Noise cancelling ECM’s are ported, or open, on both the front and back sides of the element. Unwanted background noise enters the front and back ports and hits the mic diaphragm at the same time thereby cancelling itself out. The user’s voice is both stronger and closer to the front of the ECM, and enters the front ports and hits the mic diaphragm before the voice sound waves can reach the back ports of the microphone element. This is the same noise cancelling technology used by the military for use in helicopters and other extreme noise environments.
Why Not Dynamic?
The simple answer is audio quality. Dynamic microphone elements do not have the sensitivity or gain that a ECM element has. More sensitivity and gain makes an ECM sound better and louder over a dynamic element. Since the SL41 has more gain and output than a dynamic microphone means you no longer need to run your radio’s mic gain control wide open to be heard. The extra gain from the SL41 allows you to turn down your radio’s mic gain and still be louder than a dynamic microphone with the radio mic gain at full.
Super Long Life Battery.
ECM’s require a small amount of voltage to work and therefore the SL41 does have a single AAA battery inside. The SL41’s circuit focuses on maximizing the battery life. Under normal operating conditions, a single AAA battery will power the SL41 for 2 years! When it does finally come time to install a new battery, this is as easy as removing 3 screws.
Built to Last
No expense was spared in making the SL41. Every part and component is top of the line, from the massive PTT switch to the custom designed mic cord with dual shields. Our case uses more than 50% the amount of impact proof ABS plastic as our competitors, which makes the SL41 feel as solid as it sounds.
Features & Specifications:
- Classic Rugged Design
- Heavy-Duty, Impact Proof Case
- Active Circuit Noise Cancelling Microphone
- 6 Conductor, Dual Shielded Custom Cable
- 16" Coiled Cable Section - Stretches to 9+ Feet
- 2 Year Battery Life from Single AAA Battery
- Industrial Grade Push-to-Talk Switch
- Dual Mount - Aluminum Button + Hanger
- Wired for 4-Pin standaard CB Radios
Specifications (Typical):
- Frequency Response: 20 ~ 16,000 Hz
- Sensitivity (0dB=1v/μbar, 1kHz): -54dB (±5dB)
- Impedance: 680
- Directivity: Bi-Directional, Noise Cancelling
- Weight: 9.5 oz (270 Gram)
- Color: Black
Wiring:
- Shield................................................................................ Ground (PTT)
- Red................................................................................... Transmit (PTT)
- White (center conductor) ................................Microphone Audio
- White (shield).....................................................Ground (Mic Audio)
- Blue...................................................................................Receive Audio
- Black ................................................................................not connected
- Yellow.............................................................................not connected