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gabasa

Circuit Question
« on: January 04, 2017, 08:00:54 PM »
Hi All,

I was comparing some AKG schematics earlier and one question came to mind while looking at this one:
http://www.gyraf.dk/schematics/AKG_C414B-TL.GIF

If you can find the R119 and R120 1k resistors (a little to the left of the XLR connector in the lower image), would you say the the audio signal passes through them?  Of two engineers that I know, one said yes while the other said no, so now I'm a little confused!

Thanks.   :)


ruffrecords

Re: Circuit Question
« Reply #1 on: January 05, 2017, 03:29:37 AM »
Perhaps they are both right. The two 1K resistors are in series between the hot and cold outputs some some signal current will pass through them but the audio does not go through them on its way to the  XLR. These two resistors are there to take the phantom dc voltage from the hot and cold connections and feed it to the power supply circuit.

Cheers

Ian