CSS EL-70 phase plug?

[cjkpkg]

Well I came home from traveling for work and one of my new CSS EL-70's in my fonken floorstanders has a severely dented dust cap...

Would any of the fostex phase plugs out there be a fit?

Worst part is no one fessed up to it

[planet10]

I'll check with Mark on the VC diameter. If it isn't the same as an existing plug, i'd have to get 50 made to do tje job.

dave

[italynstylion]

If I recall correctly, isn't the VC bonded directly to the dustcap in the EL-70's? Would that pose a problem?

[planet10]

The dustcap is bonded directly to the end of the voice-coil. might make it a little trickier to do the dustcapectomy.

dave

[markaudio]

Hi Guys,
The EL-70 uses a 2-pack epoxy bond that's applied to the space between the cap, cone neck and voice coil former. Ummmmph.......I think extracting the cap is going to be difficult. There's more that a good chance of damaging the cone neck.

Might be worth trying by carefully cutting the top off the cap and gradually unpicking the glue, but no guarantees this is going to workout.

Cheers

Mark.

[planet10]

That is similar to how the fostex FE126/127. On these we cut the cap (carefully into 4 quadrants and then just cut it back to the voice coil, leaving the glue & the remainder of the cap in place.

Mark, what is the VC diameter. And are there any gotchas like in the 126/127?

dave

[markaudio]

Ummmmph, cutting and peeling back the cap might work but could still disturb the bond between the cone and VC as the gluing is an all-in-one process for this particular part of the sub-assembly. If this bond is compromised, its pretty much the curtain call for the driver.

Providing the cap isn't punctured, I'd attempt to suck the cap back into shape with a vacuum cleaner with a small nozzle as a first option. I've rescued allot of caps and cones with this method.

Either method maybe worth doing since I guess if the caps so bad, there's little to loose.

VC OD (excluding winding) = 19.7-mm
VC ID = 19.3-mm

Cheers

Mark.

[planet10]

Originally Posted by markaudio

VC ID = 19.3-mm

Thanx Mark,

If i go thru the batch of FE108eS plug blanks and choose the smallest diameter, they should fit. I would recommend getting unfinished ones so that you can adjust the length and, if necessary sand down the barrel (a pain to do but what i do when i need a plug for the holey basket Coral version of the FE103A).

Note, that like the FE126/127 i do not recommend plugs for the EL70 unless it is the only way to recover a damaged dustcap. I've (luckily) not yet had to muck with an EL70 dustcap.

I have never had any luck with the vacuum cleaner, but have done a half decent job with a pin prick to lever out the cap. It doesn't come out perfect thou.

As the dustcap does a significant amount of the HF extension, losing the caps, or the inevitable reduction in stiffness from having creased the cap, the extreme top end will probably not be the same.

One trick passed on by a customer with dented FE126, was to carefully push in the cap (not too much) to create an inverted dome. He preferred them that way (until he tried too much of a good thing and pushed them too far).

dave

[planet10]

Here is the picture i meant to attach in post $6 of some FE127 recovered from dust cap failure.

dave

[cjkpkg]

OK,

I have ordered another EL-70...however I may perform surgery on this one for experimentation...

Thanks for the replies...