[outlawrocketman]

Hi all, having what I think is a problem with my DAC-60. I've removed all the other variables that I can think of (computer source, amp, speakers). This morning I'm only getting sound from 1 of the two channels. Input is COAX, output to RCAs of my amp.

I opened up the DAC-60, thinking maybe one of the tubes had burned out. Both tubes are glowing from two internal points.  I'm not much of a tube person though - could they glow and still not be functioning? Any other thoughts on what the problem could be?

Thanks in advance.

[Rasta]

Try swapping tubes between channels and see if the problem follows the tube.

[outlawrocketman]

Hmm, great idea. Switch the tubes but the problem stayed put - right channel has much, but not the left channel.

[outlawrocketman]

Hmm, I put in a headroom to take the USB to RCA, cutting out the HAGUSB (USB to S/PDIF) and the DAC-60, and I have both channels. So it's either the HAGUSB or the DAC.

[BradJudy]

Can you connect the DAC-60 to something like a CD/DVD player to confirm that the problem lies in the DAC?

[HAL]

Agree with Brad about checking with a different source S/PDIF input.

Next, I  would check the tube socket on the side with no output.  The contacts might not be making good connection to the tube pins. 

Another possibility might be the wire to the RCA output connector has a bad solder joint at the jack or the PC board. 

[outlawrocketman]

Agreed about the next steps. I'll have to order a cable so my laptop's mini optical out can get to the DAC S/PDIF optical in. That would switch me from coax in and eliminate another variable as well.
Since I swapped the tubes between the tube sockets I don't think that's the problem.  I'll check the DAC overall to see if there are any solder problems.

[outlawrocketman]

I got an optical S/PDIF cable to allow me to test connecting my laptop directly to the DAC-60, removing the HAGUSB from the chain. This also removed the coax in on the DAC-60 from the chain. 

The problem continued with this configuration.

So, what I know:
The problem is in the DAC-60
It is after the inputs (S/PDIF and Coax)
It is not the tubes

I visually inspected the innards of the DAC-60) without taking apart any internal components, and did not see any bad solders or obvious problems.

Any other thoughts on debugging?

Thanks much.