Anyone Have Experience With Low Frequency Soundproofing?

Lead. You will never be able to sell your house if you did that.

While you can change the resonance frequency of the wall, you are still left with finding a way to translate the acoustic energy to heat.

There are commercially available soundproofing curtains that are vinyl-encased lead sheets. They won't pass the interior decorator test and will require heavy duty mounts but they will block sound.

What kind of barriers have you tried between the wall and the driveway?

You may be surprised how well a simple hedge row or board fence can reduce noise.

Have seen people fill the space between a double wall board fence with foam to reduce road noise.

My GF has a snoring problem....I wonder if I could build a double wall board fence down the middle of the bed...

makes me crazy...

Chris,

Beware of the unintended consequences. You may solve the problem by virtue of the fact that she may no longer be your girlfriend. What ever you do, don't try a potato in her tail pipe.

thank you all... its a touchy subject already.. I'll have to find a way to bring it up.

back on topic... there were discussions on cr4 before about low frequency sound.

http://cr4.globalspec.com/thread/40999/Sound-Proofing-Basement-Bedroom
http://cr4.globalspec.com/thread/51342/Noise-Pollution

Chris

Upgrade your windows to double or triple pane. Windows are very vulnerable. Recording studios use multiple layers of thick glass and the glass is hung so the two panes are not parallel to reduce resonances.

The walls should be treated with an extra layer of drywall with a product called Green Glue between them. This produces something called Constrained Layer Damping.

Green Glue and the application notes can be ordered directly from here:

Green Glue

This should give you as much as 20 dB reduction if there is fiberglass insulation in the outside walls (typically this is the case).

Finally, sound may enter through the eves of the roof and radiate through the ceiling. Owens Corning (i.e., 703 and 705) makes a dense fiberglass product that some people call rock wool. The absorbent quality of this is better than normal batt fiberglass, which doesn't fare well with low frequency absorption.

The bottom line is that you want to transform the acoustic energy into heat. Constrained layer damping and rock wool will do a very good job of that.

The last resort is to put something in his oil at the dark of night. Check with your local auto dealer. They used some formula fro the trade ins for the cash for clunkers program that works very well.

Sodiium metasilicate is often called sodium silicate or 'waterglass.'

http://online.wsj.com/article/SB124934376942503053.html

"Better things for better living through Chemistry."

Milo

Maybe I should have put a little smiley face after the suggestion of the midnight raid. :-0

Adding heavy vinyl sheeting first followed by another layer of sheetrock works better for low frequency blocking.

an informative links

http://www.googobits.com/articles/228-home-improvement--an-overview-of-doityourself-soundproofing.html

instruction to apply sound proofing to existing finished walls:

http://www.doityourself.com/stry/soundproofceilingwal

sound proofing windows:

http://soundproofingwithdave.com/2007/09/soundproof-windows.html

I've got double pane windows that do an amazingly good job of deadening outside sounds.

Also, though I've never used it myself, some people have had good results using Roxul insulation in their walls.

http://www.roxul.com/stone+wool/sound-absorbent

Roxul is essentially the same thing as Rock Wool and dos a superior job to home insulation fiberglass.

Unfortunately, it is a bit difficult to install after the wall is already built. ;-)

...especially when you're sitting in jail 'cause he caught you tampering with the oil in his truck!

Probably a good bit more quite in there.

Bowling Ball

AH and Milo are very well respected by me.

Sans rebuilding parts of your home, I suggest thick heavy curtains.

Might want to check out the new metamaterial sound insulation panels developed by these guys in Hong Kong. Some details of the design are given in this PopSci article.

Panel absorbents would probably do the trick. This could be to the loss of interior space but cost effective to mitigate low frequencies.

For design & reference you might want to get a copy of "Acoustics, Noise and Buildings" by P.H. Parkin, H.R. Humphreys and J.R Cowell.

On the other hand, check with City Hall for any by-law that prohibits parking of industrial equipment in residential areas.

Good luck.

Vince

Have you considered having a chat with your neighbor about his loud pipes? They probably violate a local noise ordinance or three if they are that loud. If you have no luck with the neighbor you should consider having a chat with a member of the local constabulary about it. If you still experience no joy, you should consider chatting up a local ambulance chaser and have the gent served with a sealed invitation to speak about the situation in front of a magistrate.

If none of the above obtain relief, you could always cut a brake line... =b (I'm joking of course...)

Potato in the tailpipe?

In the UK, one has to have an Operator's License to operate a commercial vehicle. This is renewable every few years and I know the authorities take into account any complaints received from neighbours. They are able to impose restrictions on use including leaving and returning hours.

Finding out your local requirements on vehicle owner/operators would be a good start. In the UK the DVLA (Driver and Vehicle Licensing Authority) would be the point of contact - in the US I guess the DMV would be the starting point.

Rose, I think you misunderstand. He is speaking of a pick-up truck (which are quite common in the US as private vehicles, I own one myself, although mine is a small, unmodified rice burning one... they are practically the state vehicle of Texas after all...) which has been altered with various aftermarket modifications. There is no special licensing requirement for a pick-up truck, as it is not a commercial vehicle. Pick-ups are not terribly common in Europe, they don't fit your roman chariot trails that were converted to vehicular roads, they take up a lot of room when parking, they tend to burn more gas than a car (not insignificant given how much money your government saps you for in fuel taxes) to boot. We have few of those problems here in the US. But some people take it to the extreme....

the federal fuel tax is 19 cents/gallon, the state of texas adds 20 cents/gallon to that with gas prices hovering around $3 the taxes are not a very significant part 13%

VisiGuest, I meant the fuel taxes in Europe which are astronomical compared to Texas fuel taxes. fuel costs there are out of this world and almost ALL of that cost is tax.

We pay around US$1.00 in taxes PER LITER!!!!! Mineral oil tax is €0.83 and also on the whole price (Tax and cost of the liter) we pay VAT at 19%......

I believe a US Gallon is around 3.8 Liters.......

So the tax alone for a gallon would be around US$4.00!!!

Gas Liter price here is €1.45, about US$1.81 or around US$6.88 a US Gallon.....

So don't complain about price please!! You have your gas really cheap!!

Diesel is slightly cheaper here and the cars get better MPG over gas guzzlers....

Right. Or maybe you have some sort of an anxiety disorder that makes you sensitive to noise? I mean, if you're considering lead curtains and such...

Titi-the-rabbit

As stated earlier- one of the BEST ways to cut low frequency sound is lead sheets- encased in polyvinyl ideally to prevent oxidation.

Is there an easy way to hand a curtain of this poly-lead near the driveway aesthetically? An earlier post discussed a barrier fence or some type of natural barrier- maybe you could integrate either with the lead barrier.

Another option is a conversation with the neighbor regarding your problem and see if the barrier could be integrated into some type of wall (on a 2x2 frame) extending from their garage about 16 feet or so to block your home from direct exposure.

If you already have double pane glass, consider exterior "old-fashioned" storm windows to catch much of the sound before your glass. You could use a foam sealant tape between the window frame and your structure to further enhance quieting.

I am fairly confident that all passive sound damping will be inadequate. What you need is active damping with a microphone/amp/sub-woofer in your bedroom.

The microphone has to have exceptional low frequency response or it will not detect the chest-thumping; perhaps very small woofers (drivers) or high quality headphones can be a low-cost substitute for this microphone. Use drivers with a soft cone suspension. Create a sealed enclosure with a pinhole for atmospheric pressure equalization. If you mount two drivers on opposite sides of the microphone enclosure and connect them in series, they can cancel out motions/vibrations of the enclosure so it is not amplified. Of course, do not set the microphone on the sub-woofer, or any surface that rattles it.

Many commercial sub-woofers will not reach the low frequencies required to cancel this noise, so I recommend using an IB subwoofer design: http://home.comcast.net/~infinitelybaffled/. This "pumps" the noise from your bedroom elsewhere - such as the basement, attic or neighboring room. It also reduces the cost of the sub-woofer to just the drivers.

The power amp may need DC coupling (no capacitive coupling). Keep the volume/gain low enough to avoid positive feedback. Your feedback polarization needs to be negative overall. (At low gain, nudging the microphone membrane in should cause the woofer cone to also go in.) When the polarization is correct, the volume control can be set much higher without causing positive feedback. Be sure to use conservatively rated (smaller current) output fuses to protect the amplifier and sub-woofer. The volume control should be protected: covered or taped in position.

If the amp has enough power and the sub-woofer has enough compliance, you should be able to reduce the rumble by well over 8 DB. It will not cancel high frequencies. That must be handled by dampening or mass (Another layer of sheet-rock). This noise canceler may respond to other low frequency events like the furnace fan, slamming doors, etc. Be sure this does not damage the sub-woofer.

Perhaps your noisy neighbor should cover your costs for this electronic remedy. I would suggest exploring legal / civil recourse. What are the local ordinances? You need to document/record the disturbance (decibels,date,time,duration) and may need to provide impartial witnesses or other neighbors testimony.

Good luck with that idea.

Small rooms are extremely modal in the low frequency region and placing a sub in the room will most likely just increase the problem.

You place the microphone near the bed...

The mic is not the problem. The room is.

With small rooms (smaller than theaters, concert halls, etc.) the lower end of the audio frequency (below 200 - 300 Hz) exhibits extreme modal behavior where phase cancellation and reinforcement rule the behavior of the transducer's sound pressure level.

The worst case is from a single point (monopole) source.

This is two frequency sweeps of my room in slightly different mic locations with a speaker that is flat to almost 30 Hz (actually the F3 point is -3 dB at 30 Hz). However, notice the variation in the low frequency range between the two locations.

You can mitigate this response by placing multiple subs in random positions in the room, but the cost is going to be an issue and it will require a lot of experimentation to get it right.

Experimentation is going to be a problem. First, the source of the noise is only active for a short period of time. So when it goes off you need to make adjustments, hop in bed, and see if it worked. Not an easy task to get fixed.

Second, when the source of the noise moves outside, so does the modal pattern of the source within the room. The windows are the significant transmission points and you have the vehicle moving past each window, which changes the point of entry.

All-in-all, this is an expensive and laborious way to solve a problem.

The cheapest way to fix this issue is being neighborly and trying to negotiate a solution with the neighbor that does not require radical room treatments or hundreds of dollars of electronic equipment to quell the noise.

Frankly, if my car was causing my neighbor to loose sleep I would make every reasonable effort to fix the problem. If the original poster tries to approach the neighbor politely and asks for help with the problem, a reasonable person would make a good faith effort to find a solution.

Next steps might be through legal channels.

However, this is an engineering forum and I fully understand the appeal of trying to come up with clever and ingenious (and sometimes nefarious) ways to solve the issue.

I'm a little perplexed! If you and your neighbor live in a residential neighborhood what is he doing there with a truck that size anyway? He's the one making the noise. Call the code enforcement bureau and have THEM deal with it. Treat the cause; not the symptoms! L.J.

I have built a dozen studios for teachers giving music lessons.

Cork is your best agent. The thicker the better. No parrell walls and te ceiling should slant

There are numeros books on sound proofing

In my office, I played a radio with classical music to drown out noises. After a while, you never hear the music

PEbobimm

Earplugs?

I have built a lot of studios and low frequency sound isolation is the most difficult to do (apart from soundproof air-con systems).

Extra layers of plasterboard (drywall) will do little if fixed directly to the structure. Doubling the mass of a wall will only give 5 or 6dB improvement. However if the new layer is mounted resiliently to form a second independent wall, it will have a significant effect.

You must have enough space and passive absorption material between the two wall to prevent diaphragmatic coupling between the walls which will significantly reduce the effectiveness. In the UK you can buy a plasterboard product with a 1/2" board bonded to a rock-wool board which is glued to an existing wall. I have successfully used the version with 2" of rock-wool and an extra layer of plasterboard to build it up to 1" plasterboard. I sorry I can't lay my hands on the performance figure s right now.

This approach is very effective, but you soundproofing is only as good as the weakest link so it will not be effective unless your floors, ceiling, windows, door and air-con are soundproofed to the same standard.

For a ceiling, plasterboard on resilient hangers with rock-wool behind will work. Windows need heavy glass with wider than usual air gap with an acoustically absorbent lining around the reveal.

Probably your windows are the weakest link. Soundproofing the doors and air-con is too big a topic to cover here.

Cork lining will do little or nothing to prevent external sound coming in. It just absorbs sound within the room, but not low frequencies.

Double glass window is common solution for these type of noise. There are three glass based window and frond door are commonly used to insulate sound from plane. Coconut hard shell powder based paste also helps. This was developed after lead is banded

When I was in high school, we tried the potato in the school bus, but it just blew out. Then we put in about 6 inches of gravel, and bent the edges of the tailpipe with a rock to keep the gravel inside. You could hear it hissing for at least a mile. I understand the gas mileage was very bad until they found the problem. This was food for thought, not a suggestion.

In addition to double glass windows, heavy curtains should help. If you think it's coming through the walls, then brick veneer would help.

Thanks to one and all for such excellent and varied suggestions. I'm sorry for a delayed response, but I only get to do this at the start of my work day.

Rorschach has helped in understanding the problem. I'm in a college town in Texas. Rorschach is exactly right about pickups being the unofficial vehicle of Texas. (No shock to me -- I'm native Texan.) And pickup trucks that have this low loud rumble are all over the place here -- many much louder than his. Expectations of the police (or other authorities) doing anything about are probably pretty slim. And I have spoken to my neighbor... not specifically about being disturbed every morning but I called him on the Friday after last Thanksgiving to let him know I didn't appreciate being woken up by his truck at 4:00am the day after Thanksgiving. To which he replied that he and his wife had to get up that early to beat the shopping lines for the big sales!!?? Since it isn't uncommon for people to park one or more of their vehicles on the street, I suggested he might want to part that truck (he has 2) on the street so when he fires it up it wouldn't cause noise right at my bedroom. He said he'd consider it. Result - the truck is always in the drive. His wife actually drives this truck... he drives his other one; which by the way is quiet.

Basically, even though people who own these trucks are being inconsiderate of their neighbors, you're still asking them to get rid of something they obviously find pleasure in. And these are not young people. The man is obviously around 60. His wife is younger but probably late 40's to early 50's. I understand younger people wanting a "hot rod sounding" truck. That's hormonal -- I don't mean normal. But at their age you would think they would be past that sort of thing and also realize it's a nuisance.

I have tried ear plugs, but they're pretty distracting also. The best thing that has helped so far is to run a box fan pretty loud which helps mask the sound and also helps with air movement in the room. I need it pretty cold at night to get good rest, also. But nothing so far, can compete with this particular noise. Most solutions require spending money so, for one option, I'm considering installing a window air-conditioner thinking it's noise would help mask the truck noise.

I appreciated the humor in your responses, too. A couple of months ago I contacted a local sound studio, thinking they might have some expertise in this and the first thing the guy I spoke with said was, "Go over at night and slash a couple of tires... maybe he'll get the message." Of course, he was saying it, tongue in cheek, as were posters here, but many understand the feeling and the anger it can cause... and therefore the response we'd like to make, if society permitted such things.

I'll investigate the links provided by everyone. And when I implement something, I'll come back to this thread (I've bookmarked it) and let you know how well it worked. (Early on, I had also thought I'd just offer to buy his truck for a good price with the stipulation that he replace it with a quiet truck.)

Later, everyone.

fight fire with fire? borrow a truck... wait till him and his wife are asleep...

To much hassle, use a bass canon instead push out about 18Hz - 25Hz in a manner of fluctuating db levels but be careful they may become physically ill; bummer

You will forget all about the noise if you get into a war with him, that never ends well. I'm in North Carolina, same deal, people spend good money to make their trucks louder, I don't get it. I just found out recently that Harleys come out of the factory quiet. I think there are a lot of people that are so insecure, noise is the only way they can find to get attention. Wish this was more help. Do you have a bedroom on the other side of the house?

If you want to offer to pay for anything, why not offer to pay for a quiet muffler?

"The best thing that has helped so far is to run a box fan pretty loud"

If the fan noise helped how about a white or pink noise generator?

As the guy's wife is the one who actually drives the truck, perhaps you should consider appealing to her "feminine side" by presenting her with a nice bouquet of flowers (A nice bunch of snapdragon's or nightshade would do) and a envelope containing two tickets to the Jerry Springer Show, or an offer to show her your tattoo of Willie Nelson.

I am not a lawyer, and I don't play one on TV either, but I know a thing or two about the law and I'm about to give you some good legal advice:

If you live in a subdivision that has a home owner's association, you should try to get them involved concerning the noise issue as well. DOCUMENT it. Send all letters certified mail with return receipts and keep copies of everything. Send certified letters to him as well and again keep records and copies of everything.

Whether you believe the cops will do anything or not, make a complaint every time it happens. They HAVE to take your complaint, even if they do nothing.

All of this builds a documentation record that you can then point to in a court of law when you sue him. That you have tried numerous times via numerous avenues to alleviate the situation and you continue to have the value of your property reduced and the enjoyment of your property infringed by your neighbor's repeated violations of the noise ordinances.

This is not good advice. People that pay HOA dues do not have a neighbors driveway outside the bedroom window. You have obviously never lived in a low rent district, no offense to the OP. Repeatedly calling the cops will get him killed. The cops themselves will tell you, there is nothing we can do until an actual crime has been committed. While this may be good legal advice, it is in no way grounded in reality.

sorry I have to call BS. I happen to live in a neighborhood with just such an HOA and my neighbor's driveway is four feet from my bedroom wall. we don't have zoning laws down here, that is what HOA's are for. virtually every subdivision has just such an HOA.

My bad. You're getting ripped off my friend. If you are paying HOA dues, is this situation not exactly, what the HOA is supposed to either prevent or put a stop to. What the hell are you paying dues for? The little mound of shrubs at the entry? You just said my post is BS, and that this is what HOA's are for. Where the hell are they? Why is this guy coming here for answers? You might want to jump off the computer and ask this question of your own HMO. Where is the money going? Where is my representation? Sorry to ruffle your feathers, but, these are valid questions for anybody that pays into an HOA to ask. I'm sorry if I offended you, but I have to stand by my previous post, antagonizing the neighbor by repeatedly calling the cops is a no win situation.

Is that not exactly what the neighbor is doing to the OP? constantly irritating and pissing off the OP after being told his pipes were too loud and that it was disturbing his sleep? I'd say that live and let live has left the building here a long time ago. You have to report it to an HOA usually before they will take notice. How would they know he's waking you up with the pipes otherwise?

HOA's are a good example of democratic rule what a mess except in the small associations; less than fifty units or owners even then it can be perplexing. Get a vial an empty stink-um vial, the odor-ant used for natural gas an break it in the pickup bed an they'll park it on the street guaranteed .

We are in total agreement, report it to the HOA, if talking to the neighbor doesn't help. The HOA then has an obligation to do something about it. If the HOA decides to ignore the documented complaint, then the HOA itself has opened itself up to a lawsuit. Most HOA's, even in Texas have noise ordinances. The OP's problem would no longer be with the loud neighbor, but with the HOA, which is its own entity and is fraudulently collecting his dues, and not enforcing their own rules. What the other poster was recommending, essentially amounted to calling the "police" every time the neighbor started his truck. IMO this would not only anger the neighbor, but the police as well. If he is indeed in an HOA, they have a legal responsibility to take care of it.

kramarat I believe you failed to notice the order of operations, we are in agreement that getting the police involved is a last (well nearly) resort:

step one: send a certified letter to the neighbor noting the problem and offering to work with the neighbor to come to a mutually acceptable solution, but point out that if a mutually acceptable solution cannot be arrived at you will be forced to take further steps to alleviate the problem. keep copies.

if step one fails, step two would be to notify the HOA. It might be a good idea to set up an SPL meter at your window with a video camera pointed at the meter do document the sound level. provide a copy of the video to the HOA as evidence of excessive noise levels. Also if it is a rental and not a homeowner, contact the owner (by certified mail, again keep copies) and raise hell with him before contacting the HOA if there is one.

If step two fails, THEN get the police involved, provide them with copies (NOT ORIGINALS!) of your documentation and hopefully they will issue him a citation, or at least a warning. At that point the neighbor MAY do one of two things, they may recognize that the issue is a serious one and change his behavior, or he may get pissed off and start causing trouble, call the cops every time he acts up and threatens you or damages property. get a CHL and arm yourself if you feel that he may become violent (better safe than sorry).

Different locations have different nuisance laws but here in Houston, if three complaints are made within a certain time period, you can actually have the property seized if the nuisance is not abated. Not saying you should do that, but it is one option.

If the police have been unable to get through to him, a lawsuit, usually in small claims court, is the next option. even though you do not need a lawyer in small claims, you would do well to obtain one anyway. a person who acts as his own lawyer has a fool for a client.

I am not trying to disagree with you. The only comment I took issue with, was filing a complaint with the police every time the truck is started. In a perfect world this might help, but in the real world, most of the cops probably have loud trucks themselves. Let's agree that we are both after the same thing, helping the OP get some peace and quiet, and since we are veering way off topic here, maybe we should leave it at that. No offense taken and hopefully none given. I hope everything works out for the guy. Have a good one.

I vote for Chankley's answer. Also, I hope I can offer a few supplemental comments about some points brought up throughout this thread:

• It's not about density. It's about mass. There are less expensive and safer sources of mass than lead. 5/8" drywall for example.
• You can't seal heavy curtains
• Windows are indeed the weak point of the typical wall. Laminated glass is used in acoustic environments. Look for a soundproof window that uses this.
• Standard fiberglass works as well as anything IN a wall or ceiling. http://www.nrc-cnrc.gc.ca/obj/irc/doc/pubs/ir/ir761/ir761.pdf
• Heavy Mass Loaded Vinyl is simply another source of mass. That's great, but much more expensive than standard drywall. Mass is mass.
• Damping mass with one of various damping compounds is a great idea.
• Absorptive panels won't stop low frequencies.
• Cork is rarely used anymore. It has very limited use in floors at this point.

Certainly not looking to ruffle feathers, but its common to find some mis-information about sound isolation.

The NRC is the finest acoustics lab in North America.

At one time my sleeping area was directly under a steel runway for jets the noise was horrendous if not the roar of turbine engines then the slam to deck of landing aircraft and the sound of cables rapid unwinding then growling rewind ending with a sharp whack-w-whack-whack upon the deck when taut again. Having returned to sea from several years in the north woods I needed significant relief so I lined the area immediate to the rack with corrugated baffles designed to mitigate sound from escaping old type data processing centers and added a sound deadening curtain. But I over did it it was freaky not being able to hear my heart beat .

The frequency of the exhaust actually isn't that low, I suspect not less than 32Hz. Now the first thing is use an SPL meter to ascertain the frequency levels needed to block or reduce.

Reply with audio level info, construction materials used in the structure and the distance from the driveway...and is there other structure on the other side of the driveway?

Its an upbringing thing, in the RN I used to sleep about 20 feet away from a twin 4.5" Turret, and I've slept through class A shoots no problem.

On a ship, you only wake up if they get a power failure and the fans go off!! Then its eerie quiet!!

Eerie quiet and the motion is strange...motion is not noticed quite the same on an aircraft carrier as on the smaller ships and that's what I prefer. I recall walking about fairly easily during typhoon when on CV63 as is were normally rolling conditions aboard a 450' ship

For all the time an money required to mitigate the OP's dilemma I'd construct a sleeping chamber instead.

Have you tried the Egg Carton trick?

Kinda cheesy, but cheap, putt the egg holder part of egg cartons all over the wall, hang some heavy curtains over the windows.

I've seen folks do this for some homemade studios......

Sorry, egg cartons are irrelevant to this problem.

There are 3 issues that to be dealt with in room acoustics:

1. Isolation - keeping unwanted sound out and keeping sound in that would disturb others.
2. Absorption - controlling the reflections within the room to prevent it from being too live.
3. Diffusion - controlling the reflections to produce a diffuse sound from all around , without dominant reflections, echos or resonances.

These have all have too be controlled consistently across the entire audio spectrum.

Unfortunately these issues are frequently confused and there is a great deal of misinformation written about them, even in semi-professional circles.

make sure that 'rumour' about your military training leaks out... navy seal, special forces... perhaps the problem will fade away...

Cover you walls,Interior or exterior with "Dryvit." It'll do what you want.