Pioneer RX-570

[DanThrax]

Good afternoon,

My lovely better half has a Pioneer unit which has worked flawlessly for almost 3 decades. After our recent move to Germany from the US, the rear speaker outputs have quit. Tried every speaker setting on every connected device, and swapped out every single speaker, still no rear sound. Pulled the cover off, and tried to blast the dust off every exposed surface; no dice. Everything works, except for the rear speakers. Where should I check first?

 

[tunzafun001]

I had a similar issue with a Sharp branded unit. Blew out the dust, wiggled the mosfets with heatsinks attached. Good as new. Probably a bad solder joint in my case.

 

[DanThrax]

"mosfet?" You mean "Moss Fett," Boba's less-than-famous uncle?

 

[kellys_eye]

Post clear pics of the unit and the area of concern.

@tunzafun001 probably referring to the output semiconductors (MOSFETs) that are both soldered to the main board and bolted to large heatsinks. If the unit was disturbed (banged) in transit then the weight of the heatsink may have dislodged the MOSFET connections - the resultant 'loose' solder joint causing a loss of audio.

It's a good possibility and it only takes a (very) close look to make a determination.

 

[Harald Kapp]

Look up loose or cold solder joints. Often easily identified, as @kellys_eye noted.
Simple to repair: heat the solder joint with a soldering iron, preferably adding some fresh solder with a flux core.