Western Electric KS12046

Here's an "audiophile" review of the Line Magnetic field coil 755-look-alike:

Line Magnetic Audio LM 755i field coil speaker Review - Equipment Reviews - Dagogo

From the description of the LM as a laid-back fat sounding speaker it does not correspond at all with my experience of the WE/ALTEC original but Jack Roberts obviously liked it the way it is. The WE/ALTEC 755A is crisp and fast as hell.

WE investment potential aside, it seems like you get more for your $10000 with a pair of these than a pr. of lousy beat-up WE wall cabinets.

Yep - that patent (Patent US2549091 - FREQUENCY - CYCLES PER SECOND - Google Patents) seems to be it. Looking at the patent, it doesn't seem that complicated. I can see why they are only rated at 8 watts. The voice coil is very small, so the Xmax must also be pretty small.

So yesterday after I posted that I had never seen a 755A before, I visited a local high end audio store that I had never been to. Valve amps and high dollar gear everywhere. The owner actually had a couple of 755As that he had been playing with. So I have now held them in my hands, but still haven't actually heard them.

Beautiful woodwork on that Line Magnetics 755. But for $10k, one could get some pretty nice Martin Logans...

I used to sell Martin Logans. I'd take the 755As or the Line Magnetics, personally!

Maybe the MLs have gotten better in the past 20 years but I'm not counting on it.

Everything makes more or less sense on paper. The magic in some of the great classics is how they actually work WAY better than the schematic or plan indicates. There are a few Western Electric items like that and I'd put a few items from the 1947 WE Loudspeaker Catalog in that category.

There are a lot of speakers that are theoretically well designed but in practice are average or worse. some, like most of the good ALTECs, are well-designed and perform to expectations

I know a few other people who, like me, haven't lost our sense of wonder about that 8" speaker. I was hanging out with the top WE guys from Korea and Japan a few months ago and we spent three or four hours talking about 755As and comparing notes. Everybody there has had decades of experience with monster horn systems, pretty much all the fancy pro stuff of the 20th c.--ALTEC, Lansing Mfg. Co., Siemens/Klangfilm, Western. My Japanese friends have been through warehouses of Western gear and literally thousands of 755As. They take 755A apart with microscopes and repair them.

The 755A seemed to be our favorite topic, even while we were listening to the mega rare and fabulous 1927 WE 12A and 13A, so rare that there is not a stereo pair in all of Japan.

I suppose, in the end, we just don't fully understand how the 755A is what it is. It doesn't seem reducible to the blueprint in any clearcut way. It is still surprising and mysterious.

Most of the ALTEC gear that I love, I feel like I understand it. I even feel like I "understand" the Western Electric Full Range and Mirrophonic systems, although the 594A driver/26A horn combo can be shocking at times.

With 755As and 757As, I hear things that no other speakers do and it sure retains my interest and sense of wonder.

Here's a youtube of one such occasion. Drinking beers after hours at CES, listening to James Brown pretty loud. I heard these songs 100X but never on the 757A. It was a totally different presentation from what I knew. Intense!

https://www.youtube.com/watch?v=B3ptEODoQ1A


I don't think everybody would react to this equipment like this but there are some of us out there.

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Originally Posted by Geekstar

I used to sell Martin Logans. I'd take the 755As or the Line Magnetics, personally!

Maybe the MLs have gotten better in the past 20 years but I'm not counting on it.

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M-Ls are one of the few speaker that glue me to the seat. Of course that seat has to be in the 'sweet spot'. :)

It would be fun to actually hear some well-setup old W-E gear. I have no idea whether they still have them, but my audiophile uncle (RIP) and I used to enjoy attending some 'high end audiophile' shows that they had here on the west coast. Don't remember there being any vintage rooms demoing W-E tho.

I note that there is a Line Magnetics dealer up in San Francisco. Perhaps sometime when I am up there, minus the wife and kids, I will stop in and check the modern version out.

Quote:

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Originally Posted by wws944

The voice coil is very small, so the Xmax must also be pretty small.

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Care to explain that? A small coil can have the same Xmax as a larger coil, diameter and Xmax are not related. Though if you are saying 755 Xmax is small, likely correct.

Xmax is influenced by coil length, not diameter.

Quote:

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Originally Posted by Old Guy

Care to explain that? A small coil can have the same Xmax as a larger coil, diameter and Xmax are not related. Though if you are saying 755 Xmax is small, likely correct.

Xmax is influenced by coil length, not diameter.

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Did you check out the drawing in the patent? The length of the VC (#24 in figs 1 and 2) looks pretty small to me. Of course a real production example could be quite different. I admit I have never torn one apart. (Just saw my first one in person two days ago.)

Makes a little more sense but a short voice coil in a long gap can have larger Xmax (underhung) just as a long coil/short gap can (overhung).