Hi-fi Speaker Not Working Initally

[Meehael]

Hi everyone,

I've noticed recently that my right speaker doesn't work when turning on the amp and playing music. Only after I turn up the volume it cracks to life and starts working normally.
After coming to life, I can then lower the volume again, and the speaker will continue to work normally.

Nothing changed in my setup for years.
I also tried disconnecting the speaker from the amp, cleaning the dust on the connectors and cable ends, and reconnecting it, but it didn't help.

Any ideas, please?

Amp: Yamaha A-S501
Speakers: Dali Opticon 6
Music source: PC with ASUS Xonar AE

Thanks in advance,
Mike

 

[Muadib]

Did you try swapping the speakers to see if the trouble is with the amp or the speaker?

 

[Meehael]

I have swapped the speakers now and now the other speaker doesn't work.
PS: I had to wait until morning to test this, because it doesn't happen immediately. As if it happens only on cold start.

 

[Muadib]

Then it’s your amp. Hopefully it is still under warranty.

 

[Meehael]

OK, thanks, Muadib

 

[rickon66]

If you have an analog volume control, it sounds like oxidation on one channel of the control.

 

[Meehael]

Yes, it's analog.
OK, thanks, Rickon.
So I guess, there's nothing I can do myself, but to take it to the repair shop.
It's four years old and out of warranty.
On the other hand, it's not broken, just annoying, so I could live with it for some time more, until it breaks completely.

Thanks again, guys

 

[Jimminy]

You could try spraying some contact cleaner inside the control potentiometer. Spray a short burst, rotate the control back and forth, then spay another burst. Repeat if it's a ganged control til you clean each section.There are some formulations just for this purpose. I think they also have a very light lubricant (left in the residue). Stuff that's sold as "tuner" cleaner might woirk as well. Check at an electronics supply house or parts store.

I've had good luck fixing scratchy controls. If the pot is very worn though, you'll eventually have to replace it.

Good luck.

 

[biostud]

My amp has the same problem (also right speaker), when it hasn't been used for some time. But it is +20 years old

 

[Thump553]

My amp has the same problem (also right speaker), when it hasn't been used for some time. But it is +20 years old

Both of you should try Jimminy's advice. It's simple to do on most equipment (just pull off the volume knob and spray around the base of the shaft. If the problem is crackly or intermittent sound when you turn the volume knob you have a real good chance of that fixing it for a few bucks. I've done it a few times in the past with great results.

 

[Meehael]

You could try spraying some contact cleaner inside the control potentiometer. Spray a short burst, rotate the control back and forth, then spay another burst. Repeat if it's a ganged control til you clean each section.There are some formulations just for this purpose. I think they also have a very light lubricant (left in the residue). Stuff that's sold as "tuner" cleaner might woirk as well. Check at an electronics supply house or parts store.

I've had good luck fixing scratchy controls. If the pot is very worn though, you'll eventually have to replace it.

Good luck.

OK, that sounds like a thing worth trying out, thanks Jimminy.

 

[biostud]

Both of you should try Jimminy's advice. It's simple to do on most equipment (just pull off the volume knob and spray around the base of the shaft. If the problem is crackly or intermittent sound when you turn the volume knob you have a real good chance of that fixing it for a few bucks. I've done it a few times in the past with great results.

I'll do that next time it stops working.

 

[Meehael]

Update:

Hey guys, just wanted to let you know that I've managed to fix it.

I've finally found time yesterday to try to repair it.
What I did was to remove the cover, vacuumed the dust as much as possible, disassembled front circuit boards, disconnected them from the main board, removed front knobs, and put them back together... Just the basic layman disassembly.
Didn't use any cleaning fluids or solutions.
After assembly, it works normally.

So, thanks again everyone, you were really helpful

 

[mindless1]

^ Glad it's working for now, but odds are that this is only temporary.

It is most likely that the volume potentiometer(s) have some aging, whether it is loss of springiness on their wiper arms, or hardened grease, or oxidation.

A de-ox spray, especially one made for audio/pot cleaning is ideal, or DIY spray whatever, or take the pot apart to clean and bend a "little" more tension in the wiper arms, or replace it with something higher quality like a conductive plastic alps pot... keep in mind, it does not have to fit on the PCB, just have clearance away from the PCB then you can air-wire the contacts to the PCB pads. If that section of the PCB has no purpose other than soldering a POT onto it, you can even cut off the PCB for more clearance and air-wire to the end of the cut off portion.

I know that's kind of vague, really has to be taken on a case by case basis, what will work within the available space and how much effort to put forth.

Also keep in mind that with a PC as the source, that gives you variable volume so you could even replace the volume pot with a resistor divider and just use the PC to control volume.

 

[Meehael]

Haha, you're right. It has already returned to the previous state, only after one day of working.
I guess I'll have to try to take the volume potentiometer apart and clean/replace it.

Thanks again!

 

[Thump553]

Going to have to open my living room receiver as well. I moved the balance knob the other day-probably for the first time in more than a decade and the right channel kept popping in and out. Unfortunately that knob doesn't pull off so it looks like I will have to open up the receiver.

BTW I ran across what looked to me like a pretty decent guide on what to use and how to do it. A warning-the current prices for everything listed in the video are roughly double what was shown there just two years ago. Welcome to the modern economy I guess.

 

[mindless1]

There are things you can try before buying a can of cleaner.

- Gently heat it with a hair dryer (might be old, hardened grease)

- Brake Cleaner or lighter fluid (again, might be the grease, be sure to rotate the pot back and forth several times while the fast drying brake cleaner is still wet... lighter fluid, you have more time to work with). The more popular version of Deox is naptha (lighter fluid) plus 5% oxalic acid.

I'm not suggesting buying these things to save a buck but if you have them already... worth a try... even a few drops of gasoline in a syringe, can get old (petroleum) grease degunked, or WD-40... you can try many things before accepting defeat and buying a cleaner or taking the pot apart, but note the compatibility with nearby plastics. Some petro grease solvents like acetone, brake cleaner, or even gasoline, aren't safe for all plastics, especially acrylic site windows in audio gear which might get cloudy from the fumes, let alone direct contact.