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Mic Output levels...

In other circuits (e.g. FM Modulators) it's usually not an issue.? That said a Mic with output of -44 db will drive an older ICOM analog (traditional heterodyne type SSB transceiver), to proper ALC levels with the Mic gain set near 50%.

Then there is the difference in intended use of the?Mic and there are three types of Mics.

1) There are consumer Electret-Condenser Mics that have these output levels with the?mic at some distance to the?mouth.??

2) A Close-Talk, Noise-Canceling, "communications grade" (e.g. Aviation Mics) that level is reached with the?Mic centered in front of your mouth with it set at 1/8" from your lips.? Then the acoustic noise cancelling?works, and the?output levels are maintained.

3) Now typical Studio Electret-Condenser?Mics?are yet different again with 48V "Phantom Power" (rather than 5V through a 4.7K ohm resistor for Mic BIAS).? This likely came from the AT&T networks that provided communications from the studio to the transmitter, but I'll confirm that with Dave, WJ6W he knows this stuff.

Collins Radio set the?standards for Aviation radio interfaces, and those interfaces are still used today (.206" Mic plug to differentiate it from the .250" Headphone Plug) with a high impedance Dynamic Mic.? Today the modern general aviation radios all use Electret-Condenser Mics (600 to 2K Ohm Mics). The exception is a military helicopter headset where the Mic is typically a 5 Ohm Close-Talk, Noise-Canceling, Dynamic Mic due to the extreme noise levels they must contend with.

Dave WI6R