Need help w/ acoustic treatment layout please.

[GCR]

Hello All...

I have another thread floating around here about building a studio from a prefab barn, but things have changed...

As it happens, we're buying a new house and the current owner is also a musician and had a rehearsal studio built out back.

That's a great bonus, and saves me some construction...

The sound isolation end of things is solid. It's obvious he did his research and the construction was done right.. very little sound bleed through or into the space.... It has it's own Heat, Air, & Electric.

However, there is no acoustical treatment going on in the inside.
laminated wood floors, gyp. board walls & ceiling.
I've done tons of reading, but I'm still having trouble figuring out just how much of what I need.
How much absorption (sf), How much resonance (sf), how much Bass Trap (sf), etc...

Is there a general rule or calculation where if I have:
(x)Amount Of Surface Area (Reflective)
Then
(x)% Should Be Diffusion
(x)% Should Be Absorption
(x)% Should Be Resonance
Etc...

Now, I know many people tend to lean toward splayed walls, but being the space is smaller and is already complete, I won't be changing the main construction, but I'm not opposed to making some type of movable/hingable slat resonators or the like.

However, I'm thinking most of the Acoustic Treatment will be handled w/ panels, bass traps, slot resonators, or products from a company like Auralex.

This will be used primarily as a rehearsal studio that has the ability to record, but I would like to be able to get descent recording quality out of it.

At the core of the studio will be M-Audio ProjectMix I/O, M-Powered Pro Tool 7.x.x, Assorted Shure & Audix Mics.

Any help, suggestions, direction would be greatly appreciated.

Thank you so much for your help.

Approx. Internal Building Dims.
12'W x 20'L x 11'H

 

[Ethan Winer]

How much absorption (sf), How much resonance (sf), how much Bass Trap (sf), etc...

This is a deep subject, and a complete answer requires far more than will fit into a single reply here. So here's the short version. All rooms need:

* Broadband (not tuned) bass traps straddling as many corners as you can manage, including the wall-ceiling corners. More bass traps on the rear wall behind helps even further. You simply cannot have too much bass trapping. Real bass trapping, that is - thin foam and thin fiberglass don't work to a low enough frequency to be useful.

* Mid/high frequency absorption at the first reflection points on the side walls and ceiling.

* Some additional amount of mid/high absorption and/or diffusion on any large areas of bare parallel surfaces, such as opposing walls or the ceiling if the floor is reflective. Diffusion on the rear wall behind you is also useful in a room as large as yours.

For the complete story see my Acoustics FAQ.

There's a lot of additional non-sales technical information on my company's site - articles, videos, test tones and other downloads - linked under my name below.

--Ethan

 

[GCR]

This is a deep subject, and a complete answer requires far more than will fit into a single reply here. So here's the short version. All rooms need:...

--Ethan

Ethan,

Thank you so much for replying to my post personally and for your insight which I absolutely respect. I've read many of your articles and personally prefer your approach to room acoustics as opposed to splaying all the walls (Which I feel is great waste of space. And for us w/ small studio's, space is at a premium)

I went to the Auralex Site and used they're online room calculator.
(Note: I know you have your own products, and at this point I'm by no means "endorsing" the Auralex Product Line. I'm using any tools I can find to get an Estimate of what I may need to address the rooms acoustics)

By Using their Calculator (Which did not allow for the pitched ceiling condition to be calculated) I input the following information:

12'W x 20L x 11'H = Surface Area 944sq/ft

Their Solution: (1) EPS-168T Kit ELiTE Pro System
(20) 1" B22 ProPanels (2'x2') - @ 80 sq.ft.
(8) 2" CT45s (2'x4') - (Bass Traps) @ 64 sq.ft.
(6) 4" ProFusors (2'x2') - @ 24 sq.ft.

Giving a Coverage 168sq/ft
Room Coverage of 18%
(I would have thought it would need to be higher. Like 25%-50%)


For the novice, as you can well imagine, the amount of information to learn is OVERWHELMING... I like to think I'm a person of above average intelligence, and even with all the information I've been reading over the past months I still feel I've only scratched the surface. (And a little stupid)

Even if the system suggested above was the "perfect solution" I still wouldn't have a clue as to the ideal location for each component.

Many of us (Novice) will probably never fully understand all the science behind acoustical engineering. I don't think we mind spending the money as long as we're assured 1) It Will Work 2) How/Where to properly apply the treatment.

In my specific case, I not so concerned w/ the "Control Room" aspect of the room (Yet)... I want the room to be acoustically correct for a Live Room/Rehearsal Room.

As for the Recording/Monitoring End of things, for the time being I'll use quality headphone for Playback so room acoustics don't have to be addresses from a "Control Room" aspect. In the future I will probably build another room off the Sliding Doors, and make a proper control room and address thats rooms specific needs then.

Is there a company I can send detailed AutoCAD files to and have them run their software to provide Product Information. Amount, Type, & Location.

(I'm An Architect, and have it all drawn up already. As well as have the space modeled in SketchUP)

Ethan, Again thank you so much for your time.

Glen

 

[GCR]

Here' my first go, using the "Suggested" kit... & doing some interior design on the space.

 

[Ethan Winer]

For the novice, as you can well imagine, the amount of information to learn is OVERWHELMING ... Is there a company I can send detailed AutoCAD files to and have them run their software to provide Product Information. Amount, Type, & Location.

This is the crux of it. If you intend to DIY, then you have some homework ahead of you. If you have the budget to buy treatment, then a company like RealTraps will do all the leg work and tell you exactly what to get for that budget. I don't know of any place or service that will do all that work for free. There are acoustic consultants you can pay for this advice, but in the end you'll still need the treatment so (from my perspective) it makes more sense to just buy it from a "full service" place and get both the advice and the products. I hope this doesn't sound like an advertisement, but these are all the options I can think of.

--Ethan

 

[gullfo]

Here' my first go, using the "Suggested" kit... & doing some interior design on the space.

I would put the desk centered and facing the window and the drum kit by the door - add heavy drapes to pull over the window or door as needed for reflection control - probably not often as you don't want a dead room. you can also stagger the treatments to add some efficiency and create more diffusion in the space.

I think given the size of the room and using live drums, you'd want more bass trapping in the corners and possible along the side wall/floor corners. Real Traps also makes a triangular bass trap for the floor and ceiling in the corners. I'd also add a row of the 2x2 on the ceiling. put a cloud over the mix desk and ensure the side walls have the first reflection point treated. if you have the budget, I'd recomend you call Ethan for assistance and product.

 

[GCR]

First, Let me say thank you taking the time to reply and look at my design problem.

(Glenn, I see you answered on both forums... thank you for that. I also see you live in NJ also. Kewl)

Let me also say there is some great ideas here and I'm grateful for the advice.

There a few things I wish to clarify in my design problem & a few question I have based on your ideas...

I went to the Auralex Site and used they're online room calculator.
(Note: I know there are other products, and at this point I'm by no means "endorsing" the Auralex Product Line. I'm using any tools I can find to get an Estimate of what I may need to address the rooms acoustics)

By Using their Calculator (Which did not allow for the pitched ceiling condition to be calculated) I input the following information:

12'W x 20L x 11'H = Surface Area 944sq/ft

Their Solution: (1) EPS-168T Kit ELiTE Pro System
(20) 1" B22 ProPanels (2'x2') - @ 80 sq.ft.
(8) 2" CT45s (2'x4') - (Bass Traps) @ 64 sq.ft.
(6) 4" ProFusors (2'x2') - @ 24 sq.ft.

Giving a Coverage 168sq/ft
Room Coverage of 18%
(I would have thought it would need to be higher. Like 25%-50%)

In my design scheme, I've placed all the absorption on the wall, Bass traps in the corner, and diffusion on the pitch of the ceiling.

That said, the addition of the corner traps, heavy drapes, & offsetting of the panels is a great idea..

However, from a design point I want to ignore the fact that the DAW control center is in the room for now and approach it purely as if the room was a live room/rehearsal room. The reason being, I plan to add a control room off the sliding doors in the Future and will address the specific need of the control room at that time. For the time being, I will use a quality pair of headphones for monitoring.

Glenn, that said, would that change your design solution.

My next question. It sounds as if you would prefer the drums to placed in one corner or the other. Is the ideal? Wouldn't you want to keep symmetry in the space as well as the location of the drum set? Otherwise the soundwaves would hit different walls at different time. Is this ideal for just the sound on the room, or for recording, or both?

Again, thanks for the help and I apologize for my ignorance, but your insight comes appreciated.

 

[gullfo]

overall treatment plan would remain the same. the main difference is that the mix position depends heavily on symmetry (acoustically) and the drum kit would likely fair better without symmetry (adds to scattering and reduces the chance of reinforcing modes etc impact the sound - in most cases you want to move the drum kit around the room until you file the location it sounds best).

 

[bpape]

The plan Glenn drew up looks like a winner to me. I would recommend some additional wall/wall corner control rather than the triangles at the Tri-corner. I'd also go 6" thick on those and on the rear wall directly behind the mix position.

Lastly, if you want a bit more lively sound, you may want to consider some diffusion on the rear half of the side walls instead of one of the absorbers.

Bryan