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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-06 · 7 min read · Independent comparison
• ProCase NRR 32dB — biggest strength: An NRR 32dB rating (SNR 34dB) with ANSI S3.19 certification. That's a lot of passive attenuation, and it doesn't depend on a battery, a firmware update, or a Bluetooth pairing.
• ProCase NRR 32dB — biggest trade-off: It's a pure muff. No Bluetooth, no microphones, no audio. You get silence and comfort, not sound. It's also a metal-band over-ear design, so it's bulkier than earbuds.
• ULTRX Allen Company Bionic — biggest strength: Bluetooth 5.3 streaming plus four hi-gain omni-directional microphones that shut down automatically at 82dB within 0.02 seconds. You get situational awareness and audio in one unit.
• ULTRX Allen Company Bionic — biggest trade-off: The passive rating is NRR 22dB, a full 10dB below the ProCase. If your environment is genuinely punishing, that gap matters.
• Who ProCase is for: Shooters, mowers, woodworkers, factory workers, and anyone with noise sensitivity who wants maximum quiet with zero complexity.
• Who ULTRX is for: People who want ear protection that doubles as a Bluetooth headset—range time, yardwork, construction, and yes, calls and streaming.
The ProCase NRR 32dB is a single-purpose tool, and that's its appeal. The headline number is the NRR 32dB rating, backed by ANSI S3.19 certification, with an SNR of 34dB. In plain terms, that's a serious chunk of passive attenuation—the kind you want when you're standing near a running mower, a table saw, a firing line, or heavy equipment. There's no circuitry to fail and nothing to charge. You put them on and the world gets quieter.
Beyond the shop and the range, ProCase leans hard into sensory support. The listing calls out autism sensory needs, noise sensitivity, crowds, airports, fireworks, and busy public spaces. That's a real use case, and a 32dB passive muff is arguably better suited to it than anything with a speaker inside. If your goal is to reduce overwhelming sound—not to listen to anything—the ProCase does exactly one thing and does it without asking anything of you.
The design is foldable, so it collapses into backpacks, luggage, and tool bags. It weighs 10.6 ounces, which is noticeable but normal for this class of muff. The materials are listed as sponge and plastic, with a metal band, in black, sized large and marked for adults. There's also a kid angle here—the listing frames it for both adults and kids, which is unusual for a 32dB unit and worth noting if you're buying for a household rather than one person.
Who should skip it? Anyone who wants to take a call, stream music, or hear a coworker shout a warning while wearing them. There is no Bluetooth and no microphone. If you need audio, this isn't the product. Check the current price on Amazon before you commit, since that's the one thing I can't tell you here.
The ULTRX Allen Company Bionic is the opposite philosophy: protect your hearing, but don't cut yourself off from the world. It carries an NRR of 22dB—respectable, but 10dB less attenuation than the ProCase. What you trade that protection for is capability. Bluetooth 5.3 lets you stream from your phone or laptop, and the listing describes digital studio harmonics tuned for clear, natural sound.
The more interesting feature for anyone working outdoors or on a range is the microphone array. Four hi-gain omni-directional microphones pick up surrounding sound so you stay aware of what's happening around you—someone approaching, a machine engaging, a range officer calling a cease-fire. Those mics automatically shut down at 82dB within 0.02 seconds. So quiet conversation comes through amplified, and a gunshot or a saw blade gets clamped instantly. That's the "noise-activated protection" the spec sheet describes, and it's the reason this style of muff exists at all.
Comfort is clearly a design priority. Soft padded headband, gel ear cups, and a folding frame for transport. The housing is ABS plastic, the color is midnight gray, and it's a one-size adult fit. It ships with a 2-year manufacturer warranty, which is a meaningful detail if you're hard on gear. Weight is listed at 0.4 kg, so it's in the same ballpark as the ProCase despite packing electronics.
The honest limitation: it's not a quiet-room device. At 22dB, it won't flatten a genuinely brutal noise environment the way a 32dB passive muff will. And it's an over-ear muff, not a true wireless earbud, so if you were searching for wireless earbuds for Zoom calls, understand that this is a headband device with cups—not something you'll forget you're wearing.
Who should skip it? Anyone whose primary need is maximum attenuation for hours in extreme noise, and anyone who doesn't want to manage a battery. If silence is the goal, the ProCase wins.
• Best passive noise reduction → ProCase NRR 32dB. NRR 32dB versus NRR 22dB is not a rounding error. That's the single biggest spec difference between these two.
• Best for hearing your surroundings → ULTRX Allen Company Bionic. Four hi-gain omni-directional mics with a 0.02-second cutoff at 82dB are built specifically for awareness.
• Best for streaming and calls → ULTRX Allen Company Bionic. Bluetooth 5.3 is the only audio path on either product.
• Best for sensory support and noise sensitivity → ProCase NRR 32dB. The listing explicitly targets autism sensory needs, crowds, airports, and fireworks. Zero setup, zero charging.
• Best for shooting ranges → Depends on your priority. ProCase for maximum attenuation; ULTRX if you want amplified range commands and music between strings.
• Best for mowing, woodworking, and construction → ProCase NRR 32dB if noise is the enemy; ULTRX if you want a podcast running while you work.
• Best for travel and packing → Tie. Both fold. ProCase at 10.6 ounces, ULTRX at 0.4 kg. Neither is a burden in a bag.
• Best for low-maintenance ownership → ProCase NRR 32dB. No battery, no pairing, no firmware. Just sponge, plastic, and a metal band.
If I'm buying for myself and my main goal is quiet—real quiet—I'm taking the ProCase NRR 32dB. A 32dB passive rating with ANSI S3.19 certification is the harder number to fake, and I like that there's nothing to charge before a range day or a mowing session. That said, I'd genuinely recommend the ULTRX Allen Company Bionic to a different person entirely: someone who wants one pair of muffs for yardwork, range trips, and streaming, and who values hearing their surroundings over maximum attenuation. If you're specifically chasing noise canceling open ear headphones for zoom calls, neither of these is that product—but the ULTRX gets you closer to a connected experience, while the ProCase gives you the deepest silence for the focus hours around those calls. Check the current price on Amazon for both, then match the spec to your actual day.
how do passive noise cancelling headphones work
They don't use electronics at all. Passive protection relies on physical barriers—dense materials, sealed ear cups, and a tight fit—to block sound from reaching your ear. The ProCase NRR 32dB and the ULTRX Bionic at NRR 22dB are both passive designs; the ProCase simply blocks more because it has a higher rating and no audio hardware competing for space inside the cup.
what is passive noise cancelling headphones
The term describes hearing protection that reduces noise through materials and fit rather than active circuitry. The ProCase uses sponge and plastic construction with a metal band to achieve NRR 32dB, while the ULTRX combines an NRR 22dB passive rating with Bluetooth 5.3 and four microphones for awareness. Active noise cancellation, by contrast, uses powered electronics to generate opposing sound—neither of these products works that way.
what does passive noise cancelling headphones mean
It means the noise reduction comes from the physical design: the cups, the padding, and how well they seal around your ears. In practice, that means no battery and no charging, but also no adjustable or adaptive noise control. The ProCase's 32dB rating and the ULTRX's 22dB rating are both fixed passive figures.
what are passive noise cancelling headphones
They're earmuffs or ear cups built to attenuate sound through mass and sealing. The ProCase NRR 32dB is the purer example—foldable, 10.6 ounces, ANSI S3.19 certified, no electronics. The ULTRX Allen Company Bionic is a hybrid: passive cups at NRR 22dB plus Bluetooth and a microphone array that shuts down at 82dB in 0.02 seconds. Pick based on whether you want silence or connectivity.
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