View Full Version : Headset Microphone Impedance
redED
24th Feb 2012, 22:05
Just been told by our company that we are no longer allowed to use Bose headsets on our Embraers as the microphone impedance (5 Ohms) is outside the manufacturers limits 50-150 Ohms.
Please could someone with a bit more technical knowledge explain this one to me . . .
Dream Land
25th Feb 2012, 04:00
I believe that this situation creates low audio quality and needs to be boosted, although a low impedance microphone is actually better. Looking at the Telex Airman 750 specs, it lists mic impedance at 150.
hetfield
25th Feb 2012, 04:06
A lower mic impedance means lower output. There will be no damage but it may be simply not loud enough.
formulaben
25th Feb 2012, 05:19
If you want quiet, consider the Airman 850. Which Embraer aircraft is it? If it is one of the ERJs than I HIGHLY recommend the 850. It has active noise cancellation with no batteries (uses Mic bias), adjustable mic gain and high/low volume select to augment your audio panel, is within your required spec, and is not much more than the 750 model. :ok:
Telex Airman 850 Lightweight, FAA TSO approved, ANR headset, no batteries or panel power (http://www.telex.com/us/aviation/product/Airman_850/1075)