[dioxholster]

I know how sound level is measured but when can one say that music or that movie at home or in theater is too loud for peoples ears?

 

[alv4426]

If you have to ask its too loud.

 

[dioxholster]

Quote:

If you have to ask its too loud.

yes but sometimes the sound effects are too loud but dialogue isnt loud enough...

 

[jaddie]

Quote:

I know how sound level is measured but when can one say that music or that movie at home or in theater is too loud for peoples ears?

You probably can't without a sound measuring device.  Sound level is measured with meter calibrated to read "Sound Pressure Level", SPL for short.  All noise exposure figures published by OSHA are stated in SPL for a certain amount of exposure time.  Without experience in knowing what a particular SPL sounds like, you can't even guess how loud something is.  SPL meters are not expensive, though.  Even Radio Shack has (or had) one that wasn't too bad, at least in the general ball park. 
 
Movie theaters are supposed to be calibrated so that the sound levels can be high enough for impact and effects, but not harmful.  If you have trouble hearing dialog, there is a chance the center channel level is too low, as thats where all the dialog is.  Home systems without a center speaker often have trouble with low dialog because there's no speaker for it.

 

[deltawave]

Hey there,

I run FOH audio for a living. I'm a concert audio engineer.
There are many things to take into account when looking at your Db (decibel) measurements, weather that be with a simple meter, or an RTA spectrum analyser (shows audio intensity per frequency).
The biggest thing to take into account is the ratio of frequencies with one another, if you were to have vocals at 100Db by themselves, that could potentially be more damaging to your ears let alone be perceived as much louder than a full band at 100Db

One option that most OSHA standard meters have in common is a weighting system. There is normally an A weighting, and a C weighting (others as well but these are the most common). The differences between the two is the low end roll off. A weighting rolls off more of the sub frequencies, as C weighting is more of a flat response. (However C weighting still partially rolls off low end). I almost always mix a concert/event in the A weighting on my meter, this works well for me because it is the same weighting that OSHA uses.

When talking about what is "too loud" it is usually a very realitive statement, as a rock concert may be 110Dba-120Dba, yet that only lasts a couple of hours. I almost always find that prolonged exposure is much worse for your ears than short increased ammounts of sound.

I'll attach an OSHA chart from their website, it is generally what I use.



TABLE G-16 - PERMISSIBLE NOISE EXPOSURES (1)
______________________________________________________________
|
Duration per day, hours | Sound level dBA slow response
____________________________|_________________________________
|
8...........................| 90
6...........................| 92
4...........................| 95
3...........................| 97
2...........................| 100
1 1/2 ......................| 102
1...........................| 105
1/2 ........................| 110
1/4 or less................| 115
____________________________|________________________________
Footnote(1) When the daily noise exposure is composed of two or
more periods of noise exposure of different levels, their combined
effect should be considered, rather than the individual effect of
each. If the sum of the following fractions: C(1)/T(1) + C(2)/T(2)
C(n)/T(n) exceeds unity, then, the mixed exposure should be
considered to exceed the limit value. Cn indicates the total time of
exposure at a specified noise level, and Tn indicates the total time
of exposure permitted at that level. Exposure to impulsive or impact
noise should not exceed 140 dB peak sound pressure level.



Hope this helps!

 

[jaddie]

Quote:

Hey there,

I run FOH audio for a living. I'm a concert audio engineer.
There are many things to take into account when looking at your Db (decibel) measurements, weather that be with a simple meter, or an RTA spectrum analyser (shows audio intensity per frequency).
The biggest thing to take into account is the ratio of frequencies with one another, if you were to have vocals at 100Db by themselves, that could potentially be more damaging to your ears let alone be perceived as much louder than a full band at 100Db

One option that most OSHA standard meters have in common is a weighting system. There is normally an A weighting, and a C weighting (others as well but these are the most common). The differences between the two is the low end roll off. A weighting rolls off more of the sub frequencies, as C weighting is more of a flat response. (However C weighting still partially rolls off low end). I almost always mix a concert/event in the A weighting on my meter, this works well for me because it is the same weighting that OSHA uses.

When talking about what is "too loud" it is usually a very realitive statement, as a rock concert may be 110Dba-120Dba, yet that only lasts a couple of hours. I almost always find that prolonged exposure is much worse for your ears than short increased ammounts of sound.

I'll attach an OSHA chart from their website, it is generally what I use.



TABLE G-16 - PERMISSIBLE NOISE EXPOSURES (1)
______________________________________________________________
|
Duration per day, hours | Sound level dBA slow response
____________________________|_________________________________
|
8...........................| 90
6...........................| 92
4...........................| 95
3...........................| 97
2...........................| 100
1 1/2 ......................| 102
1...........................| 105
1/2 ........................| 110
1/4 or less................| 115
____________________________|________________________________
Footnote(1) When the daily noise exposure is composed of two or
more periods of noise exposure of different levels, their combined
effect should be considered, rather than the individual effect of
each. If the sum of the following fractions: C(1)/T(1) + C(2)/T(2)
C(n)/T(n) exceeds unity, then, the mixed exposure should be
considered to exceed the limit value. Cn indicates the total time of
exposure at a specified noise level, and Tn indicates the total time
of exposure permitted at that level. Exposure to impulsive or impact
noise should not exceed 140 dB peak sound pressure level.



Hope this helps!

The weighting filters found on common SPL meters are A and C, and possibly flat, or no weighting.  The A weighting curve applies only to low level measurements, typically background noise below 40dB SPL, and is invalid for measuring music or speech at concert levels.  The curve itself is based on (outdated, inaccurate) equal loudness curves taken at 40 phons.
 
C weighting is the better choice at concert levels, though most meters also have a response time selection which should also be considered.
 
The exposure to 2 hours at 120dB SPL at a rock concert is well above the threshold for permanent hearing loss, as the chart posted shows.  
 
This is a bit more detailed, and more conservative:
http://expecttohearbetter.com/hearing-damage-sound-chart.html

 

[kraywang]

lol i guess when yo ear cant take no mo..

 

[deltawave]

The weighting filters found on common SPL meters are A and C, and possibly flat, or no weighting.  The A weighting curve applies only to low level measurements, typically background noise below 40dB SPL, and is invalid for measuring music or speech at concert levels.  The curve itself is based on (outdated, inaccurate) equal loudness curves taken at 40 phons.

C weighting is the better choice at concert levels, though most meters also have a response time selection which should also be considered.

The exposure to 2 hours at 120dB SPL at a rock concert is well above the threshold for permanent hearing loss, as the chart posted shows.  

This is a bit more detailed, and more conservative:
http://expecttohearbetter.com/hearing-damage-sound-chart.html

A weighting is a standard in pro audio. We use it for concert sound all the time.

Not to be argumentative but saying C weighting is valid for concert audio is incorrect.

 

[deltawave]

http://hyperphysics.phy-astr.gsu.edu/hbase/sound/acont.html

 

[Greenleaf7]

How accurate is the the decibel meter on an iPhone? I just measured my listening levels using an app called decibel 10th.

 

[jaddie]

Quote:

A weighting is a standard in pro audio. We use it for concert sound all the time.

Not to be argumentative but saying C weighting is valid for concert audio is incorrect.

Yes, I understand, and I've used the A curve in error too. However, using the A weighting curve at concert levels is one of the more common misconceptions in pro audio.  The curve is based on hearing response at 40 phons.  Hearing response at 100dB SPL is quite different.  It's a very common mistake, and a hard one to fix because if you've been using it for years, then all your references are with the A curve.  Switching now to the C curve will throw everything off for a while, but you'll end up with better accuracy.
 
The other thing people don't seem to get is the response time choices.  Slow response with a signal like speech will produce really poor accuracy.  It's another topic, but also another common miss-use of the meter.

 

[jaddie]

Quote:

How accurate is the the decibel meter on an iPhone? I just measured my listening levels using an app called decibel 10th.

Not very.  It has to be calibrated against a known reference.  Most SPL apps have a way adjust the calibration, but you still need a known reference, usually a calibrated meter in pink noise.  The other problem with the iPhone is the preamp overloads easily, so your maximum SPL is pretty much useless over 93dB or so. The fix is an external preamp and mic.

 

[deltawave]

Yes, I understand, and I've used the A curve in error too. However, using the A weighting curve at concert levels is one of the more common misconceptions in pro audio.  The curve is based on hearing response at 40 phons.  Hearing response at 100dB SPL is quite different.  It's a very common mistake, and a hard one to fix because if you've been using it for years, then all your references are with the A curve.  Switching now to the C curve will throw everything off for a while, but you'll end up with better accuracy.

The other thing people don't seem to get is the response time choices.  Slow response with a signal like speech will produce really poor accuracy.  It's another topic, but also another common miss-use of the meter.

If you'd like to run with C weighting, be my guest brother! However every major artist I have ever worked with, and every production company I've worked for has used A weighting. I'm not saying its perfect, but when I was in school every one of my audio instructors has taught me to use A.

Why is it that you use C when mixing? Doesn't it cause your sub frequencies to rate too high? What spectrum analyzer settings do you use when mixing?

Also, is there an audio section of the forums centered around flat response studio/live monitors?

 

[jaddie]

Quote:

If you'd like to run with C weighting, be my guest brother! However every major artist I have ever worked with, and every production company I've worked for has used A weighting. I'm not saying its perfect, but when I was in school every one of my audio instructors has taught me to use A.

So, this is one of those situations where the adopted standard is actually not correct, but as a standard you have to use it, right or wrong.  As I've already explained, A-weighting would be correct for sounds at 40 phons (40dB SPL @1KHz) and down, but progressively more incorrect above that.  Pretty much way off by 100dB or so.  For accurate SPL readings you need C weighting.  
 
But, frankly, it doesn't matter what I say, because like you so accurately put it, the standard is A-weighting.  A big part of the reason we use it in concerts is that A-weighting has been officially adopted for measuring noise in relation to hearing damage, which of course is a function of exposure time, level and frequency.  
 
I already know I'm shot down on this, because of the "standard", though.

 
 
Quote:

Why is it that you use C when mixing?

I use C when measuring concert level and high PA level SPL, per the original C specs, along with fast response or peak-hold, because the A curve is correct at 40 phons (40dB SPL @ 1KHz), but not at 100dB SPL.  I also use A when I have to take measurements that have to agree with others using A.  
 
Quote:

Doesn't it cause your sub frequencies to rate too high? What spectrum analyzer settings do you use when mixing?

Also, is there an audio section of the forums centered around flat response studio/live monitors?

Please tell me you're not using an A-weighting filter in front of an RTA!  Ok, if you have to agree with someone else, or historical data taken that way, fine.  But if you're trying to get your mix to look flat on the RTA, and are at 100dB +, and have an A-weighting filter in front of the RTA, subs will be too hot. 
 
I don't use a spectrum analyzer much during mixing, mostly during setup and cal, or for finding a problem.  For that, it's C or flat, at least 1/12 octave, slow response, and with a temporal/spacial average applied over 30 seconds. 
 
No studio/flat monitor section of this particular forum that I'm aware of.  Gearslutz for sure has plenty of studio and live sound forums, possibly AVS.  

 

[coryeeeee]

It's too loud when start hearing ringing in your ears.