Microphone cable resistance

[Phrazemaster]

Hi, I just put together a mic cable for a U47 clone. I used Gotham GAC-7 cable.

I noted after putting it together that the thicker wires had .4R through the cable (about 20' length), but the audio signal-bearing thinner wires measured 1R. The ground and shield were only at .2R (I combined them on the advice of a pro).

Anyway, should I be concerned at the 1R across the audio cables? The wires look to be about 24 or 26AWG. It just seemed like a big loss, but each of the smaller wires incurred the same loss so I'm pretty sure it isn't bad soldering or connections.

Thanks,

Mike

PS hope this is the right forum for this; it is a valve mic!

 

[HellfireStudios]

The Gotham cable is excellent. The thicker wires are there to carry more current. Maybe someone here could shed some light on which leads (plate, heater, ground) would require the thicker wires, as I have found people hook them up differently depending who you ask.

-James-

 

[Phrazemaster]

Thanks hellfire, I used the thicker wires for ground and heater current, on the advice of a mic tech. Of the 7 wires, I used 5 and cut 2 short. I thought about doubling the audio connections with the extra wires, but I was worried about adding phase problems due to different wire lengths, and since it wasn't suggested I just didn't do it.

Beast to wire it up; tight spaces for soldering!

here's a pic of the finished cable attached.

Thanks for your thoughts and any other thoughts.

 

[zebra50]

The thicker wires are for the heater - there and back - which requires more current.
z50.

 

[Phrazemaster]

That's what I did...the ground is heater return too...thx for sharing.