EPI-100v high quality speaker surrounds that last a long time

[bob412]

I have 2 pairs of EPI-100 speakers that was the recipient of refoam kits five years ago . I was going to sell one pair to a potential buyer online . Upon inspecting this particular pair for sale I decided to test the seal of the speaker . What I found was both speaker foam surrounds had become crumbly . Even the speaker not for sale had crumbly surrounds . Looking at the foam surrounds they looked to be in excellent condition until this little test . The company I purchased them from said the foam will last 10-20 years ,BULL SHIRT ! Anyway I can't sell those until they've been refoamed . Some of these companies will tell you anything just to make sales . I live in deep south east Louisiana and it's quite humid around here . I hear that it's not good for foam based speaker surrounds but my other speakers with foam haven't deteriorated yet . I'm thinking the company I purchased these from got a bad batch of something , wont be purchasing from them again . I want to get away from foam and use butyl rubber for these speakers . Anyone know of a good source of butyl rubber surrounds that will fit EPI-100v speakers with the square magnets ?

 

[swechsler]

Nope. They're foam for a reason. Rubber has a higher mass than foam and will change the woofer's characteristics (which is especially important due to the way the woofer and tweeter work together). Older EPIs used rubber surround, but that was a different woofer; it's not like they kept everything except the surround.

I'd just find a better supplier of the correct foam and go for it. The fact that your other foam surrounded speakers haven't deteriorated is a pretty good indication that the problem was those foams, not foam in general.

 

[bob412]

Nope. They're foam for a reason. Rubber has a higher mass than foam and will change the woofer's characteristics (which is especially important due to the way the woofer and tweeter work together). Older EPIs used rubber surround, but that was a different woofer; it's not like they kept everything except the surround.

I'd just find a better supplier of the correct foam and go for it. The fact that your other foam surrounded speakers haven't deteriorated is a pretty good indication that the problem was those foams, not foam in general.

Thanks for the response . I might as well stick with the foam surrounds since finding this bit of info out .

 

[GordonW]

Actually, it was basically the same woofer- just with the newer, better foam surround. As far as sound goes, it WAS better with the foam.

The early EPI speakers have a quite easily measurable "hole" in the response- a depression in the 1khz to 2.5KHz region, of a couple db, if you look at the response curves at various angles, and average out the frequency response. There's also a phase error there, due to the excessive mass causing a premature rolloff, which degraded the timing of the speaker too.

The later ones- with foam surrounds- were better balanced through the crossover region- which made for a "faster" more dynamic sound. In my experience, they also image somewhat better, too. I know my personal EPI M150s certainly did sound better...

Also- I don't know what made your speaker foam deteriorate so fast. I refoamed mine over a decade ago- and they're still fine...

In fact, I also use foam-surround EPI 8 woofers, as the bass drivers in the doors of my car, since about 2005. In a CAR, where they experience massive humidity shift, and temperature shift between 10 degrees and 130 plus degrees F. They also have lasted for a decade or more. The only reason I ever had to change one of those, was when water got into the door, and into the voice coil- damaging the coil and cone, to where it barely started to make a rubbing sound on heavy bass. But, even so- the surrounds were still fine, even when that happened...

Regards,,
Gordon.

 

[swechsler]

Actually, it was basically the same woofer- just with the newer, better foam surround. As far as sound goes, it WAS better with the foam.

Well, color me surprised. Thanks for the correction.

 

[bob412]

Actually, it was basically the same woofer- just with the newer, better foam surround. As far as sound goes, it WAS better with the foam.

The early EPI speakers have a quite easily measurable "hole" in the response- a depression in the 1khz to 2.5KHz region, of a couple db, if you look at the response curves at various angles, and average out the frequency response. There's also a phase error there, due to the excessive mass causing a premature rolloff, which degraded the timing of the speaker too.

The later ones- with foam surrounds- were better balanced through the crossover region- which made for a "faster" more dynamic sound. In my experience, they also image somewhat better, too. I know my personal EPI M150s certainly did sound better...

Also- I don't know what made your speaker foam deteriorate so fast. I refoamed mine over a decade ago- and they're still fine...

In fact, I also use foam-surround EPI 8 woofers, as the bass drivers in the doors of my car, since about 2005. In a CAR, where they experience massive humidity shift, and temperature shift between 10 degrees and 130 plus degrees F. They also have lasted for a decade or more. The only reason I ever had to change one of those, was when water got into the door, and into the voice coil- damaging the coil and cone, to where it barely started to make a rubbing sound on heavy bass. But, even so- the surrounds were still fine, even when that happened...

Regards,,
Gordon.

Do you remember the name of the company you purchased your EPI-100 foam surround kits from ?

 

[GordonW]

Do you remember the name of the company you purchased your EPI-100 foam surround kits from ?

They came from MWA Speaker Parts. That's a wholesale supplier that sells to most reconing shops in the USA.

The surrounds are the same, as used on Boston Acoustics, EV and a few others. "filletted" (filled) inner edge.

If you buy from a company that does a lot of reconing business- chances are, their surrounds will be "fresh" (not sitting on a shelf for years). That will, obviously, statistically give longer life, after purchase. It's when people start buying surplus or over-stock surrounds, that trouble can arise- those surrounds may have been sitting for years, in who knows what environment...

Regards,
Gordon.