In article , Iain M Churches
wrote:

"Arny Krueger" wrote in message
...


Yes, but you are conventiently missing out the rest of the
specification. 600 Ohms - balanced line on XLR.

What's convenient about that?

Because Arny, my dear fellow, it doesn't mean a thing if the OP is
single ended. And if it is, the 400 Ohms is pretty high (unless of
course it's a cathode follower:-)))

I'm afraid I've lost/forgotten the context here. However in my view I would
say that in general, for domestic audio equipment, a 400 Ohm source
impedance isn't what I'd call "high". The anticipated loads are only of the
order of 1000pF//10kOhms or higher, and I'd expect a 400 Ohm source not to
have problems delivering across the audio band into such a load. I'd also
expect 400 Ohms to be low enough to avoid noise or distortion problems in
the receiver.

The situation is no doubt different in professional situations where long
balanced lines may be required, and where impedance matching is desirable.

Slainte,

Jim

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