John Sayers' Recording Studio Design Forum Archive

Hello everyone,

I've been running sound for a venue in Cleveland for 4 years now. I need some help with some sound barriers.

The problem
1. the building was built in the 30's and was solid brick. When the owners bought the building they installed two 12ftx13 double pained garage doors side by side at the front of the building. This is where the music venue is located. the framework is alluminum with 2ft by 44 in window panes double paned. The Music space is about 40ft by 40ft roughly. The complaints are coming from an apartment building behind the venue. Mostly from the same guy. Its a loud room 115db easy. We've added acoustic ceiling tiles throughout. There is a wall with another room GREEN ROOM before the back alley we share with the apartment building.

I'm building sound barriers for the windows. We already have a sound proofing curtain there but it doesn't seem to be enough. The framework is already built so I have to work with what i got. the dimensions of the boxes are 8ft by 12ft by 12inches wide wide on castors so they can be moved. The boxes are solid and well made but I'm trying to figure out insulation. Denim vs. Cellulose vs. ????. Bass frequencies are the problem here and we don't have a lot of money to throw at it. and there is no ordinance for it. meaning it's at the cops discretion which is always hit and miss. some will just come to the glass hear it blaring and equals ticket. others take the time to go to the back ally hear its bass and have us try to control that. Point is it's always the bass being a problem.

anyone got any ideas? heres what I was planning

1. Open up and blow cellulose into boxes, use thick styrofoam and green glue on the other side of walls leaving a bit of space. i was also going to use wood panels in between the studs to help with the resonating frequencies of the studs. Kinda like a diffusor. My concern is while the cellulose is cheap the 5 gallon bucket of green glue was not so much and I don't want to use it here if it isn't going to help at all. I was also going to build 6 panels to fit individually into the window panes that the box doesn't reach in height. it would be from inside looking out plywood green glue styrofoam in those. I will probably put the last two boxes of 2x2 sound panels on the wall to help the room reflections a bit.

I really need to know what will help with bass frequencies with what I have and keeping it rather cheap in the price range of 100-150 with the insulation, and if using the green glue will help at this point

Thanks

Hi. Please read the forum rules for posting (click here). You seem to be missing a couple of things!

We've added acoustic ceiling tiles throughout.

That won't do much at all. It certainly will not stop sound getting out, and will only marginally help with acoustics inside the room. That's not what "acoustic" tiles are meant for: they are designed to help control typical office sounds, in typical offices. Not useful at all for extremely loud music.

We already have a sound proofing curtain there but it doesn't seem to be enough.

whoever sold you those was not telling you the truth: Curtains are not and cannot be "soundproof". That's about as logical as saying that a a sponge is "waterproof"...

Certain types of curtains can help to control acoustics INSIDE the room, but just like the ceiling tiles, they won't be a lot of help in stopping sound getting out.

... on castors so they can be moved

Sorry, but that won't work either! You have basically built a wheeled gobo, which is great for controlling acoustics INSIDE a room, but once again is useless for stopping 115 dB of loud music... Don't wast your time by continuing to build those...

The boxes are solid and well made but I'm trying to figure out insulation. Denim vs. Cellulose vs. ????.

Neither: Insulation CANNOT stop sound! That's a common myth, but very wrong.

Yes, insulation DOES have very valid uses in acoustics, and can indeed be part of a wall that actually does block serious amounts of sound, but by itself it does nothing useful.

Think of it this way: a sponge is a great thing for mopping up water that spilled some place you didn't want it in the kitchen, but if you hold it across the end of the tap while the water is running, it does NOTHING to stop the water: insulation is the same: it is great for treating sound that "splashed" around inside the room where you didn't want it, but useless for stopping sound getting in or out.

Bass frequencies are the problem here

Yup. Absolutely, and without any doubt. The thumping drums and growling bass will be easily heard, quote a distance away, when you have basically no isolation.

we don't have a lot of money to throw at it.

You don't necessarily need a huge amount of money, but you do have to use the right materials and the right techniques. Acoustic tiles, curtains, and wheeled gobos stuffed with insulation are NOT the right ones.

use thick styrofoam

Styrofoam has absolutely no uses at all in acoustics. (Except in the form of a coffee cup: then it is useful). Styrofoam is closed-cell, and therefore worthless for acoustic treatment, and even more worthless for isolation. It is great as thermal insulation, but zero utility as acoustic isolation.

green glue on the other side of walls

Green Glue is a constrained layer damping compound. It does NOT go outside the walls! It is used in between two layers of mass that together form one side of a decoupled MSM isolation wall. Using it any other way is pointless.

i was also going to use wood panels in between the studs to help with the resonating frequencies of the studs.

No. Not useful.

Kinda like a diffusor.

Once again, diffusion is a useful tool for controlling sound INSIDE a room, but has zero effect at stopping the sound from getting out. That's not what diffusers do, and not how they work.

the 5 gallon bucket of green glue was not so much and I don't want to use it here if it isn't going to help at all.

GG is excellent stuff, and really does work... but ONLY when used correctly, as part of a properly design and calculated isolation system.

I was also going to build 6 panels to fit individually into the window panes that the box doesn't reach in height. it would be from inside looking out plywood green glue styrofoam in those.

That's a useless sandwich, on so many levels. It would basically do nothing more than the plywood all by itself, which isn't much.

I really need to know what will help with bass frequencies with what I have and keeping it rather cheap in the price range of 100-150 with the insulation,

You probably don't want to hear this, but you are seriously out of luck if that is the limit of your budget.

The ONLY way to stop sound is with a mass, plus decoupling, plus damping, plus hermetic seal. That means you need a very thick very heavy panel (such as plywood, drywall, or glass) that is attached to a supporting frame, then you need an air gap that is filled with acoustically useful insulation such as fiberglass or mineral wool of the correct density, then you need another very thick very heavy panel (such as plywood, drywall, or glass) that is attached to a second supporting frame, such that the two frames do not touch each other at all. Then you need to seal both of those completely air-tight. If you leave even a slight crack where air can get through, then sound can get through too.

You would need to do this to the entire room, not just one window on one wall. If you only do part of a wall, then the sound will just ignore that part and go around out, getting out through the part that you didn't do. If you do one entire wall but not the other walls or the ceiling, then the sound will ignore the good wall that you built, and get out through the other walls and the ceiling. If you do all the walls and the ceiling but not the doors, then sound will ignore all of those and get out trough the doors.

Acoustic isolation of a room is only as good as the weakest part. To get decent isolation, all of it has to be isolated to the same level.

How much are your fines costing you? I'm betting that it is quickly adding up to far more than US$ 100... So maybe you should consider spending all that fine money that you would be saving, on proper planning, proper design, and proper isolation. If not, then you'll just carry on pouring it down the drain, and sooner or later the cops or your neighbors will get a court order and shut you down permanently...



- Stuart -