soundproofing drums

[carbonscoring]

About to buy a beginner drum kit. I need to soundproof the room that I will be practicing in. Its a spare bedroom with carpet that is roughly 12 x 14. It has one window and the walls are drywall.

Any suggestions on making my own soundproofing or a website that would have proper placement of what kind and where to put such material. I don't want to upset my neighbors when I practice. I know it's expensive but, I don't want to spend money in places that I don't have too or buy something that wont work.

thanks in advance,

Mike

[bennychico11]

start by searching here...in this site (search button up top)

Big difference between absorbtion and soundproofing. Placing absorbtion can help lessen the sound of the drums from escaping the room and is much cheaper. Soundproofing is basically talking about reconstruction of the room and gets very pricey. The kick drum is going to be your work enemy in this (especially if you're in an apartment or something).
Start here: http://www.saecollege.de/reference_material/

[pandamonk]

Originally Posted by carbonscoring

About to buy a beginner drum kit. I need to soundproof the room that I will be practicing in. Its a spare bedroom with carpet that is roughly 12 x 14. It has one window and the walls are drywall.

Any suggestions on making my own soundproofing or a website that would have proper placement of what kind and where to put such material. I don't want to upset my neighbors when I practice. I know it's expensive but, I don't want to spend money in places that I don't have too or buy something that wont work.

thanks in advance,

Mike

You can't get placeable "soundproofing".

Sound ISOLATION comes from mass and no air leakage. I doubt that they're will be any leakage, so you need to work on mass.

The most efficient use of mass, is in a mass-air-mass structure. Now, you probably have this already, drywall-air-brick, or whatever. This will give you a decent amount of isolation, although will still leak. I'd say, your weak link would be the window, and probably the roof. These are what you will have to focus on as isolation is only as good as your weakest link.

A double glazed window works well, but has no where near the isolation of your wall, so needs to be fixed. Now mass-air-mass works better than mass-air-mass-air-mass, so you can't just add another layer. You need more mass and more air, which means thicker glass, and a much bigger gap.

Now your ceiling/roof will be pretty bad also, so you need more mass here too. I'll let someone more experienced advise you with this...

[pandamonk]

Originally Posted by bennychico11

start by searching here...in this site (search button up top)

Big difference between absorbtion and soundproofing. Placing absorbtion can help lessen the sound of the drums from escaping the room and is much cheaper. Soundproofing is basically talking about reconstruction of the room and gets very pricey. The kick drum is going to be your work enemy in this (especially if you're in an apartment or something).
Start here: http://www.saecollege.de/reference_material/

Absorption does nothing of the sort...

Absorption dampens the noise within the room. It does not reduce the sound escaping the room.

[elementary]

It does not reduce the sound escaping the room.

It will reduce it a bit surely, if sound energy is being absorbed, less is going to be available to penetrate the walls?

[Rod Gervais]

Originally Posted by elementary

It will reduce it a bit surely, if sound energy is being absorbed, less is going to be available to penetrate the walls?

If the entire room was covered with 24" thick absorbing materials (all 6 surfaces - at 100% each one) it wouldn't amount to a small percentage of the sound escaping the room.

Panda is right - you CANNOT reduce sound leaving a room (i.e.; create isolation) through the use of room treatments.

Sincerely,

Rod

[Rod Gervais]

Originally Posted by pandamonk

Sound ISOLATION comes from mass and no air leakage. I doubt that they're will be any leakage, so you need to work on mass.

Sorry Panda, but that isn't right.

The average house constucted today has .6 complete air exchanges per hour.

A LEEDS building - which is the tightest spec there is, only brings that down to .3 complete air exchanges per hour.

At .6 - a 1200 s.f. home with 8' ceilings would have 5760 cubic feet of air per hour of infiltration - which averages out to 96 cfm.

His problems are going to be a combination of lack of mass - lack of air seal - glass window - with his bigest problem (if he caulked everything - sealed the windows - and added a couple of layers of drywall to walls and ceiling) would be flanking.

To acheive what he wants is going to cost a substantial aount of money.

Sincerely,

Rod

[bennychico11]

Originally Posted by Rod Gervais

Panda is right - you CANNOT reduce sound leaving a room (i.e.; create isolation) through the use of room treatments.

Sincerely,

Rod

why is this?
reverb time of reflections around the room can be minimized greatly, but the sound passing through the same absorbers can't? I know you'll never achieve "sound-proofing" but would it not help at all?
What about creating panels/baffles of some sort and building a circle around the drums. Would that not help sound transmission? Similar to the way Ethan suggests killing some of a desktop computer's noise by surrounding the PC with a few panels

[Rod Gervais]

I am sorry - but as I said - all of your wanting it to be won't make it so -

You are afffecting so little of the actual energy in the space (especially as the frequency drops) that the difference won't be measurable.........

To create isolation requires 3 things - the first is mass mass and MORE MASS.......

The 2nd is airtight construction - because where air goes sound goes......

And the 3rd is the air spring created in a properly constructed 2 leaf system.

you ask

reverb time of reflections around the room can be minimized greatly, but the sound passing through the same absorbers can't?

ANd the answer is "NOPE"

It's one thing putting enough treatments in a room to create a sweet spot for the listening position - understanding that you can't create a room that will sound perfect everywhere.

It's another thing to expect that little bit of "captured" energy to act like an MAM system.......

The very same sound wave will hit multiple room treatments in it's travel through a room - but whatever sound makes it through the treatment that was going to pass through the wall (for example) will still pass through the wall..

Picture what is involved with stopping it even with mass itself-

Suppose you have a wall / ceiling system that will cut 180 Hz by 20 dB........ and let's say that the system is made up of 2 layers of drywall on each face........

IN order to turn that that 20dB into 26 dB you would have to double the mass - ON BOTH SIDES OF THE WALL CEILING ASSEMBLY.

Just think about that - and then you tell me- how much are you going to get using some foam or rigid fiberglass........

sincerely,

Rod

[ofajen]

Originally Posted by bennychico11

why is this?
reverb time of reflections around the room can be minimized greatly, but the sound passing through the same absorbers can't?

The question here is about transmission loss, not reducing the relaxation time of normal room modes. The energy of the bass drum is mainly down in the under 100 hz part of the spectrum. An insulating sound wall is mainly defined by the surface density (lbs/sq ft.) Most room treatments barely even register on this scale. Compare the surface density of medium density fiberglass with the 7.3 lbs/sq ft of a stud wall or the roughly 100 lbs/sq ft of my poured concrete walls and ceiling.

Standard stud walls have an STC of 34 dB plain or 36 dB with fiberglass inside. This STC is also about equal to the transmission loss at 500 Hz for such a wall. However, the STC is a single rating number for a function that is highly frequency dependent. Transmission loss is typically 10 dB less at 100Hz than at 500 Hz and I would expect that at 20 Hz it's another 10 dB less if not more. So a standard stud wall is much more transparent in this frequency range (maybe a transmission loss of 15 dB). Because of their low surface density, most room treatments do little in this frequency range (probably less than 5 dB). It's true that with extensive bass trapping you can get the relaxation time of the normal modes of the room under control, but there you're dealing with the dynamic response of normal modes created by the reflective boundaries (walls) of the room.

Cheers,

Otto

[bennychico11]

okay, cool I gotcha both. Thanks for that.
really my response wasn't to question your knowledge or to "hope" that you were wrong, Rod...just curious to learn more about studio construction, isolation, absorbtion, etc., that's all.

[pandamonk]

Originally Posted by Rod Gervais

If the entire room was covered with 24" thick absorbing materials (all 6 surfaces - at 100% each one) it wouldn't amount to a small percentage of the sound escaping the room.

Panda is right - you CANNOT reduce sound leaving a room (i.e.; create isolation) through the use of room treatments.

Sincerely,

Rod

Hi Rod. Not seen you around for a while. Thanks for clarifying what i said.

Lee

[pandamonk]

Originally Posted by Rod Gervais

Sorry Panda, but that isn't right.

The average house constucted today has .6 complete air exchanges per hour.

A LEEDS building - which is the tightest spec there is, only brings that down to .3 complete air exchanges per hour.

At .6 - a 1200 s.f. home with 8' ceilings would have 5760 cubic feet of air per hour of infiltration - which averages out to 96 cfm.

His problems are going to be a combination of lack of mass - lack of air seal - glass window - with his bigest problem (if he caulked everything - sealed the windows - and added a couple of layers of drywall to walls and ceiling) would be flanking.

To acheive what he wants is going to cost a substantial aount of money.

Sincerely,

Rod

Again thanks for showing my mistakes, and clarifying.

[Rod Gervais]

Lee,

Thanks for the warm welcome - I've been busy and still am - but still try to float in once in a while - usually you guys have things pretty well in control and there isn't much for me to commment on......

SIncerely,

Rod