# What kind of microphones does aviation use?

Do they use the dynamic ones or cheap ribbon ones? Also why are these microphones so small?

I guess they dont use condensers. (I am yet to see an 3.5mm jack (which is used both on the C172 and the B747) that can supply 48V phantom power to the one of those)

• "Cheap ribbon ones?" The cheapest ribbon mics nowadays are \$500+. They're specialty studio microphones and they're big heavy things. They're also very delicate, so they would be no good for a headset mic. Can't get much cheaper than an electret condenser and they're practically indestructible. – TomMcW Jun 19 '19 at 0:06

## 1 Answer

Microphones used in aviation are usually electret condenser microphones that do not require any phantom power (obviously there are different types as well).

While General Aviation Aircraft and many airliners use the dual PJ connectors (PJ-055 for headphones + PJ-068 for microphone), the Airbus and ATR aircraft (and probably some others) use XLR connectors. Most helicopters use the combined U-174 connector for both headphones and microphone.

• What is the voice quality difference between the XLR ones used by Airbus and the regular ones used by the rest? – Delta Oscar Uniform Jun 18 '19 at 18:45
• Audio quality usually isn't a concern when selecting a connector type. In terms of quality the microphone and electronics are more important, but in the end an aircraft is not the opera so it doesn't matter too much. XLR has the advantage of being able to provide power if needed while the PJ connectors do not as far as I know. Audio quality on the radio communications is limited by the bandwith available for the radio channel which is very limited. – rauberdaniel Jun 18 '19 at 18:48
• When I bought my Dave Clarks in 1976 they were still offering a carbon mic and the option was the dynamic mic. The carbon mic made you sound like you were talking from inside a trash can with the mic right in your mouth, so dynamic it was. Electrets were just coming out and that option was quite expensive. You can tell the dynamic mic on a DC because of the amp circuit for it which makes the housing quite large. I can't tell any difference between sound quality between dynamic and electret. – John K Jun 18 '19 at 20:48