"Did you know noise is just like nuclear radiation? We can only endure a certain amount each day.
"Protecting yourself from harmful noise levels means you must remove the damaging dose. And just like radiation there is a limit to where exposure becomes dangerous. This limit has been established at 85 dB, A-weighed equivalent noise level, for a typical 8 hour working day. Dangerous noise levels are also a combination of noise levels over 85 dB(A), and the amount of time one is exposed to the noise.
"Generally speaking, if at some point during each 24 hour period you are exposed to a noise level over 85 dB(A), or an impulse sound of over 140 dB(C), there is a risk that you will receive a damaging dose of noise.
"A 15 minute exposure to 100 dB(A), or an impulse sound exceeding 140 dB(C), is just as harmful as 8 hours exposure to 85 dB(A) equivalent sound level.
"* It is the hair cells deep inside the ear that become damaged and do not heal. The injury becomes permanent.
"* A comfortable and accepted hearing protector, suited to the noise level of the specific work place provides the best motivation for 100% wear time, and consequently the best protection against permanent injury."

Sound Trap is a newer member of the Peltor line-up. It has slimmer cups and is a folding model. Its advantage is compact, lightweight ( 8.8 oz ), therefore most suitable when bulk and weight must be reduced to a minimum. It has a NRR of 19 dB and can attenuate hazardous noise within 5 milliseconds. For hunting and most other outdoor applications this rating is quite sufficient. It can be connected to an existing radio for communication purposes with the addition of a connecting cable, or to a CD player and other similar devices. It has one on-off/volume control knob on each side, so the user can adjust the volume level individually when neccessary. It has two microphones and two speakers, thus providing true stereo sound. It uses 4 AAA batteries, two on each side.

Tac 7 has bigger cups with more insulation material, thus providing more noise attenuation with a NRR of 24 dB. The higher NRR rating is also the result of a fixed headband design - headbands always offer better hearing protection than folding models with the same cup configurations. With this NRR rating, the Tac 7 can handle indoor / close quarter situations with ease.

When there is hazardous noise the circuit cuts down within about 2 milliseconds to protect the user. There is only one on-off/volume control knob for ease of operation. However, there are adjustment screws on the circuit boards inside the cups which allow the user to individually adjust the sound balance of the two speakers. This feature is useful for those who has hearing imbalance. Once these two screws are set, every time the headset is turned on the volume will go up and down at the correct proportion as determined before. The true stereo sound reception allows accurate determination of orientation of sound sources. The maximum sound level allowed into the ears is 82dB, same as the Sound Trap. It uses one 9 volt battery.

Both the Tac 7 and the Sound Trap can be used for communication purposes. Their communication versions are equipped with a boom microphone attached right on the headset. With the boom mic in place plus an optional adaptor, you can connect to your radio for either push-to-talk or voice-activated ( VOX ) two way communication. Adaptors are available for most major radios such as Motorola, GE, Ericsson, Kenwood....etc.

SOUND LEVELS IN ENVIRONMENT	EFFECTS
120 - 110 dB	uncomfortably loud
100 - 80 dB	very loud
70 - 60 dB	moderately loud
50 - 40 dB	quiet
10 dB	just audible
0 dB	threshold of hearing

dB	SOURCE
130	military jet take-off at 50 ft.
121	oxygen torch
118	turbo fan aircraft take-off at 200 ft.
114 - 108	rock band
110	riveting machine
106	Boeing 707/DC-8 at 6080 ft before landing
103	jet flying overhead at 1000 ft.
100	Bell J-2A helicopter at 100 ft.
97	newspaper press
96	power lawnmower
90	motorcycle
88	propeller plane flying overhead at 1000 ft.
84	diesel truck driving by at 40 mph at 50 ft.
80	kitchen garbage disposal
77	passenger car driving by at 65 mph at 25 ft.
70	vacuum cleaner
60	dishwasher ( rinse cycle ) at 10 ft.
60	air-conditioning unit at 100 ft.

"Federal Agency Review of Selected Airport Noise Analysis Issues"
<<Outdoor Noise and the Metropolitan Environment>>
Department of City Planning, City of Los Angeles, 1970.

The HT series ( listen-only ) can be connected to the radio directly for incoming signals. The MT series ( two-way ) headsets must be used in conjunction with a radio-specific adapter cable and then connected to the radio for reception and transmission. So it is a two-part ( HT ) or three-part ( MT ) system, as the case may be.

Purchasing of the HT headsets is easier, you just have to know the plug size, and whether you want mono or stereo. But purchasing of the MT headsets requires that you know exactly what the make and model of your existing radio is so that a specific adapter cable can be used to ensure proper functioning.

But the Sound Trap is more advanced in that it has an audio jack for connection to CD players, cassette players...etc ( see the next question ). It can also be purchased in a communication version where an optional boom microphone is installed with wiring to turn it into a communication headset like the MT series headsets. The Tactical 6 cannot do that.

Similar to the Sound Trap, it provides hearing protection ( 25db, much better than Sound Trap's 19db ). It also amplifies ambient sound with true stereo reception, so the user has a sense of direction where the sound comes from.

The ComTac, however, has improved electronics for longer battery life, uses 2 AA batteries instead of 4 AAA batteries, auto shut-off when left unused, low power notification, external battery compartment for easy change of batteries while wearing the headset, protected switches for better waterproof operation, low profile for fitting under a ballistic helmet...etc.

The ComTac can be purchased as a headset only. This version offers hearing protection and ambient sound amplification just like the Sound Trap.

The ComTac can also be used as a two-way communication headset, when the users can actually talk back and forth. In order to do this, there are three other components to be used with the ComTac. Please refer to http://www.precision-sports.com/qpeltor.htm#talk

One, you must have a two-way radio, such as Motorola Sabre ( or any other make and model of two-way radios ).

Two, you must purchase an adapter cable to connect the ComTac to the radio. There is an in-line push-to-talk switch on this adapter cable, so the user will not have to reach for the radio itself. This cable is radio specific, so you must specify, when ordering, what make and model radio the user will be using the ComTac with. For example, a cable for Motorola Sabre radio will not fit into a Motorola HT1000 radio, and vice versa.

Three, you must purchase the communication kit, which includes a boom microphone and split cables for hooking up the headset and the PTT adapter cable. This kit goes between the headset and the adapter cable, and can easily be installed or removed by the user without any special tools.

Once you have all four components ( the ComTac, the communication kit, the adapter cable, and the radio ), you can plug them in together and start wireless communication.

You can at any time switch off the two-way radio and the ComTac returns to its regular function as a hearing protector and an ambient sound amplifier, just like the Sound Trap. You can either swing the boom mic away from the user's face, or even remove it from the headset when it is no longer needed.

The difference between MT and HT series headsets is mainly the lack of a built-in boom microphone on the HT headsets. With this boom mic you can clip your radio on your belt, hook it up with the proper PTT cable, then up to the headset. To operate, just push the PTT button on the cable as needed, and the microphone is in place all the time. When you are not in need of communication the boom mic can easily be swung out to the side.