I have a problem with the receiver for my 5.1 system.
When I turn it on, the speakers start making a popping sound that continues for a few minutes. I have tried disconnecting the speakers and using different ones, as well as different inputs, but the issue remains the same. The popping lasts for a shorter time if the receiver has been turned off for a while. Initially, it only lasted a few seconds, but it has gradually got worse.
Watch the video to hear the sound. In the video, I have only connected one speaker.
The receiver is a Marantz NR1501. I'm not sure when I bought it, but I found a review from 2010.
I opened the receiver and inspected it, but I can't see anything burnt, and all the capacitors look OK.
Do you have any idea what the issue is? How can I confirm if that is the root cause?
You're going to have a hard time pinning this down to a specific component without a circuit diagram. I did find that there's a service manual for this unit: https://elektrotanya.com/marantz_nr1501_ver.5.pdf/download.html
Seems to be legitimate and has diagrams.
I would recommend starting on the output side - is the popping present on every speaker output? Both left and right? Use a very simple speaker for this, one that doesn't require its own power source, just a red and black wire. Also, is the popping present with no input audio?
If you can narrow it to a certain output you can backtrack it to a specific section of the circuit that feeds that output. Alternatively, if it's present on all outputs then it must be a component that is common to all, and therefore behind the area that splits to the different outputs.
An oscilloscope would be handy - you could identify the faulty signal at the speaker output, then check points along the path backward. Half-splitting is your friend. You don't have to buy an expensive piece of lab equipment, a cheap $30-40 digital oscope will be good enough.
Another option would be to throw parts at it. I see units listed for parts on eBay for ~$80. You could try swapping out circuit boards one at a time.
Thanks, I have looked on the service manual and does diagrams seems to match the actual boards in the receiver so it will be possible to use for fault tracing.
The popping could be heard on every speaker one my 5.1 system but the receiver is 7.1 so I could try the last two outputs.
I don't own any oscilloscope but I'm could buy one to try to find what the issue is.
I don't live in US so the shipping would be too much to be worth it, but on a local website someone posted a NR1501 receiver earlier today so I could try that.
Yeah if you're down to put the effort into fault tracing, you'll need an oscope. Something like this: https://ebay.io/m/PDLGdu will work fine.
It will take some time, but if you're lucky you'll find it's just a capacitor that you can replace cheaply. If you're unlucky you might find that it's a faulty IC, in which case you might have to replace an entire circuit board from a donor unit anyway.