[shuteye]

Because of a recent incident involving the left channel of my amplifier, I am testing my components for DC offset.  I was using my Perfect Wave DAC as a preamp at the time.  My question is how to properly test its outputs for DC offset with my digital multimeter (set on mV DC).  If I plug the DAC in on my workbench with no source connected, will I get an accurate reading?  Does the volume level make any difference?  Regarding XLR, do I test leads 2 and 1, then 3 and 1, with 1 as ground? 
Thanks,
Jon 

[Speedskater]

I can only help with the XLR part:
Pin #1 should be connected directly to the chassis. It's not a signal wire.
Pins 2 & 3 are the signal wires. Measure audio between these two. (including audio DC offset)
First measure AC signal (playing something) then maybe a silence level test tone.

[jtwrace]

And just in case:

[jdbrian]

Hi

  Yes, check between pin 1(ground) and pin 2 then between pin1 and 3. Unless your DAC is DC coupled you shouldn't have any DC on the outputs. Same goes for the preamp function - If the preamp is not DC coupled (most aren't) then DC should be 0. You shouldn't need any inputs plugged in to get a reading. Turn down the volume if the output is picking up noise with no input.




 

[Speedskater]

Pin 1 is connected to the chassis. Pin 1 is NOT part of the audio circuit. The reading from pin 1 to #2 or #3 is immaterial.

[shuteye]

Thanks guys for the help.  Regarding which XLR pins to test, I tested them all ways advised and found no more than 1-2Mv of DC offset.  This was with DAC sitting by itself on my workbench, plugged in by itself, with volume at all the way down, and then also at 80% max.  This was without a source signal.  If I were to apply a source signal to the DAC, it would be most convenient to grab my old Rotel CD player and plug it in.  Is this OK to do, since it is not a stand alone transport?