[Ian Thompson-Bell]

Les. wrote:
"Martin Griffith" wrote in message
...
On Sat, 3 May 2008 17:01:19 +0100, in sci.electronics.design Ian
Jackson wrote:
600 ohms is dead and buried, for the audio world.The only time it is
mentioned is in data sheets, "will drive XXdB into 600R" etc


martin

Quite so. The concept of matching a microphone's impedance to get the best
power transfer has not been practiced for a considerable time.
Modern dynamic mics expect to look at a "bridging" impedance e.g. around 10K
for a mic having a Z of 150-200 Ohms and to operate as a voltage, rather
than a power source.

No they expect to see 1K2 to 2K not 10K and that is what most pro mic
pres provide. 10K input impedance is for bridging line levels.

Cheers

Ian