Hoping someone on here may have some experience with Marantz AVRs. I have a NR1608 AVR (it's the half-size 7.2 AVR) and everything works perfectly except for distortion (kind of crackling, static pulsing distortion), which gets louder as you increase volume on the front left (FL) channel.
I called Marantz and they recommend service to replace the HDMI board, saying it's a digital chip failure, most likely.
I question this for two reasons
1) they want $300 for the HDMI board - and it's not worth that much working
2) I have put analog audio through to the CD and DVD channels and have the exact same distortion
- looking at the service manual, it appears this would eliminate the HDMI board from the signal path, since I'm not using any DAC chips
- as a first thought, and since I could get to it without removing the HS/Amp Board, I did check the input capacitor, 47uF 50V and tests fine with 0.6r and 0.8% Vloss at 45uF
I guess my questions are
Trying to get a game plan before I spend 20 mins tearing it all apart to get the HS/Amp board out.
Attached is the amp board section of the service manual.
Paul
I called Marantz and they recommend service to replace the HDMI board, saying it's a digital chip failure, most likely.
I question this for two reasons
1) they want $300 for the HDMI board - and it's not worth that much working
2) I have put analog audio through to the CD and DVD channels and have the exact same distortion
- looking at the service manual, it appears this would eliminate the HDMI board from the signal path, since I'm not using any DAC chips
- as a first thought, and since I could get to it without removing the HS/Amp Board, I did check the input capacitor, 47uF 50V and tests fine with 0.6r and 0.8% Vloss at 45uF
I guess my questions are
- is it worth trying to remove and test the input pair (A992), I have matched pair as a replacement on hand, or experience with other caps in the audio signal that could be the problem
- is it possible the outputs are noisy (2SD2390/2SB1560)
- what would you suggest - it is quite difficult to get to test points with the O-scope while it is powered on.
Trying to get a game plan before I spend 20 mins tearing it all apart to get the HS/Amp board out.
Attached is the amp board section of the service manual.
Paul
I think you can safely discount the Marantz service advice, they just want to charge you as much as possible.
You need to get the oscilloscope out and trace the noise through the circuit. First check the input to the power amplifiers. Is it noisy? You don't need to pull everything part to do that.
Don't start changing parts willy-nilly, you'll just make the problem harder to solve.
You need to get the oscilloscope out and trace the noise through the circuit. First check the input to the power amplifiers. Is it noisy? You don't need to pull everything part to do that.
Don't start changing parts willy-nilly, you'll just make the problem harder to solve.
