I'll check that.
By the way, I'm gonna explain how the left channel died.
First it didn't work but after I moved the rca (in both sides sound card and amp) it worked, I thought could be the cable or I wasn't connecting the cables firmly (that was my thought), then when I was about to add the cables for the subwoofer, it finally died, no more audio on the left channel.
"The headphones have the same problem, only the right channel works."
I suppose a malfunction of the input circuits - poor contact, RCA jacks, switches, volume control or telephone amplifier.
I suppose a malfunction of the input circuits - poor contact, RCA jacks, switches, volume control or telephone amplifier.
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A common issue on some RCA jacks is a deformation of the inner contact that should touch the central pin. I've replaced several jacks with this issue, and also found the issue on brand new connectors imported from China. It is very easy to check if you have this issue. Disconnect your RCA cable from the source and measure the resistence between the ground and the central pin on the faulty channel. If the bad contact is confirmed, try a RCA cable with expansion type connectors.
I checked the ohms in both channels in RCA and speakers and have the same values.
I also tried with a plastic to see if there's anything loosy but doesn't seems to be the case.
Maybe the potentiometer is broken?
I also tried with a plastic to see if there's anything loosy but doesn't seems to be the case.
Maybe the potentiometer is broken?
You need to rule out upstream and RCA connection issues.
Try this:
Connect old throw away speakers.
Connect right RCA. Play music. Ensure sound is good.
Disconnect right RCA and plug it into the Funk left RCA in. Play around with the RCA connection. Slide it in slowly and out slowly. Rotate it. Wiggle a bit. When or if you get sound note what you did. Try and reproduce it. Try different RCA cables.
Try this:
Connect old throw away speakers.
Connect right RCA. Play music. Ensure sound is good.
Disconnect right RCA and plug it into the Funk left RCA in. Play around with the RCA connection. Slide it in slowly and out slowly. Rotate it. Wiggle a bit. When or if you get sound note what you did. Try and reproduce it. Try different RCA cables.
If you followed the previous suggestions and the amplifier is still defective, I believe that a easy fix is unlikely and the attempted repair will require tampering with the device. I would contact the seller and/or manufacturer and evaluate the options. They may be better than you think.
I did that already, different cables, different dacs, switching from headphones/speakers.
You are right, probably is the potentiometer that is broken or something else,
I already contacted Burson, $300 lost for testing a unit, what a shame.
You said both amps (main and head) are only 1 side working meaning that the signal is interrupted in the common part from input to the buffer after the volume control. This is also where the opamps are working.
I guess one of the opamps might be damaged or not well inserted or has loosened from the base because of vibrations during transport.
So pull the amp of the dead channel out and substitute it with a NE5532 or similar and check all traces which are accessible.
I guess one of the opamps might be damaged or not well inserted or has loosened from the base because of vibrations during transport.
So pull the amp of the dead channel out and substitute it with a NE5532 or similar and check all traces which are accessible.
I firmly pushed both op amps, I replaced the one close to the RCA inputs with one that I know was working properly (that one came with my Sound Blaster AE-9) and I got the same behavior.
I didn't touch the other OP amp because I think is intended for the headphones.
Off topic, anyone knows if Rega io amp is any good?
You can operate the amp without the opamp, nothing can be damaged, to see which channel is amplified by it. There are no schematics available so we do not know what the opamps are doing.
A good guess of yours is the volume pot try to touch the slider connections with a needle or your finger and see if some hum is heard.
The second opamp is probably not from the phone amp because it says discrete semis.
A good guess of yours is the volume pot try to touch the slider connections with a needle or your finger and see if some hum is heard.
The second opamp is probably not from the phone amp because it says discrete semis.
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Here's the manual
Burson Funk User Manual V1.5.pdf - Google Drive
At page 6, you can see that there's an OP AMP that says Input Buffer Stage Dual Opamp, that's the one I changed.
The other one says Headphone Amp Voltage Gain Stage Dual Opamp.
I'll try to do the potentiometer test.
Burson Funk User Manual V1.5.pdf - Google Drive
At page 6, you can see that there's an OP AMP that says Input Buffer Stage Dual Opamp, that's the one I changed.
The other one says Headphone Amp Voltage Gain Stage Dual Opamp.
I'll try to do the potentiometer test.
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I received the second unit, what a shame, similar problem with the left channel.
This time the left channel works but sometimes (when is cold) either makes pops, white noise then pops again, or gets silent.
The first 24 hours it did lots of pops, then white noise, then pops again.
Today, on my second warm up, it worked for a few seconds, then got muted for about 30 seconds, then the sound came.
When is cold the left channel doesn't seems to work properly, when is warm (about 4 minutes) then the issues are gone.
This time the left channel works but sometimes (when is cold) either makes pops, white noise then pops again, or gets silent.
The first 24 hours it did lots of pops, then white noise, then pops again.
Today, on my second warm up, it worked for a few seconds, then got muted for about 30 seconds, then the sound came.
When is cold the left channel doesn't seems to work properly, when is warm (about 4 minutes) then the issues are gone.
This time I turned off the amp for about 30 minutes. After turning on, I only got a few pops in the left channel.
So I think if it gets really cool, then more issues appear, Kind of like has to be warm in order to work properly.
So I think if it gets really cool, then more issues appear, Kind of like has to be warm in order to work properly.
"Has to be warm in order to work properly " --heat on metal parts causes expansion which then makes contact ,solder is a fusible alloy.
After talking with burson sales department, they told the to switch the op amps, I swaped the V6 with the IC ones and no more issues.
So this time the issue was the OP AMP, I'm still doing more test but for now that seems to be the problem.
So this time the issue was the OP AMP, I'm still doing more test but for now that seems to be the problem.