New space S-Proofing and Acoustic Treatment?

Hi Ethan, Wes, Rod and anyone else who might want to help,

I've finally getting into a new (larger) Space. Basically It's just a 2 car garage. I'm only going to use part of it, though, building a wall to seperate the studio from the rest.

I'm not sure if I should worry to much about sound proofing, beyond doubling up on sheetrock and using lots of caulking. I don't think I could get it to the point of being able to record drums at 2am anyway without breaking the bank.(it gets really quite out here at 2am). During the day it's no big deal. There's enough outside noise to mix with it. Plus the nearest house, besides my own, is about 1/2acre away. I would like to keep outside noise to a minimum in the studio, though. (dogs, cars, lawnmowers, etc.) In this respect, will the Caulking and double sheetrock be ok?

Also, the size of the space is, tentatively, going to be 20x14x8(LxWxH). mixing and tracking will be "same room". Although at opposite ends, I think.

If I were planning to use mini traps to treat the room, how many would I probably need? And, would I need anything else for taming ambience, slap echo, etc.? The floor is a 2ft concrete slab. Would it be better, sonically, to lay down a hardwood (pergo?) floor, or does it matter?

The bottom line is, I'd like to get the space to sound as good as it possibly can.

I hope that covers it. Any help would be greatly appreciated.

Thanks.

[Rod Gervais]

Strider,

I am not ignoring your question - am just tooooooo tired tonight to work through it in my mind - but will be fresh in the morning and will respond then.


:p:

Rod

Sounds good Rod, Thanks.

Something I just thought of-

The roof is actually sloped and the 8ft height would only be if I added sheet rock beneath the rafters, instead of the actuall studs beneath the roofing. If I were to use the actuall roof, the height in the center would be aproximately 18ft and 8ft at each end. I can do it either way, so if one would be better, please let me know. Would this higher/sloped ceiling releave having to heavily treat it as, I assume, would be needed with an 8ft ceiling?

Thanks.

Hi Rod,
I just checked out that Room in a Room Post. What a coincidence!

Does your advice to that member apply to me, too? I'm not building a bedroom, if that makes a difference and, regardless, the space will be built to code.

On another note, I was up late thinking about what I have to work with and where my problems may lie.

I think the biggest thing I have going for me with this project is the 2ft concrete slab that the garage sits on. It seems to me that nothing will be transmitted throught it. It's pretty darn big and solid.

So, with this in mind I thought it may, very well, be feasable to soundproof to the point of being able to track drums at 2am. Maybe It's just inexperience, though.

Anyway, If nothing is transmitted, acoustically, through the concrete, wouldn't that act as a decoupler? I mean if I were to build four walls and a roof which weren't connected to the rest of the garage in any way, besides the concrete slab, the room would be decoupled from the garage. Am I thinking clearly here?

So, based upon that theory, if I built up the walls and ceiling enough, possibly using hat channel to decouple the inner part of the wall from the outer part of the wall, and used multiple layers of dry wall with some form of absorbent between... Maybe this would be enough to stop enough sound from leaking that the rest of the garage would beable to handle what's left.

The problem with the rest of the garage is the garage door. It doesn't have much mass and there are small cracks around the perimeter. A heavy seal and something to absorb, maybe?

Well, I hope you can help.
Thanks

[Ethan Winer]

Mitchell,

> the size of the space is, tentatively, going to be 20x14x8 <

If you make it 20x12x8 you'll have slightly better mode spacing, but of course you'll also lose two feet that you may not want to give up.

> If I were planning to use mini traps to treat the room, how many would I probably need? <

Eight. We have an in-house joke here at RealTraps - whenever someone asks how many they need, the answer is always eight. Large rooms have more surface to cover than small rooms, but they can get away with fewer bass traps proportionaly. So it turns out that eight is about ideal for most rooms. My living room is a little larger at 25 by 15 with an 11 foot ceiling at the peak, and nine MiniTraps was just about perfect. Though I still need to add four pieces of 703 on the side walls and ceiling to avoid the early reflections.

> would I need anything else for taming ambience, slap echo, etc.? <

Yes, probably, and how much depends on your other other furnishings - couches, bookshelves, and so forth.

--Ethan

[Rod Gervais]

Strider,

No it doesn't apply........ sleeping quarters are a seperate issue - although i personally reccomend a 2nd way out of any space - I will not ever be involved with only one way out of a bedroom........

OK - now on to your questions........ higher ceilings are better........ however the "studs below the roofing" you refer to (ceiling joist is the proper term by the way) attach to the wall/roof assembly - and thus are shorts that will pass through your isolation system.

If you have standard framing in your garage - you could always install a beam at the underside of the ridge at the roof peak - and use simpson fasteners to tie this into the rafters.

Then you could remove the ceiling joist (or collar ties if they do not sit on the wall) without creating structural damage to your garage.

You should really have a local engineer go to your house to verify this is ok and to size the beam for you.


The mass of the concrete will help tons with low end transmissions - i don't think i would worry about that - concrete weights about 144 lbs a cubif foot - so you have roughly 288 pcf in floor mass........ :tu:

Ok - on to the question of decoupling - yes and no is the correct answer. If you are talking about being relatively isolated from the outside world - then yes...... but if you are talking about being isolated in the sense of a tracking room to a control room within the space then the answer is no.

You will get some transfer through the floor of low frequency sounds - and the only way i know of to truly stop this is to decouple - and by that i mean 2 seperate slabs with an isolation joint between them. Which i typically break under the wall on the tracking room side.

IN your case - based on what i just re-read (what a dummy i am some times) no difference - the amount of energy you will have transfered to the outside world will make any noise to your neighbors (or vice versa) non-existant.

You can go a long ways towards achieving your goal (and being able to play in the wee hours of the morning - if you do the double wall technique - but do not sheetrock the inner face of the exterior wall...... insulate the heck out of it - and thermafiber would be an excellent choice for that - and the inner wall as well.

Use the exterior stud locations to layout from - placing your interior studs centered on the bay - do not place studs directly inside sutds.

Then insulate the interior wall assembly - install a vapor barrier - then resilient channel (for the truly best wall) and then 2 layers of drywall.

Make certain you do not screw through the RC into a stud during the drywall process...... that creates sound "shorts" through the system.

As far as your garage door goes - why not use that area as sort of an entry/sound lock.. and then a double wall with a double door at the actual entrance to the studio?

That would work well.

Happy Hunting

Rod

Ethan,

Actually, there'll be so much space, compared to the room I use now, I think I could manage with a little less. Plus, that might work well with the Air lock entrance Rod mentioned. If I'm understanding him correctly.

One other question; If I were to make the walls and ceiling unparallel to each other, would that make a noticable difference in acoustics, maybe even negate the need for alot of extra treatment beyond the traps, with the mind that it'll sound better in the end if it needs less treatment to start? Did that make sense?

As far as furnishings...My philosophy is "We standing, we wooking. We no standing, we no wooking". Seriously, though, I probably won't have a whole lotta extra stuff in there. Just the essentials.


Rod,

For the most part I think I understand what your saying, but want to re-read another time or two before I hit you with any more questions.


Thanks!

[Ethan Winer]

Mitchell,

> If I were to make the walls and ceiling unparallel to each other, would that make a noticable difference in acoustics, maybe even negate the need for alot of extra treatment beyond the traps <

Angled walls and ceilings reduce flutter echo, but that's about it. Not to minimize that benefit, which is huge! But as far as I know the reverb time will still be about the same, and the need for bass trapping will be the same too.

One big benefit of angled walls is you can achieve more ambience and reverb in the room if you want them, because you don't need to apply as much mid/high absorption just to get rid of flutter echo. I'm not sure how much advantage a ton of reverb is in a control room, but it could surely be useful in a live room. You might also consider variable acoustics, such as drapes that open and close or hinged panels that are absorbent on one side only, for a recording room that is very live. That way you can vary between very live and less live.

--Ethan

Rod,
I made up a drawing to help to help me. Not to scale.


fig 1


__________________________outerwall_____
| _________inner wall__________________
| |
| |
| |
| |
| |
| |__________Inner wall_____ door _______
|
|____________airlock wall?__ door _______ | |
|
outer wall
|
|
--------------garage door----------------

Nice, huh? It's not fully enclosed due to some formatting conflict. I hope it's understandable

Well, I think I'm going to pass on altering the structure supports of the garage. It sounds like trouble waiting to happen.

Refering to the fancy diagram. is this what you meant by an air lock? And, in general, am I on the right track?

On the int walls, do I use drywall on both sides of the wall? If so, should I use resilient channel on both sides?

Also, should I consider the airlock wall to be an ext wall and treat it in the fashion you've described for them?

And finally, for now, the ceiling should be built on the other four walls and completely independent of the garage joists and treated the same as the other int walls. Correct?

Oh yea, will building the room "unparallel" have an effect on sound transmission?

And, another I just thought of. 2x4's, 2x6's or larger for framing this?


Ethan,
I like the idea of being able to have variable acoustics. And, it shouldn't be too much more trouble than making the room a standard shape. by the way, how drastic do I need to go with this for it to be effective on flutter, etc?

I think I'm going to have the roof pretty low, but it will be unparallel to the floor. Should it still be deadened. to avoid comb filtering or will it make a difference?

Ok, that's enough out of me. Thanks for all your help so far, Ethan, Rod.

[dymaxian]

You know what you could do if you REALLY wanted to spend some time on it...

Put drywall or MDF or particle board or whatever up on the 'upper roof' part and have your 18' high ceiling peak... and then on the lower joists you could lay 1" or 2" thick 703 across the tops of them. Or fasten them up to the bottom... whichever. Having them on the bottom would conceal the joists, having them on top would give you a little more sonic headroom, even if it isn't 'real' headroom for you to move stuff around.

This makes that 18' peak into a huge, variable depth bass trap.

Theoretically.

Ethan? Doug? This feasible?

Beware, though. I can just hear Rod's blood pressure rising thinking about manouvering sheets of drywall between those joists and installing it... So if you're doing this with the help of friends, don't be suprised if they don't call you for a while. Either that or be prepared to supply some decent alcohol for them afterwards... It's not that it's impossible, or that it'll be a huge pain in your @$$, it'll just be tricky.

I wonder if it may not be a horrible idea, in situations like this where a 4'x8' sheet is tough to manouver, to chop all the pieces in half. It would require twice as much taping, tho, so the added aggrivation might not be worth it. But you'd me moving half as much drywall at a time- it might cut down on the cursing...

Just thinking out loud...

Kase