I'm not gonna "break the Bank" doing this
But breaking the bank is what studio building is all about!
I thought it was a rule: If you didn't break the bank, then you didn't build it right!
Seriously, with 5k you can do something pretty good, but I'm betting that as you go along you'll find more and more reasons to think about that bank, and about breaking it... It's tha nature of tha beast: once the studio-build bug bites you, then there is no hope. There is no known antidote, and you are doomed to suffer the "if only" syndrome forever: the only relief to be gained is by throwing more money at it...
You keep talking about an inner and outer leaf. I assume you are referring to that as a "room within a room" design? I didnt really plan on doing that for this build.
If you want soundproofing, then you don't have a lot of choice!
You did say "So my first consern is soundproofing", and you do show a rather nice drum kit and some heavy-duty amps, so I assumed that you'd need decent isolation (soundproofing). And the only way to get that at a reasonable price is with "room-in-a-room" construction.
Let me try to explain: There are two aspects to building a studio. One is isolation (a.k.a. "soundproofing"). The other is treatment. Isolation stops the sound from getting out, and if it can't get out then it must stay in (duh!). If it stays in, then that makes your room sound bad, hence you need treatment, to make it sound good again. Isolation and treatment are two totally different and diametrically opposed things. Isolation requires massive, solid, hard, rigid, reflective surfaces. Treatment requires softy, light, fluffy, flexible absorbent surfaces. Contrary to popular belief it is impossible to isolate a room by simply hanging absorbent materials on the walls: that will TREAT the room, and it will sound better, so you might think that you dis some isolating, but in reality you did nothing at all: outside, things will still be just as loud as ever.
So, if your goal is to isolate a drum kit and some hefty amp cabs enough that the cops don't come knocking on the door, and the neighbors don't want to shoot you on site, and your family doesn't want to change the locks and leave you in the gutter, then you need isolation. If that is your goal, then the ONLY way to get the kind of isolation you need, on your budget, is with "room-in-a-room" construction. Just putting foam in the studs spaces will do next to zilch for isolation.
Think of it this way: the fundamental frequency of the kick drum is around 80 Hz. That means the wavelength is around 14 feet or 170 inches. To fully absorb that with fluffy insulation alone, you'd need to make it about 3 and a half feet thick (a quarter wave for 80 Hz is 42 inches).
On each wall, and on the ceiling.
And that's just for the kick drum: I see a bass cab in there, and a 5-string bass guitar goes down to around 35 Hz, easily. That's a wavelength of 32 feet, so you need about 8 feet thickness of insulation to cover the quarter-wave...
And even then, although you'd be covering the complete quarter wave, the attenuation would still not be great.
Clearly, insulation is not the answer. Sound waves follow the laws of physics, and the physics of absorption is not something that will make you jump up and down with joy, if you want to isolate drums.
The only practical way of stopping sound is with mass. But here again, the physics isn't on your side if you just plan to rely on your existing walls. The principle of physics that governs how well that single-leaf of mass isolates, is called "mass law". It says that each time you double the mass of the wall, the isolation goes up by 6 dB. Wonderful!!!! Not.---
6 dB is nothing: That wall that you have right now is probably giving you around 20-something dB of isolation. Your drums are putting out 110 dB, easily, and the full band more like 115 to 120. Your local municipal regulations probably set the legal limit for nuisance noise at maybe 40 dB. So you need to lose a total of around 60 to 70 dB. Call it 65 dB, for argument's sake. If your walls right now are giving you 25 dB of isolation, let's see how you could get there with mass law: Let's assume that you can double the mass of your wall by adding a layer of 5/8" drywall to it. So adding one layer will take you from 25 dB to 31 dB. Add another TWO layers (double again, total of four layers) gets you to 37 dB. Add another FOUR layers (remember, you have to double the mass
each time to get the extra 6 dB, so now you are at at total of 8 layers and 43 dB). Add another EIGHT layers (total now 16) gets you to 49 dB.... I think you see where this is going!!!! You are sill a long way from the 65 dB isolation that you need...
Adding mass to your walls is not a realistic solution.
So what IS the solution, if you want good isolation? You can't get it with absorption, and you cant' get it with mass, so what do you do?
You get it with a tuned filter. You build a wall that consists of two "leaves", separated by an air gap. Simple! You now are no longer limited by mass law, but rather by MSM law: MSM means "Mass-Spring-Mass". The "leaves" on each side of the air gap are the two "M's", and the air in between is the spring. This is a tuned system, and a very different set of laws of physics applies to it. It no longer just resits passively, like mass does, but it sort of "fights back" at the sound. If you tune it to a low enough frequency, you can get really good isolation from much less mass (and much less expense!) than either mass law or absorption.
So what you should be planning to do, is to add a new stud frame right next the existing stud frame that you have, just a half inch away from it, then put drywall on that frame, and fill the cavity behind it with insulation. Same for the ceiling: put new joists across the tops of your new inner-leaf walls, and hang drywall from that. Done! Excellent isolation, low cost.
So you can use the laws of physics in your favor with this method. It's not hard to do and it doesn't take a lot of money. It just has to be done right.
But lets just say LOUD. Really LOUD. Two full stacks, 8x10 bass rig, full drum set, and mid size PA for vox and triggered kick drum.
Yup. That drum kit alone is going to put out 115 dB, played hard. You guys are gong to get close to 120. So you NEED isolation, big time, I reckon!
We know that we are gonna have to tone it down ie; half stacks and turning down the PA. But Ill still need a significant amount of sound proofing.
Do the math: Turn them down to half the power, and that decreases the total sound pressure level by about 6 dB.... not very much! You'll have to turn them waaaaaaay down to not get arrested if you don't have good isolation. And there's another minor detail: There's no volume control on the drum kit!
You can't turn that down...
I would need deffinate decibel readings but I haven't found a cheap one yet and I'm trying to "pinch every penny" for this project.
They aren't expensive: You can pick up a really nice new one for under a hundred bucks on e-bay, and I've bought pretty good used ones for under 50.
I looked into that OC703 stuff. Its pretty expensive. Might me something I would wanna use for wall treatments after Im done and hear what the room sounds like.
Yeah, it ain't cheap, so if you are on a very tight budget then look for mineral wool with a density of around 50 kg/m3, and fiberglass with a density of around 30 kg/m3, and just buy whatever is the cheapest of those two in your area.
Gonna do 2 layers of 5/8 dry wall. And should I separate the 2 layers (air channel) or just have them together.
Ummmmmmm...... I thought you said you were not going to do room-in-a-room, but that's exactly what you seem to be doing!
2 layers of 5/8" drywall on a new stud frame next to the existing stud frame IS room-in-a-room! That's it, exactly!
Do not separate the two layers: put them right on top of each other, and "stagger" the sheets so the joints don't line up between layers. You will have an air gap between the existing wall and this new wall, and that's all you want. You should NEVER have more than one air gap inside a wall. If you do, then that damages the isolation.
Or, is there a cheaper substitute for the Green Glue I could use?
Nope! Unfortunately not. Or at least, nothing that has been tested and proven to work like GG does. But once again, you said you were on a tight budget, and here you are talking about GG. GG is great, and works very well to improve low frequency isolation, but it isn't cheap. If you can afford it, then use it by all means!
As far as sealent goes I was just gonna use an indoor/outdoor calking.
Green Glue Company also makes a really good acoustic sealant, so if you are going to order Green Glue for between the layers of drywall, then maybe also order a couple of cases of their sealant. It isn't that much more expensive than good quality caulk, and is designed to do the job right.
As far as heating and air goes, everyone keeps telling me that if I use enough insulation, that it would stay a pretty comfortable temp all year round.
I think you are listening to the wrong "everyone" then!!!
Think about this: half dozen guys in a small air-tight, double-sealed, double-insulated room, jamming really hard, working up a good sweat, with some big-ass amps, cabs and other equipment going full bore.... we are talking about a lot of heat there! Lots of BTUs coming off you guys and your equipment. Not to mention the humidity you are putting out, and the rather annoying habit that all people have: breathing! We take in oxygen, and put out CO2 (among other things). I'll give you about half an hour in there, before you notice that it just ain't "pretty comfortable" in there any more...
It will be pretty warm, pretty muggy, and smelling pretty bad, and that will happen pretty fast... "comfortable" is not the way I'd describe it!
Don't forget that your room will be sealed hermetically, twice over, as part of the isolation. You'll also have a two very thick layers of insulation around you, so no heat is going to leave that room. What's in is going to stay in, and build up fast. That room, in Texas... It's going to smell, shall we say "ripe" in there...
You NEED ventilation. No question about it: You MUST bring in fresh air and exhaust the stale air. that's the very least you need, but even then that doesn't solve the heat problem. Human bodies at rest put out about 400 BTU per hour, and musicians jamming hard could be putting out 1,500 or even 2,000 BTU per hour. Five of you in there makes for 10,0000 BTU per hour. Add another few thousand for your equipment, and you have a LOT of heat! That's like having several electric heaters going in there, all at once.... You NEED to cool the room.
I thought about a window unit that has heat and cooling but all my sound would escape right out of it.
Exactly. Not to mention that window units are NOISY!!!!. Not a good solution.
What if I made some kind of insulated box that could go over it (inside and outside) and just dont run it while we practice?
How long can you hold your breath?
Seriously, your basic idea is right: build a silencer box. But the application is wrong: Don't try to silence the HVAC unit: rather, put the noisy part outside and silence the ducts!
Spend some time searching the forum for things like "HVAC" and "silencer", and you'll see numerous ways of dealing with the problem. The cheapest way is probably to put in a small mini-split system to cool and dehumidify the room, and a couple of simple ducts with fans and silencers to bring in fresh air and exhaust stale air. Not too expensive, but also not cheap! However, it is very necessary.
I dont know if $5k is gonna get it all done. I have to do the ceiling, door, window, electrical, insulation, drywall, HVAC(maybe), lighting, carpet (I'll do hardwood floors later), Paint, wall treatments, and make my vocal booth. Thats gonna spread me pretty thin.
So with all that in mind. What corners can I cut and what do I have to do RIGHT?
You have to do ALL of it right!
OK, so there are some ways you can save money. For example, Green Glue is great stuff, but can you afford it? An extra layer of drywall will have about the same effect as the green glue, so do the math and see which is cheaper. Or if you are willing to sacrifice a bit of space, you can make the air gap inside your walls bigger, and not add either GG or drywall! Once again, it's back to the "tuned MSM wall" thing. The equations for tuning the wall depend on two things: Mass and air gap. Increase mass, you get more isolation. But increase air gap and you also get more isolation. The mass costs money, but the air gap is free! So if you can afford to leave a 6 inch gap between the existing walls and the new walls, then you wold not need the GG or the extra drywall: just two layers of drywall with the bigger gap would give you the same total isolation as 3 layers and the smaller gap (or GG and the smaller gap).
Also, skip the carpet! It is lousy for acoustics (does the exact
opposite of what you need), and just use the bare concrete floor for now. That's a great surface, acoustically.
And skip the window! A window that isolates is VERY hard to do right, and very expensive (2 panes of thick laminate glass will take a huge chunk out of your budget). If you can live without it, then forget the window!
And make the doors yourself! Don't buy proper acoustic doors: those things are expensive. You can make yours much cheaper, based on plain old solid-core doors that you can pic up at Home Depot. (not foam core, and not hollow core! Must be solid core). Screw and glue a layer of MDF or plywood to each door, put triple seals around the edges, and for a few hundred dollars you'll have an excellent pair of isolation doors.
Also, skip the vocal booth for now: Unless it is life or death, you don't need to make it now. OK, so making it later means modifying what you are about to build now, but you can save money by not building it yet. That's an extra pair of doors, extra HVAC, extra electrical, extra lighting, windows (maybe), ... If you you need to save money, drop that for now and just build a couple of gobos to give you at least some separation. Much cheaper.
Also, room treatment: That came come later. It's very, very hard to add isolation later, but very easy to add treatment later. Sure, the room will sound lousy initially, but at least it will isolate! And it will give you the incentive find more money fast, to do the treatment...
Etc.
There are ways you can save, if you think about it. But there are a couple of areas where yo CANNOT skimp. First, do not skimp on sealing: sealing everything air-tight is critical for isolation. Second, decoupling. You CANNOT isolate the room successfully if you do not build that 2-leaf MSM wall, where nothing touches. You have an outer leaf (what is there already) and an inner leaf (what you still have to build), and they must not touch each other. What you build is a separate structure, that sits on the same floor but has nothing else in common.
There's more, but that should be food for thought, to get you going!
- Stuart -
