Expert: Cleggsan - 9/26/2010

Question
My ADCOM GFP-555 Preamp has RCA Plugs for R & L channels for "MAIN OUTPUTS" to amp. Before inserting the R & L channels into my amp I checked for a short between the two cables. I got continuity between the tips of the R & L RCA plugs. Is this normal (O.K.)? The continuity (short?) must be in the preamp as the cables are not touching.  

Answer
Did you test the two audio cables independently?  Are they okey?  If so you should not be afraid to connect them up to the outputs of the preamp and the inputs of your power amp.

Why did you make this test?  Are you worried about it or do you suspect the audio is not in stereo?   There must be a reason why you checked this very odd situation.

What kind of ohmmeter did you use to check the resistance between the R and L outputs of the preamp?  If the power is OFF the dc resistance might be very low, but not zero, if the output transistors or ICs have lost their bias.  With the power on the resistance would change a little.  If you are using an ohmeter with large internal battery you can do damage to the output circuit inside the ADCOM!  Hope you didn't mess it up.

I wouldn't worry about it.  If you pulled a schematic diagram of the output circuit of the ADCOM it is probably clear how the resistance could be low.  It is most  likely working properly.