Can a missing dust cap damage a speaker?

[Ricplaya]

Currently looking at some vintage speakers for sale

The seller purchased the speakers missing the dust cap.

Being most speaker designs were acoustic suspension in that era I read that the loss of preassure being the cap is missing could damage the speaker?

Just wanted to verify if there is some truth to that and if I do inspect these speakers what should I be on the lookout for?

Thanks!

 

[Jlord]

No idea about the loss of pressure theory, but I can tell you that if you get debris in the voice coil, then you are going to have problems.

Best if you get new dust caps.

 

[89grand]

I doubt most dust caps could contain air pressure as some are even a mesh sort of material. The biggest reason for them is as the name implies. They are to keep dust and crap out of the voice coil assembly.

Unless the driver had a vented pole piece, air pressure would not even be able to escape through the voice coil.

 

[bowtie427ss]

If it was a solid cap(air tight) and the motor is vented thru the rear, a missing cap will change the cabinet tuning. That could result in over excursion and damage.

........I can tell you that if you get debris in the voice coil, then you are going to have problems.

:yes: We call it "crap in the gap", and it's not something you want.

Unless the driver had a vented pole piece

it doesn't have to be thru the pole piece, there are other means of venting and if the motor is vented in any way behind the cone, the speaker must have a solid dust cap to both vent properly and meet it's parameters in an enclosure.