Transmitting sound to neighbors, which bass frequency is most audible for these neighbors?

[DanielT]

Scenario. Thin walls, sound transmitted between neighbors' apartments. You know how it can be. You have all, those of you who have ever lived in an apartment, experienced this. More or less experienced it depending on the construction of the house of course but it exists as you know.

Then the question is. Intuitively I thought the lower the frequency the worse, or more sound transmitted, but it is mostly bass rumbling down towards and around 20 Hz. Isn't bass around let's say 50 Hz-80Hz more audible and potentially more annoying? Because it's the annoying aspect that matters. Maintain the good neighborly relationship, be considerate and so on. Having said that. Generally about acceptance between neighbors, the neighbors also need to be able to accept that there is noise in an apartment complex. That's just the way it is. Note that this is a separate question that is more related to sociology, I am most interested in the acoustic effects, the phenomena, how it works with bass transmission between walls, apartments.

 

[capslock]

I would assume that lower frequencies get transmitted better. Just look at how an absorber of say 10 cm works only down to a certain frequency. So if the 20 Hz are eq'd to the same audible level as the 60 Hz (which is a stretch, I believe most people do not hear 20 Hz but really the harmonics, and I suspect all the old research on hearing thresholds was done with woofers that generated plenty of harmonics), it will be transmitted more through drywalls and wood ceilings with rockwool filling.

Now, for purely concrete and brick buildings, there is no porous absorber. It is about mass and depends most on where the resonances are. Again, I would assume lower frequencies to consume less energy because the vibration is slower.

The key to having bass not transmit is do go away from pressurized bass. This means either dipole bass or DBA (double bass array).

Double bass array - Wikipedia

en.wikipedia.org

 

[DanielT]

I found some posts where an acoustics consultant talks about exactly what I'm wondering about:

I-or:
For normal single-wall concrete structures, the airborne sound insulation shows a fairly constant level in the stiffness-controlled area below about 80 Hz, and all mid- and low-bass sound passes through the wall with about the same efficiency. However, there is also the sensitivity of hearing, which decreases rapidly with decreasing frequency (about 20 dB/octave below 60 Hz at the sound pressure levels that are roughly involved here).

If for some reason you only play real low-bass below 40 Hz, you will therefore be able to push it quite hard before disturbing the neighbors. Most people probably already have an intuitive understanding of this, since the "thud" around 60-100 Hz is clearly the most audible and disturbing, while the low-bass sound is rarely heard at all (although this is quite natural, since it is also relatively uncommon).

In a slightly more modern apartment building, which usually has significantly higher sound insulation, not least to accommodate various sound systems, you don't need to worry too much overall if you stay within moderate sound levels regardless of frequency content. However, in the late evening and at night, the background level in the apartments drops and many people also become more sensitive to sound, which is why you should be quite careful.

I would think that film sound for the same peak levels is usually significantly less disturbing than popular music with its rather monotonous grinding. It is significantly more difficult to separate the sound effects from the background noise than music and for example a really heavy sound effect of 115 dB in the listening position at 15 Hz is inaudible on the other side of a concrete wall, as the hearing threshold is around 80 dB here (despite the fact that the sound insulation is significantly higher around 500-1000 Hz, the neighbors are probably most disturbed by slightly more mid-frequency sound excesses such as various crashes and bangs since both the hearing threshold and above all the background level are lower here). In addition, of course the sound levels are only high in relatively limited parts of the film even for action movies.

Incidentally, the facade insulation below 100 Hz is lousy in normal wooden structures for single-family houses and it can be heard quite clearly indoors in my house when the neighbor is blaring music 20 meters away (which is extremely rare). The only thing that is genuinely annoying are idiots who don't have the sense to close the door when playing music or in the summertime move their crappy Bluetooth speakers outside to contribute to maximum noise reduction and also demonstrate their terrible taste in music to the entire neighborhood. In my youth, however, I used to play without open doors or windows with my properly sound pressure-capable Cerwin-Vega speakers so that it could be heard quite clearly outdoors over 100 meters away, but that is outdated.

From the thread:
More stupid questions: Does deep bass affect neighbors?

faktiskt.io • Visa tråd - Mera dumma frågor: Påverkas grannar av djup bas?

 

[staticV3]

I'm a do it once, do it right advocate.

I'd prepare some test tones, then ask them kindly to, at a time least bothersome to them, be able to listen to them from their apartment.

It's to reduce noise disturbance, which they can surely get behind.

You can use something like Chrome Remote Desktop to control your computer remotely and play/pause the tones.

 

[Count Arthur]

Sadly, I think the only solutions are expensive, or be quiet.

You can help by decoupling speakers or sub-woofers from the floor. I changed the hard feet on my subwoofer for these:

SVS SoundPath Subwoofer Isolation System | No Rattle, Better Bass

Reduce rattle and improve subwoofer bass with the SVS SoundPath Subwoofer Isolation System. Universal pad feet work with any brand or model.

www.svsound.com

IsoAcoustics also make a whole bunch of platforms and feet:

IsoAcoustics | Award Winning Audio Isolation Products

Award winning audio isolation products. Hear perfect sound from your home audio or pro audio setup. Isolation solutions available for a variety of Home Audio applications. Allowing music enthusiasts to experience a higher level of clarity and openness. IsoAcoustics Home Audio products combine...

isoacoustics.com

Beyond that, there are more thorough, but expensive solutions:

How to Keep Bass From Going Through Walls

Here are ways you can keep or greatly reduce bass music from coming through your walls. We include materials, installation and some other tips and tricks.

bettersoundproofing.com

 

[DanielT]

I would assume that lower frequencies get transmitted better. Just look at how an absorber of say 10 cm works only down to a certain frequency. So if the 20 Hz are eq'd to the same audible level as the 60 Hz (which is a stretch, I believe most people do not hear 20 Hz but really the harmonics, and I suspect all the old research on hearing thresholds was done with woofers that generated plenty of harmonics), it will be transmitted more through drywalls and wood ceilings with rockwool filling.

Now, for purely concrete and brick buildings, there is no porous absorber. It is about mass and depends most on where the resonances are. Again, I would assume lower frequencies to consume less energy because the vibration is slower.

The key to having bass not transmit is do go away from pressurized bass. This means either dipole bass or DBA (double bass array).

Double bass array - Wikipedia

en.wikipedia.org

Sadly, I think the only solutions are expensive, or be quiet.

You can help by decoupling speakers or sub-woofers from the floor. I changed the hard feet on my subwoofer for these:

SVS SoundPath Subwoofer Isolation System | No Rattle, Better Bass

Reduce rattle and improve subwoofer bass with the SVS SoundPath Subwoofer Isolation System. Universal pad feet work with any brand or model.

www.svsound.com

IsoAcoustics also make a whole bunch of platforms and feet:

IsoAcoustics | Award Winning Audio Isolation Products

Award winning audio isolation products. Hear perfect sound from your home audio or pro audio setup. Isolation solutions available for a variety of Home Audio applications. Allowing music enthusiasts to experience a higher level of clarity and openness. IsoAcoustics Home Audio products combine...

isoacoustics.com

Beyond that, there are more thorough, but expensive solutions:

How to Keep Bass From Going Through Walls

Here are ways you can keep or greatly reduce bass music from coming through your walls. We include materials, installation and some other tips and tricks.

bettersoundproofing.com

You can build extra interior walls to soundproof. But it takes time, costs money and you reduce the area of a combined living room, listening room.

Anyway. I live in an apartment complex where sound unfortunately is easily transmitted between the apartments, BUT in practice I am lucky in that I have nice, fairly sound-insensitive neighbors. I also don't really care when, for example, the students who rent an apartment below me sometimes start their weekend disco. Then it's just for me and my neighbor across from me to playing music at high volume.In a way, a green light for a little higher volume in the apartments, so to speak.Pretty nice I must say. To a certain extent and not to late in the evening of course because there are several other neighbors in the house.
The main rule in Sweden is that apartments should be quiet between 10 p.m. and 7 a.m. Everyone must respect this.

I was most interested in the acoustics regarding bass transmission between apartments themselves.

Edit:
If you live in an apartment with thin walls, easily transmitted sound, and want to listen to bass-heavy music at high volume while having very easily irritated neighbors, the only thing left is this:
(Not my case, easily irritated neighbors that is)

 

[DanielT]

I'm a do it once, do it right advocate.

I'd prepare some test tones, then ask them kindly to, at a time least bothersome to them, be able to listen to them from their apartment.

It's to reduce noise disturbance, which they can surely get behind.

You can use something like Chrome Remote Desktop to control your computer remotely and play/pause the tones.

It is a practical solution, or test if the need exists. For that you need what the Germans call Fingerspitzengefühl.

Fingerspitzengefühl [ˈfɪŋɐˌʃpɪtsənɡəˌfyːl] ⓘ is a German term, literally meaning "finger tips feeling" and meaning intuitive flair or instinct, which has been adopted by the English language as a loanword. It describes a great situational awareness, and the ability to respond most appropriately and tactfully. It can also be applied to diplomats, bearers of bad news, or to describe a superior ability to respond to an escalated situation. The term is sometimes used to describe the instinctive play of certain football players.[1]

Fingerspitzengefühl - Wikipedia

en.wikipedia.org

Psychologically Fingerspitzengefühl that is. Because even if you say you are doing it to show consideration for your neighbors, they can perceive it as if you are irritated with them and that you are doing that test as a mark. A mark, a subtle hint that you think they should be quieter. They can perceive it that way even if you say that is not the case.

 

[staticV3]

It is a practical solution, or test if the need exists. For that you need what the Germans call Fingerspitzengefühl

Fingerspitzengefühl - Wikipedia

en.wikipedia.org

Psychologically Fingerspitzengefühl that is. Because even if you say you are doing it to show consideration for your neighbors, they can perceive it as if you are irritated with them and that you are doing that test as a mark. A mark, a subtle hint that you think they should be quieter. They can perceive it that way even if you say that is not the case.

That's where honest and sincere communication comes into play

For example, you could tell them that, even after you've adjusted your system based on what you heard during the test, if at any point the noise becomes too much, they can reach out and you'll readjust your system.

Communicate to them that you're looking for a solution that works for both parties and I'm sure they'll understand.

On that front, consider looking into bass shakers to compensate for reduced sound pressure.

Done well and in moderation, shakers can be super nice.

 

[ZolaIII]

@DanielT it's about getting vibrations down. You can make feats from aluminium candle hosting feeling it with silicone and putting a dime or something else in the middle. Magic? There's none, fendamental of material is 19 Hz. Neighbors will still be able to hear it but it will be much more less annoying and it's not only about the neighbors but also people you live with. Rest depends upon them and even if they accept it most of times they won't be like that always.

 

[Thomas Savage]

I feel for the OP , I chose to physically put my hifi on and visit the neighbours , also stand outside the house .

I simply could not relax while thinking I'm disturbing others .

But , what about low bass , can't these mature or peak some distance away from source ? So is it not possible a bass note might mature in a neighbours lounge while being silent elsewhere? Iv always slightly worried about that , well .., a few beers tends to dull that anxiety.

These days its seems folks are perfectly happy to play audio on their phones while on the train or play music in their gardens so , very different times we live in .

 

[Mnyb]

yes you have the fletcher munson curve over what we can perceive and the actual bass content in music and soundtracks it's getting messy very fast .

But ill would guess that the lowest frequency actually are the least annoying the punch and rythm of your music is not there so low and mid bass is most problematic .
No techno for you

I would also guess that doing due diligence with room correction helps a lot if you are reducing peaks by 10dB it's not only for you
I would further guess in building with similar apartments the neighbor might have a room with exactly the same resonances , the "same" room might be both upstairs and downstairs from you ? But this is a bit of conjecture ...

 

[Willem]

I would also guess that doing due diligence with room correction helps a lot if you are reducing peaks by 10dB it's not only for you

This would be my first step. Room modes can produce nasty peaks, Tame those, and you have solved half the problem.

 

[DanielT]

I thank you all for your help, suggestions and advice.

Actually, for me it is an adaptation phase. The prerequisites are thin walls BUT nice flexible and not (as far as I know) sound-sensitive neighbors. They play music and connect their home theater systems and so on so it is not a quiet apartment complex, which suits me well. Having said that, if you live in an apartment there are limits to what you can do before irritation occurs, no matter how understanding neighbors you have.

Listening to music is not really a problem for me. I can listen to music at a modest listening volume, let's say around 65 dB for hours. It is also no problem to sometimes, for shorter periods of time, turn the volume up quite a lot. No sour faces from the neighbors, no hints and so on that they would be irritated. But okay, if there are solutions that isolate the sound, I will not say no to that. It would be nice to have, but if it doesn't work out, it's not the end of the world.

I used to live in the countryside in a house quite far from the nearest neighbor, so this sound level was not something I thought about. I also played at a modest listening volume then, but with the difference that I sometimes played at a really high volume for a long time. I can't do that now. Incidentally, it didn't come as a surprise. I've lived in an apartment before, so I know how it works. However, I've never lived in an apartment with a this amount of sound transmission. That was a surprise, I must say.

It's also good for the wallet. No point in spending money on an expensive high-capacity SPL system if you can't use it.
I said that with a bit of bitterness in my tone. Not much but a small bit of bitterness is there I must admit.

I understand if what I said above sounds a bit contradictory and schizophrenic but it's just that it's not black or white.It's a gray area.

 

[Speedskater]

In olden times, the AVSforum 'Dedicated Theater Design and Construction' section and almost daily posts on this subject.

https://www.avsforum.com/forums/dedicated-theater-design-construction.19/

 

[edechamps]

You may want to check out this older thread and my reply to it: https://www.audiosciencereview.com/...-in-an-apartment-building.36230/#post-1270172

 

[hex168]

If you put a dipole sub close to you, it's output near-field is much higher, but total energy into the room is low.
Dipoles up close:

Dipole on axis

Try one of these 15" in a frame right in front of you (maybe a foot-rest?) or behind you:

mfk-projects MCM woofers

inexpensive woofers from mcm electronics

www.mfk-projects.com

https://www.newark.com/mcm-audio-select/55-2974/15-woofer-with-poly-conerubber/dp/80R7013?st=15

https://www.newark.com/multicomp-pro/55-3234/200w-rms-4-ohm-rubber-surround/dp/43W7875?MER=BR-MER-PDP-RECO-STM72194

Per MFK, the advertised Q is wrong; the skimped magnet leads to a Q close to 2. For a dipole, that's a feature, not a bug!

I've always wanted to do a design for desktop listening where I build a dipole woofer into the back panel of a desk, right in front of the listener's knees/shins/feet. Another retirement project, alas.

 

[DanielT]

If you put a dipole sub close to you, it's output near-field is much higher, but total energy into the room is low.
Dipoles up close:

Dipole on axis

Try one of these 15" in a frame right in front of you (maybe a foot-rest?) or behind you:

mfk-projects MCM woofers

inexpensive woofers from mcm electronics

www.mfk-projects.com

https://www.newark.com/mcm-audio-select/55-2974/15-woofer-with-poly-conerubber/dp/80R7013?st=15

https://www.newark.com/multicomp-pro/55-3234/200w-rms-4-ohm-rubber-surround/dp/43W7875?MER=BR-MER-PDP-RECO-STM72194

Per MFK, the advertised Q is wrong; the skimped magnet leads to a Q close to 2. For a dipole, that's a feature, not a bug!

I've always wanted to do a design for desktop listening where I build a dipole woofer into the back panel of a desk, right in front of the listener's knees/shins/feet. Another retirement project, alas.

Thanks for the tips.

What a coincidence. Just when you posted your post, I remember what Floyd Toole wrote about subwoofers in his listening room. It was partly about aesthetics, but also about subbass sound. This, page 20, #381:

Here is Floyd Toole's listening room:

Floyd Toole:
I have recently relocated from sunny Southern California to my old home of Ottawa Canada, leaving behind my superb home theater in a stand-alone house, and moving into a luxury condominium that better fits the life style and needs of an 86 year old. The room is smaller, 13 x 18 x 8 ft, the largest I could carve out of the allocated 2400 sq ft we now have. Being in a condo, sound transmission to our neighbors is a concern, so cinema sound levels are not possible (even 10 inches of concrete convey low frequencies) so I wanted subs with minimal mechanical vibration (opposing woofers) and small enough to be able to be located where they minimally energize room resonances. From prior experience and the Todd Welti modeling of passive multi-subwoofer solutions in rectangular rooms (which this is) it was clear that one of the best arrangements is to place subs 25% of the way from the walls - front, rear, and sides. In a small room this also places the subs close to the listeners - in the near-field - which is a second advantage to keeping room sound levels down. I had previously used Sonos subs in a second background music system and was impressed by how good they looked and how easy they were to place, but when looking around I discovered that one of my old Canadian manufacturing colleagues, Paradigm, had their Millenia subwoofer that seemed as though I might be well matched to my new purposes. The system is yet to be equalized, but with just two of these subs, located in very unobtrusive locations, the bass was surprisingly good - impressive in fact. A photo is attached, showing the sub tucked in on each side of a sofa. Room modes are very subdued, especially the side-to-side (lateral) modes, as theory would predict. The first order length mode is still in evidence, notably when one moves from the front seats to the rear seats, so I may well purchase two more to be located at the front of the room - I'll see what measurements and EQ can do first. My processor this time is not an elaborate Trinnov based unit, but an Anthem AVM-90, again from my old NRCC day colleagues. It has what is reported to be an effective EQ scheme.

So, depending on your room, lifestyle, and living circumstances, a little lateral thinking may provide more alternatives to the knee-jerk locations against walls, using rectangular box subs. A single monster sub is not a good solution for anyone. Multiple subs can be smaller - there are gains in efficiency.

Totem Acoustics Rainmaker Speaker Review

Also add the interior design challenge of having multiple subwoofers in a combined living room, listening room. Subwoofer cubes are not particularly beautiful. Which can be exemplified by the thread linked below. Currently; 227 pages with 4537 posts...

audiosciencereview.com

 

[edechamps]

In my experience, using a subwoofer near-field comes with its own problems: small differences in listener position results in wild variations in bass level, and it can be awkward as the parts of your body closer to the sub "feel" more bass than the parts further away. I've tried it once and really didn't like it - I ended up repositioning the sub further away.

 

[617]

Proximity is the best solution. The idea that since we are less sensitive to bass, it somehow is less of an issue for neighbors is absurd - since we are less sensitive, we compensate with 15" woofers with huge xmax and boosting the levels so we can hear them.

Don't try to control the emission of LF, the best you can do is get it near your head and turn it down. Remember every halving of distance means you can turn it down 6db. The extreme case is headphones, where you can play as loud as you want without anybody noticing.

We are moving away from single-family detached housing in many areas, so the era of big cheap speakers is likely over.

 

[DanielT]

I did a quick google search and found this. This is for US, but similar rules for other countries most likely exist. Rules that didn't exist when they built my apartment complex:

Design and Building Codes​

For newer or remodeled multi-family dwelling units, the various Building Codes throughout the United States require a measure of sound insulation between floors of multi-family dwellings. The Building Codes specify a minimum architectural design standard of privacy of 50 STC (Sound Transmission Class) and a 50 IIC (Impact Isolation Class). The Building Codes also state that validation of the minimum noise criteria can be field measured and the field measurements shall not be less than a 45 FSTC or a 45 FIIC. While some community building inspection departments require field-testing to be conducted before a certificate of occupancy is issued, many, if not most, do not. They rely instead on the architect’s specification and acoustic design recommendation and the expectation that their specified designs will result in the minimum sound isolation construction between adjacent units.

Noise Control in Multi-Family Buildings | Residential Soundproofing

Get expert tips on soundproofing multi-family buildings from Acoustical Surfaces. Improve noise reduction and enhance quality of life for residents. Learn more!

www.acousticalsurfaces.com

Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. In the US, it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. Outside the US, the ISO Sound Reduction Index (SRI) is used. The STC rating very roughly reflects the decibel reduction of noise that a partition can provide. The STC is useful for evaluating annoyance due to speech sounds, but not music or machinery noise as these sources contain more low frequency energy than speech.[1]

Sound transmission class - Wikipedia

en.wikipedia.org