Pioneer SX-828--massive pop when low filter is flipped

[EastPoint]

I have a Pioneer SX-828. When you flip the low filter to ON, you get a major pop through the speakers. When you flip it back to OFF, you get an even louder one, and you hear a relay click, and the receiver goes silent for a few seconds before it comes back on. Is this likely to be a switch issue, or a capacitor issue?

 

[petehall347]

likely a capacitor leaking in the filter circuit ..is it both or just one speaker ?

 

[EastPoint]

Just the left speaker, and it doesn't matter which way the balance is set--left, right, middle. Always a huge pop in the left speaker.

 

[petehall347]

i would suspect c37 first .then c31 .then q7
it could of course be something else .

 

[EastPoint]

There's a thread here:
http://forum.allaboutcircuits.com/newsgroups/viewtopic.php?t=30943
where someone had the same problem and was able to fix it by replacing two capacitors. Are those the ones you're talking about? If so, do you know what their ratings are, offhand?

 

[petehall347]

yes the coupling caps

 

[EastPoint]

Do you know what their specs are, offhand?

 

[petehall347]

c31 2.2uf 25v
c37 1uf 25v
c45 3.3uf 25v
that's from the schematic . it may or may not tally up with what's on the board .

 

[EastPoint]

Awesome, thank you.

 

[Ray Gianelli]

I had a friend bring me a Pioneer integrated amp that was doing the same thing. It turned out to be a shorted electrolytic up in the filter switch assembly. It was a real pain to get to, but replacing it fixed the trouble.

 

[jblmar]

Another possibility would be a cold solder on those caps. Check first before desoldering.
Loud pops aren't good for your speakers.:nono:

 

[id78]

Hi. Resurrecting old thread with dead links, that almost matches an issue I have
with my otherwise very lovely and beloved 828.

Periodic, random loud crack/pop.
Volume up or down.
Sitting at idle, no load on it.
Other than that, heh, she is fine.

Same possible source?

Q?
"Coupling caps" described above are on which board?
Schematics of Tuner and AF Unit show cap numbers that go that high.
Thanks.

 

[chazix]

Periodic, random loud crack/pop.
Volume up or down.

Welcome to AK. From your description, I think it's more likely that there's problem in the power amp vs. the problem discussed earlier in this thread.

There is a Pioneer-specific forum elsewhere on AK, where you might want to start a new thread. It might also be worth browsing some of the model-specific threads like the example below, which identify specific components that are nearly certain to cause trouble in this vintage of Pioneer.

http://audiokarma.org/forums/index.php?threads/pioneer-sx-828-find.614821/

Cheers,

chazix

 

[chazix]

Ah, never mind, I see you already found your way to the Pioneer forum.

 

[theapples]

i would suspect c37 first .then c31 .then q7
it could of course be something else .

hello just reached out to you ,