What is the general consensus on repairing these? foam or rubber.
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Penta 3s foam or rubber? midrange
10 replies
I don't think that there is a consensus. The purists will say foam, since it has the best chance at delivering the same as stock performance. The rest will say rubber, presumably because they think it will last longer(?).
I'm firmly in the foam camp. My assumption is that modern foam formulations won't have the degradation issues that the original ones did. Regardless of longevity, I'd rather listen to (possibly) higher performance than always be wondering what I gave up with the heavier rubber surrounds. YMMV.
Glitch
Compare the T/S parameters of a driver restored with foam to one restored with rubber (both played in to losen up the stiff new surrounds), and you will no longer
have any doubts.
I did exactly that.
I was expecting a difference but... oh dear, was I surprised.
Foam!
Martin
Thank You gents, foam it is then, any particular supplier although i did see one on the bay (not the Chinese one) or the Dutch one AF, will replace the sealing rings as well then perhaps the caps in the crossovers.
Sorry, I didn't keep the numbers.
It was several years ago, but it should be easy to replicate for someone with time and means.
Martin
I have a set of pentas to refoam yet, but likely wont be until mid-24 until I get around to it. I will definitely be using foam surrounds on them and will toss one on the Klippel machine here to measure purely out of curiosity. If anyone has a rubber-surrounded mid they've made, I would be happy to measure it then return it.Location: San Francisco
I'm an automotive audio and acoustic engineer. I design loudspeakers and full sound systems for new automobiles. I also dabble with studio, consumer and pro audio projects from time to time.Hi Group, Got round to refoaming these with foam from AF in the Netherlands, all were a perfect fit but used my own modelling brush for the glue as the one supplied was a bit on the large size, also took Steve from Sounds Heavenly advice and turned one panel so the tweeters were on the inside and must say with the both jobs done the sound is a vast improvement, crossovers next i think. Thank You all for your advice.
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