CX50 foam or rubber

22 replies
PI
Offline
Pindsen
Bronze
Posted June 11, 2023 at 07:41 GMT
#1642378
Hi,
Replacing surrounds on CX50 (or CX100) you can many places choose between foam or rubber.
Was the CX50 from factory produced with foam surrounds? and would the characteristics of the speaker change notably by repair with rubber surrounds?

Some claim that using rubber surrounds last longer but what about the sound quality?
What you you choose?

/Pindsen

 

Location: Denmark

SO
Offline
sonavor
Bronze
Posted June 11, 2023 at 21:08 GMT
#1657020
Hi,

The originals were foam type surrounds.
How noticeable the difference is will be purely dependent on the listener.

If you are trying to keep things to the original design then stick with foam surrounds.

It would be interesting if you were to do one with foam surrounds and the other with rubber, then see if you can tell a difference.
Those are pretty easy drivers to replace surrounds on so it wouldn't be difficult to try.
Plus, those being small drivers, the surrounds don't cost much.

If you do the test be your and post about it here.

-sonavor
AdamS
Offline
AdamS
Bronze
Posted June 12, 2023 at 13:38 GMT
#1657025
The originals were foam, therefore I'd replace them with foam.

Changing to rubber will alter the parameters of the drivers and make them sound different. Whether this is an improvement or not is purely subjective.
Mark-sf
Offline
Mark-sf
Bronze
Posted June 12, 2023 at 17:00 GMT
#1657035
Specifically changing from foam to rubber will alter the low frequency resonance changing the bass response.
PI
Offline
Pindsen
Bronze
Posted June 12, 2023 at 17:54 GMT
#1657036
I will try to compare and return with my perspective as I have both.

/Pindsen

Location: Denmark

DI
Offline
Dillen
BronzeModeratorFounder
Posted June 12, 2023 at 21:42 GMT
#1657038
Foam, where foam was used originally.
Repalcing with rubber changes the T/S parameters drastically.
If you only had the T/S to compare, you would never suspect it to be the same driver.

Martin
PI
Offline
Pindsen
Bronze
Posted June 13, 2023 at 15:22 GMT
#1657053
What does T/S mean?

/Pindsen

Location: Denmark

GL
Offline
Glitch
Bronze
Posted June 13, 2023 at 15:42 GMT
#1657054
BL
Offline
Blokkenpiloot
Bronze
Posted June 13, 2023 at 19:02 GMT
#1657056
I also liked glueing foam more, as the glue goes into the foam and paper/carton, which made glueing the surrounds more easilly.

With rubber i often had spots i had to glue twice, with foam, always first time!
XS
Offline
xschop
Bronze
Posted February 9, 2024 at 23:08 GMT
Edited February 9, 2024 at 23:18 GMT
#1662338
I changed my CX30's and CX100's to butyl surrounds and doped the cones. It greatly improved the midrange, yet slightly lowered SPL of the lower bass frequencies. Was a win/win running them with a subwoofer.

 





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