sound proof enclosure for air compressor and dust collector question.

[Travis Conner]

Do you have to close off the top of the enclosure? I kind of just want to use plywood and make it wrap around the compressor and dust collector, but make it go like 2ft taller than each machine, then put in a fan on one of the walls to circulate the air inside. So basically insulate the plywood and enclose it all except for the top. Would that still cut down on sound a bunch? I don't like some of these enclosures that completely close off the machine, i feel it's going to cause them to run too hot. And yes the dust collector and air compressor will be in separate enclosures, not together. Just want to make sure the neighbors hear the least amount of noise as possible, even though the nearest neighbor is about 100 feet away and that's the garage, their house is probably 150ft away.

[Frank Pratt]

I have both the dust collector and air compressor in a common, sound attenuated enclosure. There is an acoustically insulated, serpentine return air duct to the shop. That takes care of all the air needed to cool things. It's very effective.

[Travis Conner]

When you install an in wall fan into the box, so you install it so the fan is blowing outside air in or inside air out of the box?

[Travis Conner]

https://www.northerntool.com/shop/tools/product_200814909_200814909?utm_source=criteo&utm_campaign=57525&utm_content=2028971554

[Bill Dufour]

any small opening lets out a lot of noise. it has to have a bottom, a top and all sides closed off. crack open a house window just one inch and see how much car noise comes in. I am still waiting for active noise canceling for a dc and or ac unit.. seems like it should be easy with a very limited range needed. maybe just one silenced duct for in/out with the rest soundproofed.
Bill D

[mike stenson]

https://www.northerntool.com/shop/tools/product_200814909_200814909?utm_source=criteo&utm_campaign=57525&utm_content=2028971554

I have one of those venting my shop.. If you're blowing air into the box, it's got to vent elsewhere (and that fans gonna need about 2-3sqft of vent most likely).

[Travis Conner]

Yeah I guess you want it to blow outside.

[Bill Yacey]

Your air compressor is a pump. It has to draw air from somewhere before it can compress it. A sealed, enclosure will quickly create a vacuum as the compressor draws all the available air from the enclosure.

[George Makra]

Sound and vibration are related so put your compressor on rubber pads.
You can build an enclosure and put Styrofoam or cork or something soft that the sound cannot reflect off of.
Your are cleaner would require some duct work
To make it quiet.

This will help reduce the noise but will not eliminate it.

[Jim Becker]

Yes, I do. Lots of threads on this here, too.

I have a closet for both the compressor and cyclone that is designed for sound abatement and with an indirect return path to the shop for air.

[Bill Yacey]

I installed my compressor in the attic, and plumbed the air line down through the wall to a pressure gauge and a Lincoln air connector. Power switch is a switch on the wall beside the air outlet.

[John K Jordan]

Do you have to close off the top of the enclosure? I kind of just want to use plywood and make it wrap around the compressor and dust collector, but make it go like 2ft taller than each machine, then put in a fan on one of the walls to circulate the air inside. So basically insulate the plywood and enclose it all except for the top. Would that still cut down on sound a bunch? I don't like some of these enclosures that completely close off the machine, i feel it's going to cause them to run too hot. And yes the dust collector and air compressor will be in separate enclosures, not together. Just want to make sure the neighbors hear the least amount of noise as possible, even though the nearest neighbor is about 100 feet away and that's the garage, their house is probably 150ft away.

Probably no such thing as "sound proof" but sound reducing. Absolutely insulate the top too or the sound will go up and bounce off the ceiling. I have cyclone and air compressor, both with 5 hp motors, in a 4x8 closet with insulation all around. The air is returned through a baffled duct that changes direction several times. The motors don't get excessively hot (are within specs) even with extended use.

Sound can be transmitted directly through plywood walls almost like a sound board on a piano unless well insulated. I used 1/2" ply inside and out but didn't support the ply with studs that touched both sides - I used staggered stud walls with insulation wound between. This is sometimes used in sound studios. I used 2x4 studs on 6" thick walls.

439904

The reduction in sound is incredible. The cyclone was so loud it was painful, the compressor was so annoying. Now I can easily carry on a conversation in the shop.

[mike stenson]

My old shop adjoined our living room. It was the most convenient shop I ever had. When I built the wall, I did 2x6 staggered studs.. and filled the cavity with rock wool, and skinned it with 2 staggered layers of 5/8" rock. No one complained about noise. The technique works really well.

[Travis Conner]

Well the first thing I'm going to do is turn on the compressor, walk 50ft out into the road and see how loud it is to begin with. Maybe I can get away with not doing the compressor and just do a box for the dust collector. I'm not as concerned about cooling with the dust collector. The air compressor is a quincy, so it's not too loud to begin with.

[Alan Lightstone]

My compressor / cyclone room is also about 4' x 8'. The best soundproofing I came up with for a small budget was moving blankets. Thicker the better.

They cut the sound level coming out of the closet by more than 10dB.

Check out Amazon for them. Cheap and works. Of course, if you could do real sound insulation like Roxul Safe N Sound with an air gap, even better. For my workshop I used double 5/8" drywall with Green Glue between layers on each side. 2x6 walls with Roxul Safe N Sound insulation.

This drops noise levels over 30db, which is incredible.

[Travis Conner]

My shop has a loft connected to one side that's about 8ft tall. I think what i'll do is make a hallow wall made with studs and plywood, with about 6'' of insulation stuffed inside of it. then move those around the compressor which is placed in the very corner of the shop. Think of it like a welding shield that welders put up that makes it so people nearby don't hurt their eyes, only in this case it's from noise.

[John K Jordan]

My shop has a loft connected to one side that's about 8ft tall. I think what i'll do is make a hallow wall made with studs and plywood, with about 6'' of insulation stuffed inside of it. then move those around the compressor which is placed in the very corner of the shop. Think of it like a welding shield that welders put up that makes it so people nearby don't hurt their eyes, only in this case it's from noise.

You might consider getting a sound meter to help evaluate the noise reduction. There are a bunch available on amazon some are very cheap. This is the one I have:
https://www.amazon.com/dp/B000EWY67W


JKJ

[Alan Lightstone]

You might consider getting a sound meter to help evaluate the noise reduction.


JKJ
I just use an iPhone app to look at things. I'm sure it won't win accuracy awards, but it's good for seeing effect of different methods of soundproofing.

Armstrong Ceiling Solutions has an iPhone app for this (Armstrong Sound Level Meter). Can't remember if it was free or not

[Jim Becker]

Another thing that can help is actually planning for general noise abatement in the shop. While I'm not suggesting that everyone put in a full ceiling with acoustic tile like I did, I can honestly say, it RADICALLY transformed the noise levels in my shop because of how it killed reflections from hard surfaces. Everyone can take advantage of this concept by putting in some sound absorbing panels or whatever. Many places like retail and restaurants that embraced the "open ceiling" concept found they have to do this to make the space even remotely pleasant for folks to be in there and that was with the primary noise source being people's mouths rather than machinery. My ceiling combined with the closet for the compressor and DC makes for a very pleasant environment to work in.

[Travis Conner]

Yeah Jim There is a pizza place and a sandwich shop I go to and the ceilings are like 30ft high. You can't hear anything the person says because it just echoes. Inthink they have that grey popcorn spray insulation.

[Travis Conner]

And it's actually not an echo it's hard to describe, it's like you're hearing the person's voice go around the room instead if towards you.

[Ole Anderson]

https://www.youtube.com/watch?v=8X8qwMqm3Ek&ab_channel=aandersonmi

[John K Jordan]

And it's actually not an echo it's hard to describe, it's like you're hearing the person's voice go around the room instead if towards you.

Technically, it's an echo, or actually, a number of echos. An echo is a reflection that is delayed in time from the original sound, all based on the difference. Sounds, electromagnetic waves like radar, light, waves on water, etc. Echoes can cause problems when they reflect undesirably, for example bounce back down an electrical line from some interface.

A shout from a mountain top that comes back from another mountain or clift of the proper shape and at a good distance can have a primary reflected sound so strong you can hear a repeat of the word or phrase you shout. You can often hear an echo from the bottom of a deep well.

An echo inside an irregular cave can produce an incredible reverb because so many sound waves are coming back at very close intervals - it can sound beautiful. (We experienced amazing sound from a friend playing hymns on a trumpet in a cave that was the most incredible thing I've heard in my life.) Concert halls and large auditoriums are designed to carefully control the echos from various surfaces, amplifying and suppressing reflections from carefully constructed surfaces built at precise angles and curves. Hard surfaces bounce sound sound waves efficiently. Soft surfaces absorb sound. Curved and angled surfaces can focus or direct sounds. The conflicting delays in times of arrivals can create auditory confusion.

A large room with flat, hard surfaces can create so many conflicting echos they can interfere with clear sound. Yes, the sound may "go around the room" by bouncing from a variety of surfaces before it reaches your ears. A poor "chamber" can in fact be unpleasant, especially with multiple sound sources.

There is much information available on echos. This is a simple overview: https://en.wikipedia.org/wiki/Echo

JKJ

[Bill Dufour]

rockwool insulation is the only one rated to be left exposed and not burn. The glue in fiberglass insulation burns. I would line the enclosure with rockwool batts to soak up the sound. Roxul makes "safe and sound" designed to soak up noise inside a wall.
Bill D.

https://www.rockwool.com/products/safensound/?gclid=EAIaIQobChMItN7Pn7b56wIViZOzCh3uxAVpEAAYASA AEgJiO_D_BwE&selectedCat=safensound%C2%AE%20downloads

[Mel Fulks]

I've used the Roxul, the company makes 2 products that are packaged too much alike. One is for insulation, and the
other for sound. Read the labels.

[Bill Dufour]

I've used the Roxul, the company makes 2 products that are packaged too much alike. One is for insulation, and the
other for sound. Read the labels.

I am not really convinced they are any different. The sound one has no insulation "R" rating value. The "R" rated one is better then fiberglass per inch. I wonder if the sound rated one is the same as fiberglass as far as "R"rating? For some reason in California, home of energy saving government policies, there is no R15 fiberglass only R13.
Bill D

[Frank Pratt]

I am not really convinced they are any different.

STC testing shows there is a difference, though I don't think it's huge.

[mike stenson]

FWIW, rockwool was unobtanium a couple months ago.

[Mel Fulks]

FWIW, rockwool was unobtanium a couple months ago.

Then I would use the ground up news paper stuff, "dense packed" in plastic bags. More work but cheaper and more
effective.