Help, left speaker keeps going out!

[tetsuodaironman]

So, I replaced my speaker wire because the left speaker kept going out. I would have to adjust/move the wire around to get it to register again. I ended up buying more speaker wire and it's doing the same thing! Could it be the contacts on the receiver (old Technics receiver)? I am just tired of having to get up and move the wire because it cuts off often...like every ten minutes, but sometimes I am lucky and both speakers will work for an hour. Any suggestions would be awesome!

[kjkenney]

do you have another speaker to try on that channel? that way you can rule out if its the speaker or the receiver. If the receiver's the culprit then yeah I would imagine its just dirty and you could use some contact cleaner to freshen it up, or the contact points for that channel could be loose in there. May just be the speaker though, in which case its not the worst but still annoying that you would have only one half of a pair that works =\

[Tardcore]

swap the speakers around to make sure the problem is actually the speaker and not the receiver.

[allenh]

Could it be the contacts on the receiver (old Technics receiver)?

 

If the fault doesn't swap sides as Tardcore suggests it is likely to be the output electrolytic capacitors.

 

If if does change sides and the speakers are old as well it well be a similar problem but this time the electrolytic caps in the crossover inside the speaker.

 

Capacitors dry out when they get old and the large output ones in an amplifier are always likely candidates for this sort of thing.

[xxmartinxx]

What is the model number of receiver?  What kind of speakers (with model number).  

 

This is most likely an issue with the speaker wire not making proper contact at either the speaker or receiver end.  I don't think it's electrolytic caps.  They don't normally exhibit this type of behavior.  

[allenh]

What is the model number of receiver?  What kind of speakers (with model number).  

 

This is most likely an issue with the speaker wire not making proper contact at either the speaker or receiver end.  I don't think it's electrolytic caps.  They don't normally exhibit this type of behavior.

It might not be the caps in this particular case but its quite likely, this is one of the symptoms of drying electrolytics. They can sound like you have a dry joint or bad connection just like has been described and as the temperture changes the dielectric inside changes and they can effectively go open circuit and as the OP stated it was an old unit its quite possible. The same can happen with the crossover caps but here you tend to loose only the high or low not usually both.

That said Tardcores suggestion about swapping sides is a good one to identify where the problem actually lies first.

[xxmartinxx]

I've never seen bad electrolytics cause an amp to completely cut out.  Normally, you'll get humming, loss of power or bass, but not cut out entirely.   In severe cases, they might actually pop and smoke, but that's not subtle.  Based on the fact, it works/doesn't work if he moves the cable indicates it's most likely a bad connection/solder joint somewhere.

[allenh]

I've never seen bad electrolytics cause an amp to completely cut out.  Normally, you'll get humming, loss of power or bass, but not cut out entirely.   In severe cases, they might actually pop and smoke, but that's not subtle.  Based on the fact, it works/doesn't work if he moves the cable indicates it's most likely a bad connection/solder joint somewhere.

 

I've seen it a few times, If the power supply ones do it then you loose the lot for a while but if an output one does it you just loose one channel.

 

I've just re capped a HK power amp that was doing exactly this on one side after it warmed up and acted very much like a dry joint so you could tap the side of the case and it would come back and then drop out again after a while, I re-soldered all the joints as a matter of course and it still did it, replaced the output caps and it was fine. As I say the dialectic breaks down inside and they drop out just like a dry joint or bad connection, the larger the device the more chance of it doing it I find.

 

I've also had a pre amp where the through plating on the board was no good so the top pad and track under the cap were not soldered and it gave pretty much the same symptoms but as this is an old amp that's very very unlikely, it will either be electrolytic break down or as you say a bad joint/connection somewhere in the output section but like all these things without being able to see or hear the fault it's next to impossible to diagnose with any certainty.

[xxmartinxx]

I think your instance of the cap shorting out is rare.  I think, regardless if it's a bad solder joint or a blown cap, this thing is probably garbage since I assume this guy doesn't own a soldering iron, or what to do with one.  I doubt he wants to pay a bench fee to have it looked at.

[tetsuodaironman]

Thanks, guys. It is just the one channel that keeps going out. I am going to swap the speakers out and report back. I do own a soldering gun if it comes down to resoldering any joints.