Decibels (dB) is a measurement of sound.
It scales in a weird way: Increase dB by 3 (from 10 to 13, 13 to 16, etc.), and it doubles the power from the source.
Sound creates a pressure wave in the air, and that's measured as Sound Pressure Level (SPL).
When that pressure wave hits your ear, you hear the sound.
For every 6 dB added to the SPL, the perceived loudness doubles.
So if you have a sound at 100 dB and then increase it to 106 dB, the power from the source is 4x, but the sound will only be 2x as loud as before when it reaches your ear.
Sounds louder than 120 dB can cause immediate hearing loss.
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Pistol shots are around 163 dB.
[2]
Earpro has a noise reduction rating (NRR): how much it reduces dB. More is better.
If a gunshot went off right by you at 163 dB, but you were wearing NRR 43 earpro, your ears would get 120 dB of sound.
No immediate hearing loss.
However, that protection makes everything harder to hear.
Maybe a friend or instructor is trying to tell you something.
Or, someone is sneaking up on you.
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How do we protect our hearing while hearing important stuff like that?
Electronic vs. Passive Earpro
Electronic
Electronic earpro uses microphones to pick up sounds around you and play them inside your protected ears.
You set the volume, like listening to music on headphones.
What happens when a gunshot goes off? It depends on the type of speakers:
Cutoff speakers: Loud noise cuts the speakers until noise levels get safe.
Compressor speakers: Loud noise gets adjusted to safe levels, while not affecting the already safe sounds.
Electronic earpro always has volume controls, microphones, and wires:
Newer electronic earpro has microphones that pick up sounds well enough that you can tell where sounds are coming from.
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Passive
Passive earpro just muffles all sounds. It has a smooth shell. No wires or switches:
They save money:
Passive earmuffs, NRR 30: $20
Electronic earmuffs, NRR 30: $55 and up
Which is Better?
Get electronic earpro for:
Situational awareness when you shoot
Hear people talking when you shoot
Get passive earpro for:
Cheapest earpro
Most protection
Don't need to hear people speaking, or sneaking up on you
If the right choice seems clear, there's still something else:
How big do you want your earpro to be?
Earmuffs vs. Earplugs
Earplugs
Earplugs fit inside your ear. They're cheap and convenient.
You might be thinking of the cheap, disposable earplugs.
They're great as a backup, but they kill sound quality.
If someone's talking to you, they'll be hard to understand, even if they yell.
High-fidelity earplugs are made for people who want to enjoy a concert while also protecting their hearing.
They're non-disposable, and retain high sound quality.
For shooting, they'll protect you and let you understand speech.
That comes in handy at training classes, or if you want a better range experience with friends.
Earmuffs
Earmuffs are like headphones. They're bulky, and more expensive than earplugs.
But that bulk has a good side:
Passive earmuffs protect your ears more.
Electronic earmuffs have better sound quality.
Electronic earmuffs give better situational awareness.
Our Solution
Double up: Wear passive earplugs under electronic earmuffs. Why?
You can turn up the volume on electronic earmuffs and still hear everything.
You can be in a training class or long range day without losing hearing.
There are a few things to be aware of, though.
When Doubling Up, the Total NRR Isn't What You'd Expect
Some recommend taking the most protective of the two and adding 5.
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However, experiments have shown that doubling up results in 85-95% of the combined NRR, or 12-20 NRR of extra protection.
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Other experiments had NRR increases of 2-13, 2-14, 3-14, 3-17, and 7-17, depending on the earplugs/muffs.
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So if you had 30 NRR muffs with 20 NRR earplugs, the conventional wisdom is to expect 35 NRR.
What you can really expect based on experiments (and modern gear) is 42-47 NRR.
Why is this? Sounds come in different frequencies, like treble vs. bass.
NRR takes the average of protection across all those frequencies. An example:
Most gunfire is loudest at 500Hz, and remains high through 8,000 Hz.
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Human speech is 85-255 Hz.
If either muffs or plugs give awesome protection against a frequency, adding more protection helps, but not as much.
If both muffs and plugs are weak against a frequency, then their combined NRR won't be much better against that.
If one covers the other's weakness, though, you gain NRR at the high end.
This is why the experiments cited above had NRR improvements of 2-20 dB from doubling up.
Limits of Doubling Up
Even with the best muffs and plugs, you can't go above a total of 40-50 NRR. Why?
Most sounds travel through the air and into our ears.
But extremely loud sounds can travel through our bones to reach inside our ears.
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Ever felt a sound so loud you could feel it in your chest? Earpro can't help you as much there. You'd need a full body suit to protect your hearing.
Earpro in Practice
Here's a secret: Sustained noise at "safe" levels can still damage your hearing.
Each gunshot's sound wave lasts up to 5 milliseconds.
[25]200 gunshots make 1 second of noise.
Pistol Shots until Hearing Loss
Practicing alone, you may go through 200 rounds. But in group practice or training, all the people around you will be firing, too.
Outdoors, some of that sound drops off with distance, but being indoors amplifies the sound (as much as 8x).
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How do we account for that?
At this price point, the Howard Leight Impact Pro offers great protection, awesome battery life, and stereo sound at acceptable quality.
What's the catch? For some people, its bulk can get in the way when shooting a rifle or shotgun, breaking the earmuff seal and degrading sound protection.
The Walker's Razor Slim offers a slim profile for more versatile use, at the cost of some hearing protection and mono sound.
If you only shoot pistols, get the Howard Leight. Otherwise, the Walker's may be a better choice, doubled-up with earplugs like the SureFire Sonic Defenders.
The Peltor Sport Tactical 300 seems like a great choice, with good NRR and great sound quality.
Only downside? The headband inexplicably has no padding. Wear a hat with this one.
The MSA Sordin Supreme Pro X may seem a worse choice, but beware: its NRR is deceptive.
It's built in a way that minimizes noise reduction from speech and lower-frequency sounds (NRR 16), while maximizing noise reduction from gunshots (NRR 21-28).
Its average NRR of 18 seems low, but for shooters, it really isn't. And its headband is much more comfy.
If you want more comfort, get the MSA Sordin. If you want more hearing protection, get the Peltor.
True NRR is 16 for speech and lower-frequency sounds, 21 for mid-frequency, and 31-39 for high frequency.
Gunshots are mid to high frequency.
True NRR is 16 for speech and lower-frequency sounds, 23 for mid-frequency, and 25-38 for high frequency.
Gunshots are mid to high frequency.
Best Electronic Earmuffs for over $250
The OPS-Core AMP with NFMI Earplugs is the Holy Grail headset that special forces use.
Why? Normally, combining earplugs and earmuffs maxes out protection at the cost of sound quality and directional hearing.
Special forces need to sneak around and detect enemies, so that doesn't work.
The OPS-Core AMP earmuffs and NMFI earplugs use the latest technology to work together as a system, giving top sound quality, directional hearing, and max protection.
It enhances your hearing while protecting it. It's the ultimate in hearing protection.
With earplugs, the choice is simple. If you have electronic earmuffs, use the SureFire Sonic Defenders for max hearing protection.
If you want electronic earpro you can carry in your pocket, consider the Peltor TEP-100s.
Bryan Hill 
