Robatoy wrote:
On Apr 8, 4:35 pm, Chris Friesen wrote:
jeffgee wrote:
I have been using some earbuds for music and then some big earmuff
style hearing protectors over them. I have been shopping for
headphones and was wondering what the group thinks of using noise
reducing headphones for hearing protection. I have a feeling they only
stop normal noise and would not provide the protection I am looking
for
Depends what you're willing to spend. $150 gets you some Etymotic hf5
earbuds, which have 35-42dB of passive isolation.

35 to 42 dB of isolation from an earbud? MAYbe at one specific
frequency. Even then I have my doubts. Let me rephrase that: Naaaaa.
The entry to the ear canal is only a part of the sound detection our
ears give us. A lot of sound will get by those plugs from the outside
of the ear shell, through the mouth and transconductance through the
skull.

I have custom-molded earplugs for hearing protection. They're supposed
to give around 30dB attenuation from 125Hz until about 600Hz, and then
ramp up to 45dB at 4kHz. No idea what they give below 125Hz.

I suspect the Etymotic ratings are biased towards higher frequencies.

Those big humongous muffs that the boys on the flight deck wear, are
nowhere near 42 dB. More like -27dB.
-27dB muffs are good muffs. -30dB would be a whole magnitude better.

My big humongous Peltor muffs are rated at 35dB attenuation. According
to their frequency response curve they range from 15dB at 125Hz to 30dB
at 500Hz, to 43dB at 4kHz.

Chris