Talk-Through
Level Dependent Functionaility, commonly referred to as “talk-thru,” is a means of allowing safe audio sounds to bypass the individual hearing protection while still protecting against harmful noises. This can be accomplished with a proprietary digital audio circuit integrated into the headset. A microphone will receive sounds outside its headset and transmit those to a speaker inside the headset. This Level Dependent Digital Audio Circuit easily senses noise levels above the desired threshold and compresses each to a safe decibel level or amplifies weak sounds to an audible level.
Compression vs. Clipping
3M has incorporated compression technology to remove the “clipping” effect heard in common talk-thru systems. “Clipping” can result in missing the first syllable of important commands. This technology resolves that issue and dramatically improves speech intelligibility.
Fail Safe
ComTac External Communication (i.e. radio or intercom) and “talk thru” are completely independent of one another. In the unlikely event of electronic failure or battery depletion, external communications will continue to function.
Environmental
-MIL STD 810F, Department of Defense Test Method Standard for Environmental Engineering Considerations and Laboratory Tests
-Submersion: 3 feet, 30 minutes, salt-water-survivable
EMI
-MIL STD 461E, Department of Defense Interface Standard, Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment
-CS1 14, RE101, RE-102-4, RS101 and RS103 Requirements
Noise Reduction Ratings(NRR)
(per ANSI S3.19-1974; NAVLAP Certified - Tested internally at 3M’s NAVLAP-accredited facility)
-COMTAC III ACH (headband version, standard foam cushion): NRR 23 dB
-COMTAC IV: Classic Foam Eartip - NRR 30 dB; UltraFit Reusable Eartip - NRR 18 dB
