On Wed, 26 Apr 2006 10:14:47 +0100, "Dave Plowman (News)"
wrote:

In article ,
Arfa Daily wrote:
Mics with XLR connection systems are often 600 ohm matched, and
balanced, although may be 10k if they don't contain a 600 ohm line
matching transformer.

In broadcasting the most common combination with balanced mics is an
approx 150-300 ohm output going into an about 1.2k input on the mixer.
Older STC ribbons were sometimes 30 ohms. Accurate 600 ohm matching only
really was used into very long lines. Like telephones. But most long lines
these days will be digital.

Shouldn't that be 12k in? A pair of 6.2k ohms in series feeding the
phantom power would give you that. Even with phantom switched off, the
resistors are still there, so the input impedance doesn't get any
higher for dynamics.

d

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