Rattling & Popping Subwoofer when Off

[sstalley]

Hi Everyone,

I searched the forum but have not been able to pinpoint answers to the problem I am experiencing.

I have a Boston Micro PV 90 subwoofer. It has been in storage for 10 years. After plugging it back in, playing music or movies still functions properly without any distortion. My settings are on Auto (power), 80hz, 0 polarity, medium-high volume.

When there is no signal, the subwoofer automatically switches itself off (as it should). However, when it is in its off mode, I experience popping every 3-5 minutes. I then turned the power to "Off" instead of "Auto", and now I hear rattling (1-2 seconds) every 5-10 minutes.

When I turn it back on, and the subwoofer receives an active signal, no more popping or flapping sounds, just good old bass.

What does this mean? It seems bizarre.

Thanks.

 

[MinusTheBear]

Perhaps the subwoofer amplifier is on the fritz.

 

[indulger]

Maybe it's that what-ja-ma-callit, in the amp that's stores the power. When you turn the power off, maybe it's connections are bad and it's making noise where it shouldn't as it releasing it's reserve.
Regardless, the point being, if your amp is making noise like that after being in storage for 10 yrs, I'd think twice about plugging it in. I'd even go as far as to open it up and see if there is any signs of burnt marks. Don't think you have to worry about voiding any warranty

 

[TLS Guy]

Hi Everyone,

I searched the forum but have not been able to pinpoint answers to the problem I am experiencing.

I have a Boston Micro PV 90 subwoofer. It has been in storage for 10 years. After plugging it back in, playing music or movies still functions properly without any distortion. My settings are on Auto (power), 80hz, 0 polarity, medium-high volume.

When there is no signal, the subwoofer automatically switches itself off (as it should). However, when it is in its off mode, I experience popping every 3-5 minutes. I then turned the power to "Off" instead of "Auto", and now I hear rattling (1-2 seconds) every 5-10 minutes.

When I turn it back on, and the subwoofer receives an active signal, no more popping or flapping sounds, just good old bass.

What does this mean? It seems bizarre.

Thanks.

There is a problem in the auto on section and or the power supply. We have had these sort of posts before.

The amp needs replacing. It is dangerous to use it in its current condition. Those switching power supplies are the very devil for nasty fry ups.

The problem is almost certainly a cap some place. The 10 years of storage without repolarizing the caps is what has caused the problem, almost certainly.

The unit is not worth servicing. Your option is to modify it, to take a new plate amp, or recycle it, and buy a new sub.

 

[just-some-guy]

Maybe it's that what-ja-ma-callit, in the amp that's stores the power. When you turn the power off, maybe it's connections are bad and it's making noise where it shouldn't as it releasing it's reserve.
Regardless, the point being, if your amp is making noise like that after being in storage for 10 yrs, I'd think twice about plugging it in. I'd even go as far as to open it up and see if there is any signs of burnt marks. Don't think you have to worry about voiding any warranty

i agree.

they are capacitors.

 

[indulger]

I knew I read that somewhere before. I was just letting him know in non-technical unedumacated layman's terms.

 

[sstalley]

Thank you for your replies. And yes, the unedumacated route was a good call.

So, for an unedumacated person as myself, should I try taking it apart and attempt to fix myself (apartment with baby on board looks difficult to pull off), taking it to a speaker repair specialist (cost effective and realistic or more expensive than finding a used subwoofer replacement?), or riding this baby til it stops working (or will it blow up?)?

Thanks again.

 

[TLS Guy]

Thank you for your replies. And yes, the unedumacated route was a good call.

So, for an unedumacated person as myself, should I try taking it apart and attempt to fix myself (apartment with baby on board looks difficult to pull off), taking it to a speaker repair specialist (cost effective and realistic or more expensive than finding a used subwoofer replacement?), or riding this baby til it stops working (or will it blow up?)?

Thanks again.

First of all using malfunctioning electronics is dangerous, and especially for those switching power supplies in class D plate amps.

You won't fix this yourself, and fixing those switching power supplies is the very devil.

As I said you have two options: -

Recycle that unit and buy a new sub.

Or: - Get a new plate amp from parts x-press and modify your unit. The new unit must make a perfect seal.

There is one more option, to buy a pro amp and connect it to the driver and leave you plate amp in place.

All things considered I would recommend you ditch that sub pronto and get a good new one.

 

[clouso]

Hi Everyone,

I searched the forum but have not been able to pinpoint answers to the problem I am experiencing.

I have a Boston Micro PV 90 subwoofer. It has been in storage for 10 years. After plugging it back in, playing music or movies still functions properly without any distortion. My settings are on Auto (power), 80hz, 0 polarity, medium-high volume.

When there is no signal, the subwoofer automatically switches itself off (as it should). However, when it is in its off mode, I experience popping every 3-5 minutes. I then turned the power to "Off" instead of "Auto", and now I hear rattling (1-2 seconds) every 5-10 minutes.

When I turn it back on, and the subwoofer receives an active signal, no more popping or flapping sounds, just good old bass.

What does this mean? It seems bizarre.

Thanks.

maybe that amp needs just more time to get ''off''...ive experienced that before with the paradigm dsp-3400....and seismic12....when no signal it makes a ''pop'' sound when turning off....even when it was turning on.......just saying im not sure if what you said is normal according to the sub you own.....but yes sometimes depending on the amp and contruction the amp can make some pop sound when turning on or off........

 

[TLS Guy]

maybe that amp needs just more time to get ''off''...ive experienced that before with the paradigm dsp-3400....and seismic12....when no signal it makes a ''pop'' sound when turning off....even when it was turning on.......just saying im not sure if what you said is normal according to the sub you own.....but yes sometimes depending on the amp and contruction the amp can make some pop sound when turning on or off........

He gets popping every three to five minutes when off!