ALNICO Questions

[HDBRbuilder]

Call me stupid, if you want, but just because I know how to build the speakers that were offered from 76-83, and know what the components in them LOOKED like, doesn't mean I know squat about the components' designations or nuances.

My early 1978 Heresys (and it appears that my newly purchased LaScalas) have the tweeters in them with the kinda light gold colored metal covers with the rounded edges over the magnets. Are these what everybody calls the ALNICO tweeters?....or is that a brand?(I was told they were made by Electrovoice when I worked there)...or does ALNICO mean something special like magnet type, etc..?..maybe ALNICO stands for aluminum/nickel/copper or something?

When Klipsch changed over to the tweeters with the square magnets on them (sometime after I got my Heresys in '78, but before I left in '83), one of the engineers there told me that the reason was that "cobalt magnets had gone way up in price due to the federal government's policy towards apartheid in South Africa causing either an extremely high tariff or not allowing the cobalt from there into this country." He also said that "the newer tweeter types worked just fine, but he personally preferred the older ones."

Are my drivers on my midrange horn lens' ALNICO too? They also have rounded-over edges and kinda grey enamel on them. I was told they were made by CETEC when I worked there.

I was also told that the woofers in the speakers were all made by Eminence speaker company in KY.

I appreciate those in the know about this giving me some clarification...thanks.

BTW....It seems that IF cobalt is really involved in this, then, since the fall of the U.S.S.R.(Russia is broke and could use the money), and since apartheid in South Africa is no longer a political issue...and these two countries have the largest reserves of cobalt (that we know of, but they are finding a sh*tload of stuff in China all the time, now)...there SHOULDN'T be a big problem with making cobalt magnets again at a reasonable price...(My degree is B.S.E. Secondary Social Sciences...not math, physics, or engineering so I am not as up on things as most of you are...but I DO pay attention to geo-economics...LOL!)

This message has been edited by HDBRbuilder on 04-24-2002 at 01:38 PM

[WMcD]

I believe the co in alnico is indeed cobalt. Odd that you can make a magnet without iron, but evidently true.

The newer ones are some sort of ferite (iron) which is formed from a slurry and baked, or something. Hence they are called "mud" magnets.

Gil

[Ray Garrison]

HDBRbuilder:

Try this:

http://www.meta-gizmo.com/Tri/aroma.html

but be prepared for a rather, er, unusual perspective on life, the universe and everything...

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Music is art

Audio is engineering

Ray's Music System

[KGeist]

If I'm not mistaken, I believe one of the problems with Alnico was that it is prone to demagnification.

Kerry

[HDBRbuilder]

ok....good reading so far folks....but is what I have ALNICO or not?....and is it preferred over the other...why or why not?

[Chris Robinson]

Based on your description, your tweeter is definitely alnico. Not sure on the others.

[TBrennan]

Builder---I'll give you some facts and some opinion. Alnico is an alloy containing aluminum, nickel and cobalt. It was first used as a material in permanent magnet speakers by Altec around 1945 after John Hilliard, a big honcho at Altec, became familiar with it while designing magnetic detection anti-submarine devices during The War. Diring the late 1970s many Belgian and French mining engineers and their families were massacred during a rebellion in Zaire, at that time the leading source of cobalt. The Europeans got out of Dodge and cobalt production plummeted and prices skyrocketed. JBL, Altec and EV were forced to redesign their drivers around ferrite magnets (at this time Altec and EV were adding a surcharge to their driver prices to cover the cost of Alnico). JBL and Altec had problems at first getting ferrite woofers to meet their picky standards, problems with symetrical drive caused by the doughnut shape of the ferrite magnets. But these problems were worked out. Ferrite turned out to be an excellent material for compression drivers and the new ferrites had no problems, indeed Altec's first ferrite 1" driver, the 902, is thought by many to be the finest driver they ever made and some prefer the ferrite 515G woofer to the Alnico 515B. TAD stuck with Alnico and this is reflected in their outrageous prices. Any alleged performence advantages of TAD to Altec and JBL are no doubt more due to their use of berilium as a diaphragm material than to what the magnets are made of. So I doubt that the big makers are keen to go back to Alnico seeing as they're getting just as good performence from ferrite. And they're more reliable than Alnicos too, overheating voicecoils and hard knocks will lower the strength of Alnico magnets. Neodynium magnets are happening though, they allow a driver much lighter in weight, important in pro-sound. TAD, JBL and Radian offer some neodynium magnet compression drivers and I think we'll see more of that. I own and have owned many Altec and JBL drivers, both ferrite and Alnico, and I hear no performence difference I can attribute to magnet material. There is an Alnico cult out there, there is a strain in American life that worships the archaic. I don't hold with this particular cult though.

[John Warren]

I agree with what you say except for the overheating part. Alnico magnets are superior to ceramic in elevated temperature conditions. Alnico 5 is difficult to demagnetize by high temperature exposure.

Curie temp of Alnico 5 = 850°C

Curie temp of Ferrite = 450°C

For Alnico 5 up to about 1,000 F, changes in magnetization are largely reversible and re-magnetizable, while changes above this are largely structural and not fully reversible or re-magnetizable. Approximately 90% of room temperature magnetization is retained at temperatures of up to 1,000 F.

For ferrite up to about 840F, changes in magnetization are largely reversible, while changes between 840F and 1800 F are re-magnetizable. For all Ferrite magnets, the degradation of magnetic properties is essentially linear with temperature. At 350 F, about 75% of room temperature magnetization is retained, and at 550 F, about 50% is retained.

This message has been edited by John Warren on 04-24-2002 at 07:02 PM

[TBrennan]

John---Hmmm, maybe I'm being conned by the Alnico remagnetizers. Thanks for the info.

[HDBRbuilder]

Thanks guys, very enlightening...and most important of all, I CAN UNDERSTAND IT!!! It is nice to get technical answers put in a way where I can understand them!

I would love to see more about this issue over driver construction and materials, PROVIDED it doesn't become a heated debate, but is done in an informal manner among friends as I have seen here so far.

Any other comments on the ALNICO vs. ferrite magnets?

By the way, TB, although I like old things, I do not consider myself a worshipper of the archaic...whenever something PROVES it is all-around better at doing something than that which preceded it...I am all for it!!! But, as a woodwooker with many years experience and an affinity for good quality wood, lumber-cored veneered panels and high quality plywoods....just to let you know how I feel about MDF...let me say what my daddy used to say: "Particleboard ain't much better than dogsh*t and tater peelings...you will see that once it gets wet!!!" And that still holds true!!!

[TBrennan]

Builder---I like old things too, Hell, I'M an old thing. And those old Alnico JBL and Altec drivers are beautiful devices, true American industrial art. They had internal slug magnets and the large iron magnetic return structure formed the body which would be nicely finished. An old JBL Alnico compression driver with it's black stove-crackle enamel finish is gorgeous. And so are the old Hammertone green Altecs. And some of the EVs were chromed (well EV WAS in Michigan, obvious Detroit influence). I have a pair of JBL LE-175 drivers sittin' on my coffee table where I can just look at them. :-)

This message has been edited by TBrennan on 04-24-2002 at 10:04 PM

[WMcD]

HDBR, you don't know us very well. Naturally you're one of now.

Heated, but good natured debates are common. Besides some have commented that things are getting too calm.

We need something other than wire to talk about.

BTW, do you know anything about wire? We'll duck our heads. Smile.

Gil

[HDBRbuilder]

Gil,

wire?..You have the nerve to ask if I know about WIRE? Hell, man, I was raised up in Arkansaw...we all know about wire HERE!!!!! Geez!!...nobody EVER leaves the house here without WIRE...and an oilcan...hell, you can fix anything on the old studebaker pickup with that and a pair of old pliers!!!!

But, me not being one to "worship the archaic"....I have been adapting well to duct tape, WD-40, and vise-grips!!!!

[djk]

"Are my drivers on my midrange horn lens' ALNICO too? They also have rounded-over edges and kinda grey enamel on them. I was told they were made by CETEC when I worked there." The alnico K55V was made by Atlas.The CETEC (Gauss) HF 4000 was the mid driver in the early MCM1900, later ones went to four Atlas drivers on a manifold.Remanence of Alnico at high temperature is not the issue, coercivity with four-layer voice coils and high power amplifiers was the main issue in woofers.Compression driver problems were mainly from being dropped and rust.

[HDBRbuilder]

DJK,

As per the squawker drivers on the early MCM1900 being made by CETEC, that makes sense to me, since the little "woofers" that drove its subsquawker were also made by CETEC...If I remember correctly they were something like 8" ones....

Yeah, I also remember the engineers runnin back and forth over to the workbench behind me tryin to make sure those 4-driver throats would fit in the cabinet for the squawker once the drivers were mounted to em...they also toyed with 3-driver throats some...took awhile to figure that little problem out...LOL! The 4-driver throat took what appeared to be the same drivers that were on the heritage series, but the original SINGLE-driver-powered squawker had a driver that was bigger...I guess that is where my confusion came in over who made the squawker drivers for the heritage line...Actually I think both driver types were sitting on the workbench when I asked Jim H. who made them.

BTW....the MWM woofer section sat outside for a very long time...maybe even a year...with white noise runnin through it...in testing...pretty much 24/7. I always thought to myself..."Man, Jim H. would be really ticked-off if he came to work one morning and it was gone!!!"...LOL!

The same tweeters as on the rest of the heritage line were used in the early MCM1900 tweeter box...or at least they looked the same...six of em stack-mounted, with lenses horizontal, in each box....upward/downward dispersion regulated by an by an arced panel secured inside each side of the boxes...to mount the lens flanges to...having the lower tweeter firing upwards the most and the upper tweeter firing downwards the most....the tweeters firing across each others' paths to achieve the dispersion along the vertical axis....the easiest cabinet in that system to build, by the way...LOL! I think the reason they "cross-fired" each other instead of the other way around in the cabinet design was because the arc required didn't allow clearance of the magnets if they reversed it so that the tweeters wouldn't fire across each others paths...and something about the controlled dispersion wouldn't be as good because there would be some gaps the other way...something to do with the lens' flanges' width...the farther out the listener was....who knows?...I just built the cabinets and enjoyed listening to them...LOL!

Another interesting aside about the MCM1900 system: When the first "Star Wars" movie came out, the company had arranged to have a private screening of it for the employees on the Saturday before it opened in Texarkana. Well, we worked overtime that Saturday morning, and at quitting time we all ran home cleaned up, grabbed up the "significant other", and carpooled or rode on the provided buses to Texarkana to watch the movie. We were allowed to bring "refreshments of our own choice" to the theater, but the ice chests had to be brought in through the side exit doors instead of the front door for obvious reasons. The powers that be had hauled a pair of MCM1900's and some heresy monitors and such over to the theater and set them up inside it just for this showing...WOW!!!...WHAT A MOVIE!!!!!!...sure was nice to be sittin there havin a beer with my popcorn watching that and listening to the effects thru something I had built a few weeks before!!!!

[HornEd]

HDBRbuilder, yet another great anecdote from Hope's best known industry by its best "known to the Forum" cabinet banger!

The sad thing is that too few Klipsch folks are getting a chance to enjoy it. I am a retired publisher but I would consider putting out a paper back book including your cabinet tips and anecdotes and gamble on selling enough to break even.

Reading the excellent book on PWK brought to mind how much of the Klipsch Heritage as a speaker company have fallen through the cracks of fading memories. I still have the equipment to put the book to gather and the contacts to have it printed and bound very economically.

Clearly, this forum has been an "eye-opener" as to how much Klipsch nostalgia and audio expertise is represented by the people who post and learn here. The biggest problem is that too few people read a post before it gets pushed down the line into "post oblivion"... and then the same questions already asked and answered come up for a new whirl... as too many people would rather start again than use the easy Forum search facilities.

In any event, I think I would like a "Klipsch Horn Book" as told from the consumer/collector and former employee perspective. Any thoughts? -HornED

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Photo update soon! -HornEd

[edwardre]

Put me down for a copy....

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Ed

[HDBRbuilder]

HornED...

Thanks, I am glad some folks enjoy a bit of my recollections on here. By no means am I an expert on woodworking, nor anything else for that matter...but I feel that I have had a decent amount of experience in that endeavor and am happy to provide some hints and such to those who feel they may be of some use.

As for you suggestion of a book that includes some of this kind of thing and some of the anecdotes...I think it would be a good idea..BUT it should not rest solely on anecdotes from just this humble man's recollections. Besides, if I had thought of my little additions to this forum ending up in a book, I would have put more into the writing of them, instead of just typing it out and firing it off in standard onlne lingo...LOL! I do happen to have laying around somewhere some pics of individuals taken at the plant from that era...and participating in some of the "unofficial" recreational events that were impromptuly organized...if you know what I mean.

As for those of you who would like to read some of my observations on important personalities at Klipsch with whom I have been acquainted, I will post another thread today in this section pertaining to one of them...for your "reading enjoyment." I just hope he doesn't feel a need to hire a "hit-man" to call upon me during the wee hours in the future over this.

"Coming Soon to a Forum Near You: The (mis)Adventures of Engineer Jim"

[JohnA]

I've met Hunter, I've got to hear that!

John

This message has been edited by John Albright on 04-25-2002 at 09:18 PM

[djk]

"As per the squawker drivers on the early MCM1900 being made by CETEC, that makes sense to me, since the little "woofers" that drove its subsquawker were also made by CETEC...If I remember correctly they were something like 8" ones...." Yeah, it was a 10" CETEC (Gauss) driver on the subsquawker "The same tweeters as on the rest of the heritage line were used in the early MCM1900 tweeter box...or at least they looked the same...six of em stack-mounted, with lenses horizontal, in each box...." The original tweeter for the MCM 1900 used five in a vertical concave array.By curving the line source it reduced comb filtering, acting like a point source beyond the focus point.The drivers used were the Motorola KSN1016A.This was a wide dispersion rig. Later they offered a narrow dispersion rig that had two K77M (EV T35) motor strucures on a manifold. All the MCM1900 I have seen had the vertical five tweeter array. I bought a case of 100 of the KSN1016A and made several three to five tweeter arrays. With a proper crossover these sound much better than the K77, although they won't handle as much power.