EPI 120B woofer foam

[RTally]

Last year I bought a pair of EPI 120B speakers for little money. When I got them home, I tore into them and discovered that someone had replaced the original 10" woofers with Radio Shack Cat. No. 40-1331B drivers. Bah!

Well I finally found some replacement woofers. The pair of drivers cost me less than one replacement driver from Human Speakers. (I am cheap.) They look to have been refoamed with flat surrounds with the outer flange glued on top of the speaker gasket. I know EPI did that with the 8" butyl surrounds, but I have never encountered it with foam surrounds.

Picture of woofer. Based on comparison to pictures of other woofers and the similarity of the rear label to that I see on other EPI woofers, I believe this is the correct driver for the EPI 120B.


Closeup of foam showing outer flange on top of a thin fiber gasket. The gasket is paper fiber, about 1/16" thick. It is not the remnant of the previous surround.


The foam is supple and does not seem ready to disintegrate. The flat surround is not planar with the basket edge. Instead, the inner flange is a bit lower at the roll than the outer flange.

I am rebuilding the 120B with new caps and rear speaker terminals. I have new foams of the Boston-fillet style that appear to be the proper size. I am going to refoam because that flat foam has a narrow roll (1/2") and the cone shows little excursion, definitely less excursion than the EPI 8" cones.

My question is, when I refoam, should I attach the foam to the steel basket or should it go on the gasket. My guess is that the foam should have been attached directly to the metal basket.

 

[Bill S]

Last year I bought a pair of EPI 120B speakers for little money. When I got them home, I tore into them and discovered that someone had replaced the original 10" woofers with Radio Shack Cat. No. 40-1331B drivers. Bah!

Well I finally found some replacement woofers. The pair of drivers cost me less than one replacement driver from Human Speakers. (I am cheap.) They look to have been refoamed with flat surrounds with the outer flange glued on top of the speaker gasket. I know EPI did that with the 8" butyl surrounds, but I have never encountered it with foam surrounds.

Picture of woofer. Based on comparison to pictures of other woofers and the similarity of the rear label to that I see on other EPI woofers, I believe this is the correct driver for the EPI 120B.
View attachment 2866140 View attachment 2866142

Closeup of foam showing outer flange on top of a thin fiber gasket. The gasket is paper fiber, about 1/16" thick. It is not the remnant of the previous surround.
View attachment 2866141

The foam is supple and does not seem ready to disintegrate. The flat surround is not planar with the basket edge. Instead, the inner flange is a bit lower at the roll than the outer flange.

I am rebuilding the 120B with new caps and rear speaker terminals. I have new foams of the Boston-fillet style that appear to be the proper size. I am going to refoam because that flat foam has a narrow roll (1/2") and the cone shows little excursion, definitely less excursion than the EPI 8" cones.

My question is, when I refoam, should I attach the foam to the steel basket or should it go on the gasket. My guess is that the foam should have been attached directly to the metal basket.

Basket. The gasket material if there was any goes on top of the fillet.

 

[Stuart Pedaso]

When you remove the current surrounds, there might be visible traces of factory foam layered beneath the flange gasket.

 

[vintagerocks]

I have refoamed several sets EPI 120B woofers and the original foam on all was glued on top of the gasket. Your pictures show the correct way the foams should, but they could have done a neater job on trimming the foams. The important thing is how do the woofers sound.

 

[RTally]

I have refoamed several sets EPI 120B woofers and the original foam on all was glued on top of the gasket. Your pictures show the correct way the foams should, but they could have done a neater job on trimming the foams. The important thing is how do the woofers sound.

Thanks for the info. Your pictures show flat-style surrounds, just like on mine. So I assume that the 10" EPI woofer does not use the same style surround as the 8".

I have not yet installed the drivers so I do not know how they sound. I am going to recap and replace the rear speaker terminals this weekend, so I will know soon how they sound.

 

[RTally]

The important thing is how do the woofers sound.

Installed Dayton caps, replaced the crappy spring clips with 5-way binding posts, and installed the replacement woofers from ebay.

They sound pretty good. i am powering them with a Yamaha R-9 at 125 wpc in my office (not a good environment). The 10" woofers let me feel the bass. And they do a better job of filling the space with sound than my not-quite-good-performing Genesis II (that is another topic soon to be posted).

The EPI 120B are destined for my garage system. I will have them next to my OLA. Somehow, I think the EPI will displace the OLA.

 

[Pete B]

Please let us know how they compare to the OLA s, very curious to know.

 

[RTally]

Please let us know how they compare to the OLA s, very curious to know.

I am really liking these EPI 120B. I ran them head-to-head with my OLA in my garage. As you can see from the background, my garage is filled with junk with some room left over for two cars. On weekends I move my car out and workout in the garage and the driveway.

Both the OLA and EPI are fully restored: new metalized poly caps and foam. I have a Yamaha RX-770 driving an Adcom 5300 through Y-connectors. There is a slight SPL difference between the speakers and the amp, probably no more than about 2 dB (less than the increase when running both at the same time). I have a remote for the Yamaha, so a single tap on the volume button is enough to match the volume level when switching between speakers. My source is a ChromeCast Audio connected to a Logitech Media Server (LMS) playing ripped WAV files from CDs.

I positioned the two pairs on the garage floor side-by-side with about 7 feet separation. I connected one pair to the Yamaha and the other pair to the Adcom. I then switched amps between the speakers.



The OLA and EPI are more similar than different. I generally listen to rock (both classic and modern). There was no clear winner at the bottom end. I played some modern R&B and some electronic music with some strong bass lines. The OLA seemed to do very slightly better with the very low bass.

The biggest difference was in the high frequencies. The EPI do a lot better than the OLA at the high end. I have always thought the biggest failing of the old Advents were the fried egg tweeter. The EPI inverted dome tweeter sounded much better than the OLA tweeter.

After testing for an hour or two, I put on Dire Straits Brothers in Arms. Both sets of speakers sounded very good. Half-way through the album I switched to the EPI speakers as I started to do some work around the garage.

I was outside moving into the garage when I heard crickets. Crickets? In the middle of the afternoon on a hot, sunny day? I walked into the garage and the crickets got louder. Duh. I realized I was hearing the crickets at the end of Track 6, Ride Across the River. I switched to the OLA and queued up the cricket/nature sounds at the end of the track. Yep, I hear them. But that sound is much more distinct on the EPI speakers than the OLA.

 

[C Hart]

Glad you finally found the right woofers for those excellent speakers. I auditioned the EPIs against a bunch of similarly priced speakers including OLAs (and KLH, AR, Ohm etc) at TechHifi in Boston. The EPIs were the best of all of them, so they became my first hifi speakers. I even liked that blingey trim.