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Topping D50s Fault - Right Channel Broken Above 6Khz

Berwhale

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I found some time to play with REW today with a view to trying the moving mic measurement technique. However, when I started doing to some test sweeps, I noticed that right channel on my Topping D50s appears to be broken. Here's what I see in REW (Blue is right speaker driven by right channel, brown is right speaker driven by left channel)...

Topping D50s Right Channel.jpg


As you can see, the output takes a nosedive after 6Khz. I repeated the test with the left speaker and I got similar results. After some further investigation, I found the right channel would pop and go silent when a test tone hit 6,154Hz pretty consistently. It's as if the right channel turns itself off when it reaches this frequency.

I have noticed the odd pop when using my system over the past few days, however i've also been playing with Voicemeeter and some VSTs, so I had dismissed this as a consequence of my semi-competent fumbling with the windows audio pipeline.

Does anyone have any thoughts on what the problem could be and if it would be fixable? I purchased the DAC in August 2019 from ShenzenAudio via Aliexpress, so my chances of getting it back to China are pretty slim.
 

mansr

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I'd start by opening the case and looking for anything obviously wrong. If you post a photo of the PCB, maybe someone will spot something.
 
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Berwhale

Berwhale

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I'd start by opening the case and looking for anything obviously wrong. If you post a photo of the PCB, maybe someone will spot something.

I can't see anything obvious...

20210410_142625.jpg
 
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Deleted member 2944

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You need to utilize REW and test the unit directly.....without any acoustic measurements.

Dave.
 

mansr

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As you can see, the output takes a nosedive after 6Khz. I repeated the test with the left speaker and I got similar results. After some further investigation, I found the right channel would pop and go silent when a test tone hit 6,154Hz pretty consistently. It's as if the right channel turns itself off when it reaches this frequency.
Does the left channel keep working when this happens? Does the right channel recover if you lower the frequency, or does it require a power cycle?

I can't see anything obvious...
No, nothing looks obviously fried.

If it's a fault, as opposed to a design flaw, I don't imagine it would be too difficult to locate it. How are your oscilloscoping skills?
 
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Berwhale

Berwhale

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Berwhale

Berwhale

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Does the left channel keep working when this happens? Does the right channel recover if you lower the frequency, or does it require a power cycle?

No, nothing looks obviously fried.

If it's a fault, as opposed to a design flaw, I don't imagine it would be too difficult to locate it. How are your oscilloscoping skills?

It behaves very similarly to issue described by @LarsS and others in D50 thread. If I switch REWs output to the left channel and back, it re-enables the right channel.

If the issue was just with REW, then I could probably live with it. However, I'm certain that i'm hearing similar pops during normal music playback.

I haven't used an oscilloscope since using one to find a break in some thin Ethernet co-ax in college :)
 

mansr

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Skimming that other thread, it seems like it was determined to be caused by the automute being configured incorrectly. That's no fun at all. I was hoping for something much more bizarre. Did they release an updated firmware to fix it?
 
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