Do room modes annoy neighbours?

[Curvature]

So you're saying the modes don't act as an amplifier for what's being heard on the other side?

Exactly. Maximum pressure is at the walls, which is where transmission takes place, not around the room where modes are distributed.

 

[kemmler3D]

As far as I know modes are caused by internally reflected sound in the room so what you hear due to modes isn't what your neighbors will hear.

On a practical level my approach to subs+ neighbors is to turn them off after dark, or at least at a very reasonable hour. I have 4 subs in 2 setups, No complaints so far.

 

[Oddball]

Exactly. Maximum pressure is at the walls, which is where transmission takes place, not around the room where modes are distributed.

It could be around the room as well, ceiling is also a wall. I have difficult time reading the chinese cookies so would appreciate none to deal with.

 

[Curvature]

It could be around the room as well, ceiling is also a wall. I have difficult time reading the chinese cookies so would appreciate none to deal with.

You're saying my posts are too cryptic?

Ok. Any boundary will represent maximum pressure. In that sense it corresponds to the peak on the opposing boundary and the antinode (dip) exactly between the first axial modes, located in the "middle" of the room. The wall will then flex and vibrate, transmitting sound to the other side. When you are walking around and hearing modal effects, or measuring them, these have no bearing on the transmitted sound.

 

[FireEmblem]

Exactly. Maximum pressure is at the walls, which is where transmission takes place, not around the room where modes are distributed.

Now I'm confused guys. Some say yes modes amplify the energy that goes to the neighbour, some say no they don't.

I mean technically, modes are the result of overlapping reflections, no? So energy is stacking wherever that overlap happens. But since it's reflections that cause the mode, the energy already had to go to and through the walls, and a mode is created from the leftovers.

Logically, I would assume that leftovers don't have as much energy as the first initial waves that came out of a sound source (even though the rumbling sounds much louder), so it shouldn't be able to amplify the rumbling even more when the reflections bounce to the wall once more, since energy dissipates.

Does that make sense?

 

[Keith_W]

When sound impinges upon the wall, particle velocity is zero, and pressure is at maximum. This causes the wall to deflect. Some of the energy is re-radiated back into the room and causes room modes. Some of the energy is radiated to the other side.

Now let us consider two rooms: the first room is a solidly built concrete box with walls a couple of feet thick. The second is a ramshackle thin plywood box. The concrete room walls will barely deflect, nearly all the energy is reflected back into the room. This causes very strong room modes to develop. But your neighbours don't hear very much, if anything at all. The plywood room will deflect like crazy. It radiates less energy back into the room, and nearly an equal amount of energy to the outside. Your room modes will be much weaker, but your neighbours will hear as much bass as you. Your room will be somewhere in between.

 

[FireEmblem]

When sound impinges upon the wall, particle velocity is zero, and pressure is at maximum. This causes the wall to deflect. Some of the energy is re-radiated back into the room and causes room modes. Some of the energy is radiated to the other side.

Now let us consider two rooms: the first room is a solidly built concrete box with walls a couple of feet thick. The second is a ramshackle thin plywood box. The concrete room walls will barely deflect, nearly all the energy is reflected back into the room. This causes very strong room modes to develop. But your neighbours don't hear very much, if anything at all. The plywood room will deflect like crazy. It radiates less energy back into the room, and nearly an equal amount of energy to the outside. Your room modes will be much weaker, but your neighbours will hear as much bass as you. Your room will be somewhere in between.

Wall thickness to one neighbour is 27cm, 38cm to the other. I just measured one from the stairwell and the other from the balcony wall that's separating our windows. Don't know about the floor though..

Material seems to be concrete or brickwork, knocking test on the walls is very hard without any shallow sound.

But the main thing I'm thinking about now is modes vs. actual bass.

So when I use my subwoofer on my consumer system, I know that's actual bass and that my neighbours will hear it because it goes straight into the building.

For the 7" monitors however, the bass sounds much weaker of course. So technically I'd assume that the "real" bass will be much fewer for the neighbours than from the modes.

Like I've thought about that in my previous post, I see no reason why modes would actually increase bass transmission since they're just the product of already reflected soundwaves, leftovers. Maybe someone knowledgeable in that regard can confirm or disagree with this.

 

[RexrothPigeon]

I takes me just a single measurement mistake to completely mess up whatever correction is occuring, that's too hot for me. I would prefer if things just work straight out of the box so I'm seeking a pair of speakers that just suits my room.

you are really missing out. no matter what speakers you use, dsp can provide major, audible improvements

 

[RexrothPigeon]

I have difficult time reading the chinese cookies so would appreciate none to deal with.

what is this supposed to mean?

 

[RexrothPigeon]

Wall thickness to one neighbour is 27cm, 38cm to the other. I just measured one from the stairwell and the other from the balcony wall that's separating our windows. Don't know about the floor though..

Material seems to be concrete or brickwork, knocking test on the walls is very hard without any shallow sound.

But the main thing I'm thinking about now is modes vs. actual bass.

So when I use my subwoofer on my consumer system, I know that's actual bass and that my neighbours will hear it because it goes straight into the building.

For the 7" monitors however, the bass sounds much weaker of course. So technically I'd assume that the "real" bass will be much fewer for the neighbours than from the modes.

Like I've thought about that in my previous post, I see no reason why modes would actually increase bass transmission since they're just the product of already reflected soundwaves, leftovers. Maybe someone knowledgeable in that regard can confirm or disagree with this.

Can't you just go ask your neighbors? Are they extremely scary or something?

 

[FireEmblem]

you are really missing out. no matter what speakers you use, dsp can provide major, audible improvements

I bet it can, if you know what you're doing. If I mess something up during the measurement and the correction does the wrong thing, I'm setting myself up for failure.

Can't you just go ask your neighbors? Are they extremely scary or something?

One of my neighbours is a bit hypersensitive to bass sometimes, and I'm afraid if I am asking him he will either hyper-focus on it and feel more annoyed than before, because I brought it back into his consciousness, or he might use the situation to his advantage and just tells me the bass is too powerful and demands that I tone it down or something.

As of now everything's been fine for months.

 

[RexrothPigeon]

I bet it can, if you know what you're doing. If I mess something up during the measurement and the correction does the wrong thing, I'm setting myself up for failure.

I think you're selling yourself short. I'm a complete idiot and I was able to set it up. Also, if it doesn't come out right, just do it again--it's not like a tattoo or vasectomy.

 

[FireEmblem]

I think you're selling yourself short. I'm a complete idiot and I was able to set it up. Also, if it doesn't come out right, just do it again--it's not like a tattoo or vasectomy.

How do you know it's correct, or that you made a mistake? You may measure wrong, post it here, people don't know you did something wrong, they reply to the measurements only, you set up the EQ, the EQ sounds good, but good doesn't equal truthful, and that's it. I think it's difficult to know whether or not the entire process was successful.

If I use monitors straight up the way they've been designed I know that I didn't touch on what very capable engineers constructed for the frequency response, and all I have to deal with is that my room doesn't throw reflections in my face so that I can hear everything clear and distinguishable.

 

[Oddball]

How do you know it's correct, or that you made a mistake? You may measure wrong, post it here, people don't know you did something wrong, they reply to the measurements only, you set up the EQ, the EQ sounds good, but good doesn't equal truthful, and that's it. I think it's difficult to know whether or not the entire process was successful.

If I use monitors straight up the way they've been designed I know that I didn't touch on what very capable engineers constructed for the frequency response, and all I have to deal with is that my room doesn't throw reflections in my face so that I can hear everything clear and distinguishable.

If your are afraid of a shadow, then you have a problem. You have to live with your neighbours but they also need to live with you.

 

[RexrothPigeon]

all I have to deal with is that my room doesn't throw reflections in my face so that I can hear everything clear and distinguishable.

How do you know it's correct

I think you've answered your own question

 

[FireEmblem]

If your are afraid of a shadow, then you have a problem. You have to live with your neighbours but they also need to live with you.

Don't get me wrong, I'm not walking on eggshells here. My consumer 2.1 system with sub can really hit hard and I listen to music louder or watch movies with a lot of SFX and big soundtracks all the time.

But the mode that the T7V created was something else. That was like a thunderstorm right in my room, as if I was dropping a barbell over and over again. Okay, slightly exaggerated, but certainly it was more punch 'in the air' than what even my subwoofer usually does. If my neighbours don't hear this, I'd be happy and use a 7" monitor, but if they can hear this, that would imo go beyond what I think any neighbour should have to accept.

So it's essential for me to know whether or not modes 'leave' the room, or if they're merely a local phenomenon, a leftover after the reflections did their thing. I'd be happy if I could use the 7" here or another 3-way system maybe with more low-end to save myself the space of another sub.

I think you've answered your own question

Well, that's two different things. What I described means I'm aware that

a) the speakers do what they should, the way the engineers intended it
b) my room isn't adding enough reflections to bother me and impair my mixing

But if I measure my room, make a mistake, and the faulty EQ fixes the bass mode so that it's gone, but introduces other problems, then I just made a step to the side maybe without even knowing.

With the former approach I know that I'm only substracting problems, not possibly adding them.

 

[RexrothPigeon]

b) my room isn't adding enough reflections to bother me and impair my mixing

if you're mixing music, you need to address room treatment, regardless of what's going on with your neighbors. A room mode like the one you're describing is a massive impairment to mixing, full stop.

 

[FireEmblem]

if you're mixing music, you need to address room treatment, regardless of what's going on with your neighbors. A room mode like the one you're describing is a massive impairment to mixing, full stop.

Afaik modes are no problem as long as they don't occur in the listening position. I've read that you'll never get all modes out of a room. In my listening position there's not the smallest smearing of the bass, not even if I tilt the head or move a bit around. It's really just in that one spot. That one is approx 2 metres away from me.

 

[Keith_W]

Like I've thought about that in my previous post, I see no reason why modes would actually increase bass transmission since they're just the product of already reflected soundwaves, leftovers. Maybe someone knowledgeable in that regard can confirm or disagree with this.

Correct. Room modes are in your room. Not only that, but it is also dependent on the position of the observer. What is transmitted to your neighbours is something else entirely.

 

[posvibes]

Don't get me wrong, I'm not walking on eggshells here. My consumer 2.1 system with sub can really hit hard and I listen to music louder or watch movies with a lot of SFX and big soundtracks all the time.

You are the nightmare I continually dread moving next door to me.