Vent hole in sealed subs?

[chris661]

Most paper coned speakers will allow atmospheric pressure equilisation anyway.

Someone on here advised drilling a hole, then putting felt over it.

[Raoul]

Adire Audio had a formula for calculating driver sag. It can still be found in the wayback machine archives: http://web.archive.org/web/200510141...rientation.pdf

Hope this helps.

[killerfishes]

Originally Posted by Raoul

. It can still be found in the wayback machine archives:
Hope this helps.

Good stuff i lost that info long ago along with over 100hrs of engine performance research

[tomchr]

Originally Posted by chris661

Most paper coned speakers will allow atmospheric pressure equilisation anyway.

Someone on here advised drilling a hole, then putting felt over it.

I think the key is that there needs to be enough leaks in the box to allow the pressure to stabilize as the atmospheric pressure changes. Normally this isn't an issue as it is near impossible to make a box completely air tight. But if you're worried about it, drill a tiny hole in the box or leave a minuscule gap in the gasket around the driver. The leak just need to be small enough that it takes many seconds for the pressure to equalize.

That's the take-home message I got out of this...

~Tom

[Cal Weldon]

I respectfully disagree.

The take home message should be that no driver is airtight and that this whole thread is a moot point. You should not consider drilling a hole or leaving any sort of leak in your cabinet, you should strive to make it as airtight as possible. Many other materials such as curved glass window units for solariums do have to deal with this when shipping by air, hence the bleeder tubes. Not speakers.

[tsmith1315]

Atmospheric pressure changes are not large and rapid enough in a fixed locale to outweigh the inherent leak through the driver. If they are, then your local weather concerns are of far greater importance than critical listening.

Unless your speaker is capable of holding a vacuum (it ain't), there will be leakage no matter what pains you go through to seal it.

I consider a closed box well-sealed when the cone feels stiff and takes a second or so to return to center after pressing the cone in. This may require sealing terminals, too.

If it makes you feel better, then drill a hole. I put too much work in my boxes to drill into them unnecessarily.


(edit) sorry Cal, your post wasn't there when I began to reply.

[Cal Weldon]

Actually I should clarify with something I just read. When shipping by air, this may be necessary as it was with one model of BeoLab speakers. I believe it had to do with the quick pressure differential that, as tsmith says, is near impossible on solid ground.