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Speakers make a loud noise when turning off. Is there a way I can eliminate it?

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Does this happens even when the audio volume knob is set to the minimum level? If yes, once it has in built amplifier, without knowing anything about its circuitry, there is no much to do.
 

Does this happens even when the audio volume knob is set to the minimum level? If yes, once it has in built amplifier, without knowing anything about its circuitry, there is no much to do.

Yes, this happens even with the volume turned all the way down.

I can open it up and take photographs of the circuit and post it here, will that help?
 

I can open it up and take photographs of the circuit and post it here, will that help?

It is necessary to have the circuit diagram of the equipment; perhaps others here can have some general insightful tip to overcome this problem, but at least for me, I don't know how to do another way.
 
It is not the speakers, cause is in the amplifier that feeds it/them.
Happens on both ? Is it a recent behavior or were like that since new ?
Ask the manufacturer customer service.
 

It is not the speakers, cause is in the amplifier that feeds it/them.
Happens on both ? Is it a recent behavior or were like that since new ?
Ask the manufacturer customer service.

It has been that way since new. (But I was suspicious if it is a used one)

Those are active speakers, amplifier, etc is in the sub-woofer.

Where I bought it and live, there is no official customer care available, I have to contact their international cc and they said something like it is normal and they'll take it as feedback.
 

I think you already have your answer. Unless you:

1) Redesign the amp, or
2) Buy a different speaker

you are going to have to live with this.

They said it's normal but to me it is disturbing. You have no idea how loud it is, and how disturbing it can be in night.

Can't I remove cheap parts and put in nice parts and make it go away? If I post pics of PCB, etc, will any of you here be able to help me?
 

Since the loud pop is heard in both channels, it suggests a power supply problem. (Whereas if it were in only one channel, then you could try switching components between them in an effort to track down the problem.)

I imagine it comes from a sudden drop (or jump) in DC volt level when power is shut off. Possibly a capacitor discharging, or reversing its charge, etc. It may go through all stages of the amplifier, or merely the final power output stage. Then to the speakers.

When servicing an old unit some technicians routinely replace capacitors, electrolytic type especially. They're prone to develop problems over the years.

Are you able to check condition of large capacitors in the power supply?
Condition of diodes, etc.? A proper test (in many cases) requires that you disconnect a component from circuitry.

Or else are you able to run the amp from a different power supply?
 
The manufacturer has already said this is normal operation. There is no “problem” other than, perhaps, a bad design. Checking caps and diodes is a fool’s errand. It most definitely has something to do with capacitance as caps discharge on power-off and voltages throughout the circuit change unconcontrolled.
 

Since the loud pop is heard in both channels, it suggests a power supply problem. (Whereas if it were in only one channel, then you could try switching components between them in an effort to track down the problem.)

I imagine it comes from a sudden drop (or jump) in DC volt level when power is shut off. Possibly a capacitor discharging, or reversing its charge, etc. It may go through all stages of the amplifier, or merely the final power output stage. Then to the speakers.

When servicing an old unit some technicians routinely replace capacitors, electrolytic type especially. They're prone to develop problems over the years.

Are you able to check condition of large capacitors in the power supply?
Condition of diodes, etc.? A proper test (in many cases) requires that you disconnect a component from circuitry.

Or else are you able to run the amp from a different power supply?

The manufacturer has already said this is normal operation. There is no “problem” other than, perhaps, a bad design. Checking caps and diodes is a fool’s errand. It most definitely has something to do with capacitance as caps discharge on power-off and voltages throughout the circuit change unconcontrolled.

I'm getting a voltmeter, soldering rod and desoldering pump, should these devices be enough to troubleshoot this problem? Because I really want to resolve this problem, I'm new to electronics and have never soldered before, by posting pics will you any of you be able guide me through the process and what new parts which I should buy to replace on the amp? Thanks
 

With no electronics knowledge nor soldering skills, you will end replacing the 'turn-off-noise' with smoke. Abstain to guess.

Ask them to fix it / reveal any recalls / update design / modification / cures ----> https://swanspeakers.com/service/

Last resource; install switches that will turn off the transducers before powering off.
 
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Why do you keep on insisting that with your admitted limited knowledge of electronics that you are going to "fix" this? We've already established that the problem is in the design, not a defective component. Are you going to redesign the amplifier? Maybe you should just buy some ear plugs.
 

With no electronics knowledge nor soldering skills, you will end replacing the 'turn-off-noise' with smoke. Abstain to guess.

Ask them to fix it / reveal any recalls / update design / modification / cures ----> https://swanspeakers.com/service/

Last resource; install switches that will turn off the transducers before powering off.

Why do you keep on insisting that with your admitted limited knowledge of electronics that you are going to "fix" this? We've already established that the problem is in the design, not a defective component. Are you going to redesign the amplifier? Maybe you should just buy some ear plugs.

Because the problem is that annoying and the money spent on these speakers is literally wasted if I can't use it, which is the case because of this problem.

I'm also curious about tinkering with electronics, so I want to try my hand with at it.

Is it impossible to redesign the amp by myself with help from this board? What would be the cost of the parts, etc?
 

If you are turning off with a mains switch a 0.1uf cap across the switch can often solve the problem, its a common issue when mains is switched directly.
 

Several options are possible.

1) Never turn off your amp - just reduce the volume to zero.
2) Install an additional on/off switch on the DC supply output . Switch this off before switching off the mains switch.
3) Have a separate switch which disconnects the speakers - one wire per speaker is enough. Switch this off before the main switch is toggled. However since this is a 1+2 speaker system, this may be too complicated.
4) Replace the mains switch with a DPST switch - where one set of poles is for mains (as before), and the other is for the DC supply output (as described in (2) above). This way both switch's are combined and will work together. A 4PST switch is even better, since it is always advisable to disconnect both mains wires when not in use.

See which of the above works for you. I believe (4) should solve your problem, while (1) is the easiest to do.
 
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