Actual subwoofer rattling

[writeoff]

My subwoofer has started to make a rattle noise internally I believe, it almost sounds like air escaping, the box it still fully sealed but when it kicks it makes that noise. Does any one have some insight as to what is causing this? I don't really know a whole lot. It is only two months old.

[HCVP]

Well what sub is it,
what type of enclosure is it,
who built the enclosure,
what amp do you have,
have it always done it, or is it only something recent,
does it do it at all volume levels,

[writeoff]

It is an alpine s type 12" I think
Sealed
Built by my dad to exact recommended specs
The amp is an alpine MRX-M50
No, only started roughly mid last week
Yes but at low volume it is difficult to hear the noise, as the volume increases it gets louder but not at the same scale, it increases faster (ie if the volume is linear and the noise is exponential)

[MAG00]

Take the subwoofer out of the box and inspect it. Closely observe for any loose or broken parts.

[writeoff]

I did that this arvo, unfortunately I can't see any of that, not even signs of heat, looks identical to the day I bought it

[wrx884]

re seal the sub box even if it looks ok and see if that does anything.

[MAG00]

I did that this arvo, unfortunately I can't see any of that, not even signs of heat, looks identical to the day I bought it

Play music through the subwoofer while it is outside of the box. You won't damage it. Just keep the volume down, it will be very noticeable if you're pushing it too hard.

[patrick niesler]

I did that this arvo, unfortunately I can't see any of that, not even signs of heat, looks identical to the day I bought it

There was no funny smell to the sub either? Voice coil might be a long shot, you'd probably have known as soon as you pulled it out would have smelt bad but its a possibility if the sub is making a weird noise and not generating a deep tone.

[HCVP]

re seal the sub box even if it looks ok and see if that does anything.

Just a side note if your planning on using silicone let it completely cure before putting the sub back in the enclosure.

[writeoff]

There was no funny smell to the sub either? Voice coil might be a long shot, you'd probably have known as soon as you pulled it out would have smelt bad but its a possibility if the sub is making a weird noise and not generating a deep tone.

Nope, smelled perfectly fine.

@HCVP I will let it set before testing, thanks for the head up. Hadn't planned in silicone but may as well.

[Crisis63]

Once you have checked the box and re sealed it if it still happens it may be the voice coil is stuffed. They can scrape along the inside of the magnet.

[MAG00]

Once you have checked the box and re sealed it if it still happens it may be the voice coil is stuffed. They can scrape along the inside of the magnet.

It could be a number of things, from cone surround coming loose to voice coil rub. Which is exactly why I suggested he runs the subwoofer out of the box, so he can identify where on the subwoofer the noise is coming from.

Take the subwoofer out of the box, run it at a low volume and listen for issues.