Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
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)
| Reason: Not specified
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921  Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
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?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA
Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
|
Is this a new build, or was it working then failed?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
It was working, then failed.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
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 ?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
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?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
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.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
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?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
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.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
Well, for sure if anyone can, Russ can tell.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA
Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
|
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 255 time(s).You cannot view/download attachments. Try to login or register.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
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)
| Reason: Not specified
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
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?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
Certainly not. Try disconnecting what ever comes after the legato.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
I have disconnected everything including HP and it still has continuity between SE and Ground connection for output.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
Ohh - remember the relay.
Its there for doing this one purpose - shorting the SE to GND when the Legato is not powered.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA
Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
|
Try measuring continuity between output and GND with the power on (on the non-functioning channel).
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 9/16/2011(UTC)
Posts: 85
Location: Wisconsin
Thanks: 1 times
|
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA
Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
|
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.
|
|
|
|
|
|
Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.
