Qe dustcap replacement.

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hey I just picked up a pair of these at goodwill for the princely sum of $25 and they sound pretty darn good. One of the woofer's dustcaps is missing entirely. I just googled dust cap replacement and found there's a school of thought that some speakers sound better without them. So...if you Qe folks were me, would you yard the other dustcap or try to replace the missing one? I'm going to listen closely later to see what if any difference I can tell the cap makes in the sound, but I thought I'd see what you folks who have them think..
 
The dust cap keeps dust (and other small itesm) out of the voice coil. If the designer had wanted it to be free breathing, he would have specified one with an open weave. I'd replace it.
 
The dust cap keeps dust (and other small itesm) out of the voice coil. If the designer had wanted it to be free breathing, he would have specified one with an open weave. I'd replace it.
Reasonable thinking. I’ll get some and give it a whirl, along with replacing the cap in the cap in the crossover. Mine say 9.5 uf which is what the schematic calls for. Wondering if going with 10uf will change the sound at all.. 9.5uf seems like a harder to find value for nice caps.
 
Reasonable thinking. I’ll get some and give it a whirl, along with replacing the cap in the cap in the crossover. Mine say 9.5 uf which is what the schematic calls for. Wondering if going with 10uf will change the sound at all.. 9.5uf seems like a harder to find value for nice caps.
Get the right value as using a 10uF will shift the crossover point (downward) which may be bad for the emit. You can parallel caps with values like an 8uF with a 1.5uF (or any other combination that adds up to 9.5) to get the correct value. Unlike resistors, capacitor values are additive when used in parallel. Hope that helps.
 
make sense. I ordered some 6.2 and 3.3uf Daytons, along with dustcaps from PE. The woofer with the dustcap comes back slowly and the one without springs back immediately which would seem to mean that without the dustcaps the woofer doesn't have some damping that I assume the designer figured into the design. Will be patient and do a proper restore on these.

Thanks
 
The woofer with the dustcap comes back slowly and the one without springs back immediately which would seem to mean that without the dustcaps the woofer doesn't have some damping that I assume the designer figured into the design.

You are right about that, the Qe is an acoustic suspension speaker where the air in the sealed box acts as a spring. Without the dust cap, the box is effectivly unsealed...
 
Well my first dustcap replacement isn’t the prettiest (the adhesive I used doesn’t dry clear..) but the speaker is re-wired and the cap replaced and it sounds good. On to the other one..
 

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