[romnation]

Just curious, as I work in a fairly loud environment, and am trying to avoid hearing damage caused by turning the volume up too far on my in ear monitors.
 
The ambient noise level where I work is roughly 80dbA constant I'm not sure how many decibels are reduced just by having the IEMs in. Any way to find this out? Let's just assume they reduce it by 20dbA, which would mean now my ears are only getting 60dbA of ambient noise. Now lets say my IEMs were playing at a level that I knew for a fact was 85dbA in a silent room. If I played this at the same level in the room at work with ambient noise, would my ears still be receiving just 85dbA or would they be receiving more due the the ambient noise, even though the noise is at a lower volume? If so, how many more decibels would they be receiving? 

 

[castleofargh]

it wouldn't matter much as it's a log system. the lower value will usually be almost meaningless.
what will change is that with the ambient noise, you will usually want to crank up the volume level to get the music well above this ambient noise. but in your example, if you touch nothing, the sound pressure will be almost the same.
http://www.sengpielaudio.com/calculator-spl.htm (this site has most of the calculators you will ever need in audio).

 

[romnation]

  it wouldn't matter much as it's a log system. the lower value will usually be almost meaningless.
what will change is that with the ambient noise, you will usually want to crank up the volume level to get the music well above this ambient noise. but in your example, if you touch nothing, the sound pressure will be almost the same.
http://www.sengpielaudio.com/calculator-spl.htm (this site has most of the calculators you will ever need in audio).

 
Thanks a ton! While we're on the topic of isolation, as far as custom IEMs go, does anyone know just howmany more decibels customs reduce the ambient noise versus univerisal IEMs with a proper seal?

 

[castleofargh]

usually for acrylic customs they rate them at -24 or -26db for "empty"(hollow?) shells. so often depending on the UIEM and your choice of tips, you might be able to get better than this.
my UIEM of choice for isolation is anything from etymotic, they say they can do from -35 to -42db, and I'm willing to believe it. of course when it comes to comfort and sound you might very well prefer customs ^_^. I know I do.
 
I suspect full acrylic to be on par or even better than those numbers, and from several testimonies, it seems that silicone shells are even better in that respect. but I do not know the expected values.
 
from my own experience here is my feeling on isolation:
er4(UIEM) > 334(UIEM almost full acrylic shell)+comply > jh13(CIEM hollow acrylic shell) > pretty much all other cheap UIEM I've ever tried.
 
and usually I still keep a certain volume level even with the best isolation in calm environment to avoid being disturbed by my own body noises (breathing, stomach gargles, moves...)

 

[OddE]

 
The ambient noise level where I work is roughly 80dbA constant

 
-If the ambient noise level is on the order of 80dB(A), I would strongly suggest you use proper ear muffs - a good set should give you on the order of -30dB; add the extra isolation provided by the IEMs, and your ears should be home free.

 

[davidsh]

Which iems do you use? Tyll at innerfidelity measures noise reduction for headphones for example