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Don Pearce[_3_] Don Pearce[_3_] is offline
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Default Does anybody sell pre-made resistor "gizmos" for sm57/58 mics?

On Thu, 17 Sep 2020 10:25:58 -0700 (PDT), "Roy W. Rising"
wrote:

On Wednesday, September 16, 2020 at 4:03:58 PM UTC-7, geoff wrote:
Surely all passive ribbon mics have output transformers, and the optimal
loading would be dependent on that, which could be different for every
model or brand ?

Let me repeat: Microphone preamp input impedances should be 2K ohms or greater to *avoid* loading ribbon mics. "Optimal loading" would be NO loading whatsoever.


There is an equally important impedance requirement in the other
direction. To achieve the lowest possible noise level the microphone
impedance as seen by the pre must be about right. Typically this is
about 150 ohms. This is determined by the balance of voltage noise and
current noise in the preamp. Many of the top mixers are pretty poor in
this regard; something that was not very important until the new
generation of ultra-low self noise mics came along.

d

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