Since this thread popped up again, why not jack it again?
Unfortunately I can't find the link (again), but I recently saw another study that specifically attempted to measure the protection vs cancellation question. Bottom line, cancellation was very effective at reducing actual noise at the frequencies it excels at, specifically low frequencies. That makes sense given how much engine rumble you can reduce when you turn the system on.
But higher frequencies aren't truly defeated by cancellation and can still get through to cause damage. Something of note if flying pistons, but a much bigger deal if flying turbines. These higher freqs are better mitigated by attenuation. Unfortunately the modern NC headset is pretty weak on attenuation in an effort to save weight, so their passive hearing protection isn't great, and less than the standard DC 13.4 headset that's been around for several decades (and still work great).
All that said, am I trashing my Lightspeed and going back to my David Clark? No, but for the next headset I buy (whenever that might be), it might be worth looking at the passive attenuation more closely. I think that may be a benefit of the ANR David Clark model that used to be sold (and may still be). I might have to steal my dad's since he's not using it anymore.
Unfortunately I can't find the link (again), but I recently saw another study that specifically attempted to measure the protection vs cancellation question. Bottom line, cancellation was very effective at reducing actual noise at the frequencies it excels at, specifically low frequencies. That makes sense given how much engine rumble you can reduce when you turn the system on.
But higher frequencies aren't truly defeated by cancellation and can still get through to cause damage. Something of note if flying pistons, but a much bigger deal if flying turbines. These higher freqs are better mitigated by attenuation. Unfortunately the modern NC headset is pretty weak on attenuation in an effort to save weight, so their passive hearing protection isn't great, and less than the standard DC 13.4 headset that's been around for several decades (and still work great).
All that said, am I trashing my Lightspeed and going back to my David Clark? No, but for the next headset I buy (whenever that might be), it might be worth looking at the passive attenuation more closely. I think that may be a benefit of the ANR David Clark model that used to be sold (and may still be). I might have to steal my dad's since he's not using it anymore.