I was going to add - solder a jumper between pin 1 and the shield on the XLR to ensure the preamp casing and the cable shield are continuous.
I have has to do this several times where a mic will sound great when plugged into my recorder running on batteries, but buzzes like hell when you plug the power supply in.
Jack
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On 10 Jul 2024, at 13:58, Richards via groups.io <jrichards@...> wrote:
?. . . I still hear the hum although it seems to be lower) . . .
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Notwithstanding my rookie status, considering the fact the hum comes and goes jockeying the connectors ... I sorta, kinda, almost, maybe, possibly suspect what is termed the "Pin 1" problem, which you can read about here: Jim Brown K9YC is an AES guy with loads of funky ideas, some of which may be correct:
Also maybe see info and links to articles here:
I have found this sort of issue pop up in all sorts of situations, especially wiring microphones to amateur radio transceivers, sometimes requiring the cable shield to be linked to the connector case and, also therefore, equipmenent chassis, and sometimes not, it is a mixed bag - working in some cases, other times making it worse - but I figure it may be related ... or not ... remember I AM still a rookie!
Just thinking aloud out of turn ... James K8JHR
