain 4" thick, or you could stuff the void with regular batt insulation, sans facing

or would i place the first traps in the front corners by the monitors?

Probably won't matter a whole lot which you do first. All four corners will help a lot. Another place to consider is corners where walls meet ceilings. Other than the difficulty of defying gravity, this is a great place to trap bass. It's just as efficient as wall/wall corners, but doesn't eat away at precious real estate of floorspace.

when my favorite Pro CD's start sounding great in this room, i'll be happy and when i place another sheet up and don't hear a big difference i'll move on. thats the plan, man...can you dig it!

Oh yeah..... Mine is under construction, but when I hit my thumb with a hammer, you should hear the lucious purity of my string of cursewords, so sonically balanced...

 

[CoolCat]

703 acoustics

thanks both for the inputs....greatly appreciated!
huge help & interesting.....step by step pics were encouraging...and the calculations and link lead me to...

I'll build one or two "airtight" bass trap for the 200-600hz,
per the chart i'm getting 3/16" plywood and 2" space...(plywood on the front?!!, strange)
2qty. 703.

the rest, panels 2" from wall. 6qty.

still a little gray on best positioning ceiling, front walls, rear,corners...

as someone stated, it probably doesn't matter in this small of a room as the sound is bouncing around so much...anywhere will help.

 

[Todzilla]

For full information about panel traps, see the definitive text: http://www.ethanwiner.com/basstrap.html
There are important tips to follow which will ensure your carpentry is not all for naught. Especially:

1) Don't neglect the airtightness. If it's 99% airtight, it might as well be 0%

2) Make sure the panel won't touch the insulation within. It must vibrate freely.

For slat style (Helmholz Resonators), see http://www.johnlsayers.com/HR/index1.htm I think these units are best when you want to address a specific low end problem frequency. The precision of the slat width, depth, spacing cannot be overemphasized.

...and I concur with Michael's input as well. He probably has better input regarding the slat style traps.

 

[CoolCat]

oops!

Todzilla,thanks again,
i didn't catch the #2...keep the panel free...i was all set to attach it to the plywood!doh!per the slayers link.

its Friday...hopefully it'll be a productive weekend.

i'm not going to attempt the slat type this 'round tho it'd be great...just going for some basic's and a couple "airtight" 200-600 range traps.

i kinda wished they had the material faced 703 easily availble like on your link. it didn't appear to be too much$ more.

 

[CoolCat]

in progress..absorber panels for 13x13 ??

Front Wall:
completed 3qty. 703, cloth faced absorber panels per the drawings from the links. thanks again.
(2qty mid-bass= wall-1"air/703 2"/1" air/ cloth front)
(1qty upper-bass= wall/ 703 2"/ 1" air/ cloth front)
also added 2qty Foam-Eggshell pads 2'x2' squares for the Hi-Mid Freq ranges. I'm collecting these from the shipping garabge as I can...hey its free!

REAR WALL:
Wall-2" air/ King size mattress upright/ 1" air/ comforter (7ftx6ft)

pretty fhkn cool project so far.
the cloth fronts were a pain...

any inputs on which wall to place the next plywood faced/bass traps? I have 4qty. 703's left.

 

[CoolCat]

BASS trap transfer..

Will the corner bass trap cause more bass/vibration to go to the next room?

Todzilla...must have looked at your pics 100 times..really helped.


i'm re-reading this info...and its the corners to do first...
fhkme...i did the front wall thing lost focus.
....corners.

i was standing on a corner once.

 

[CoolCat]

traps...can you dig it..

so far so good.

ceiling clouds next...