Field Coil conversion for JBL, Altec, and Western

[fulken]

Over in Japan, I have group of friends who are passionated about field coil drivers. They convert their favorite vintage drivers to field coil magnet circuit. They are the most well known field coil gurus in Japan.

They did conversion for Altec 515B, 802D, and WE 2090A.

Now they are planning to convert JBL LE8T.
If they can find some more people to join this project, they can reduce the cost(and maybe yours as well) . They can also share information or supply conversion kit for Altec 515B, 802D, WE 2090A and 288.


First, You need to prepare LE8T baskets.

Option 1:
They will send you machined magnet circuits and field coil. you needs to assemble them, then You can recone or use your local shop for recone.

Option 2:
After removing diaphragms, Ship your drivers to Japan. They will assemble the field coil magnet circuit, and ship back to you. You can recone or use your local shop for recone.


Yes, I am a full range feild coil guy (Feastrex) but had love affair with VOT in my past


If anyone interested, please let me know! I will help you communicating with them in Japanese

Altec 515B:








Altec 802D:








WE 2090A:

[fabcam]

I may help you, if you did not find other ways.
fabcam@alice.it

[fulken]

Hello fabcam,

so far, I did not get much response for field coil conversion. My friend's latest work is converting Fostex T90A tweeters.

Cheers,
Kenji

Originally Posted by fabcam

I may help you, if you did not find other ways.
fabcam@alice.it

[kevinkr]

Probably would help if it were in the right forum which is the multi-way forum.

Moving to appropriate forum..

I run vintage JBL and Altec hardware, but my suspicion is even if this stuff were available for my specific drivers it is so far outside of my price range that I can't even consider it. I think this is the real problem with these conversions. I've heard RCA theater drivers with field coils and like them, but these are a rich man's game.

[fulken]

Hello Kevinker,

You are right about that! Writing in Feastrex commercial area is kind a "bug" free, and I posted in here...

I enjoy field coil drivers, but my love is in full range now

Cheers,
Kenji

[kevinkr]

I suspect I would probably like your full range drivers, but haven't been thrilled at all with the Fostex FE-165 based stuff I have played with. (To the extent that I more or less gave them away.) My exposure thus far has been pretty limited. Some of the Tang Band stuff like the W8-1772 looks interesting.

The best full range driver I have ever heard is the RCA LC-1 (not sure which version off the top of my head) and again under very limited circumstances.

The things I listen for generally are not well served by FR drivers.

[Inductor]

Yes, expensive... unless used for a lucky guy/girl (for 75 bucks!) RCA Field Coil 15" + Baffle,
RCA Field Coil 15" + Baffle
Incredible fullrange driver, Rullit 12" field coil in massive horns
HQ Speaker | Wolf von Langa
Decware FRX Full Range Driver

[audiofilofine]

230 volt field coil woofer ,driver and tweeter with tube power supply



another photo
audiofilofine field coil speakers

[Pano]

Lovely pictures that hint at the process. What would be nice - since this is a DIY forum - is some instruction on building field coils. At least a photo-essay showing how it's done, along with some guidelines about windings and wire gauge.

[Inductor]

audiofilofine, many kudos.
What was the "Volume Effetti" knob for.
Was that the PA system from an old cinema in Italy (FEDI, Milano, Apparecchi Cinematografici e Radio)?
It took me sometime to see everything. Lovely blog, videos and pictures.