Re: Is this a good way to test pre-amp hiss of a digital recorder?

A short circuit at the input gives more consistent results
when comparing preamps. While the noise inherent in a
600 or 150 ohm resistor isn't likely to corrupt your results,
different preamps can have different internal noise with
different source resistances. A short is a short is a short
regardless of the input stage configuration.

And if you're using 600-ohm mics, then THAT is consistent.

You can only get valid results by testing under the conditions under which
the product will be used. A short circuit is not that condition.


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