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I've got a Legato that has one channel not producing sound. I checked the connections today and all looks good. I also hooked up a small set of headphones (as I set it up to be able to do that) and both channels are working. Any chance I missed something? Edited by user Monday, August 3, 2015 1:59:35 PM(UTC)
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Originally Posted by: mjock3  I've got a Legato that has one channel not producing sound. I checked the connections today and all looks good. I also hooked up a small set of headphones (as I set it up to be able to do that) and both channels are working. Any chance I missed something? Hi. Pls. explain how?
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Is this a new build, or was it working then failed?
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It was working, then failed.
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If you by saying
"I also hooked up a small set of headphones (as I set it up to be able to do that) and both channels are working"
are sure that the Legato is working - it's time to look upstream.
Lets start real basic. Are you sure that you're feeding the DAC both left and right channel ?
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To be honest I have no idea how to check for that. Wouldn't the fact that I can hear both channels using the headphones connected to the HP 1, 2, 3 output of the Legato mean that I have 2 channels of the DAC working?
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Ok, now I understand. So you actually can hear music through the HP connector.
Then I would look upstream (to whatever comes after the Legato). The HP connector is in parallel with the SE outputs.
Of cause you could alway look for bad solder joints and/or bad wiring.
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Checked out the solder joints & wiring. It looked fine. Am I reading the schematic right that R25 and L1 are on the outputs but not HP output?
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I don't think so. I think it's connected as this. (I could pull the board from my rig - but if your board is in "free air" you might trace the HP output) avr300 attached the following image(s):  cut.jpg (27kb) downloaded 12 time(s).You cannot view/download attachments. Try to login or register.
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Well, for sure if anyone can, Russ can tell.
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Both the SE Outs and the HP Outs go through L1/L1 and R25/R26. They are they same net, just in a more convenient spot for connecting three wires for headphones.  Edited by user Friday, August 7, 2015 7:33:13 PM(UTC)
| Reason: Not specified Brian Donegan attached the following image(s): Legato_SE.jpg (131kb) downloaded 254 time(s).You cannot view/download attachments. Try to login or register.
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Thanks for the input, avr300 & Brian. If I put the meter on the output screws I still get nothing, now on both channels. this would rule out wires and jacks, correct? Edited by user Saturday, August 8, 2015 3:45:18 PM(UTC)
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Just checked and I got continuity between hp output and SE output. Something that puzzles me is I also get continuity between SE and Ground at output. This shouldn't be should it?
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Certainly not. Try disconnecting what ever comes after the legato.
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I have disconnected everything including HP and it still has continuity between SE and Ground connection for output.
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Ohh - remember the relay.
Its there for doing this one purpose - shorting the SE to GND when the Legato is not powered.
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Try measuring continuity between output and GND with the power on (on the non-functioning channel).
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I'm not ignoring you, just an incredibly busy week at the day job.... :) I am a little confused about the symptoms, so I want to clarify the situation: - One channel not working: balanced output, SE output, or both?
- You hear sound from both channels at the headphone output? This means that both channels are working through headphones, but not through the other outputs?
The resistance check I had you do was to confirm that the relay was not keeping the output shunted to ground when operating. It was 30-ohms, not 0-ohms, so you should be okay there.
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