A 416 dilemma. What to do?

[bfish]

I'll admit, that I don't have a firm grasp on what a few thousandth is........ although, I suppose I could dig out a feeler gauge. It just doesn't seem like sandpaper in the gap could remove much of anything. Maybe I lack the patience to damage something that slowly

I can say from first hand experience that it's not that hard with emory cloth. I destroyed a driver that way myself once. :doh:

PM me for the detailed technique if you wanna try it...

So, if a bear craps in the woods and there's no one there to hear it, does it still smell...?

[airboss]

I can say from first hand experience that it's not that hard with emory cloth. I destroyed a driver that way myself once. :doh:

PM me for the detailed technique if you wanna try it...

So, if a bear craps in the woods and there's no one there to hear it, does it still smell...?

It's so hard to tell isn't it. I keep thinking about water intrusion. I remember sitting under poncho's at outdoor concerts back in the day, pouring down rain, all smoked up and the A7s out in the open soaking up water.

Somebody mentioned return path problems. The back caps on the magnets are pressure fit with a couple little welds to keep them in place. It looks like the center hole has some sort of threaded connection to something inside. The alnico slug? Both these areas would allow intrusion of water. Are they full of rust? I dunno. We could document this photographically and learn something.

I just wish there was a way to pull the magnet structure without ripping the cone off because I have two identical magnets that I would donate to the investigation. Can the spider be moved and the screw heads be gotten to? I really don't know. Maybe we could drain and recharge mine and stick them on Pano's baskets. I just dunno. My investment, if it was much, was a long time ago and long ago forgotten. And besides OG is pretty sure I'm full of it in the 418B department and it may be the unit I have that still works is in need of a re-mag/cone etc to be representative anyway. In other words, let's rip them up and give it another try. But I would insist on GPA just to keep all things consistent. I'll rip the cones out tonight Pano, and send you the magnets if you want to get to the bottom of it. Just a guess but, I looked at them and I think a guy could get inside for a look and then do a quick mig weld for closure. They were welded shut once, they could be done again.

[Audio_by_Goodwill]

So, if a bear craps in the woods and there's no one there to hear it, does it still smell...?

I think that depends on whether or not it ends up on the bottom of someone shoe later.

[Panomaniac]

Thanks airboss. I do believe that the magnets will not come off without removing the spider - and maybe the cone too. For that I'm going to wait. These may be usable to someone as they are.

If they turn out to be really useless duds then ripping those beautiful new cones off won't hurt so much.

I'm off to Dallas this morning to the Lone Star Audio Fest. Will be pounding the guests with an open baffle rig of Altec 605 and Eminence 18". Gonna be fun!

[Earl K]

I just wish there was a way to pull the magnet structure without ripping the cone off because I have two identical magnets that I would donate to the investigation. Can the spider be moved and the screw heads be gotten to? I really don't know. Maybe we could drain and recharge mine and stick them on Pano's baskets. I just dunno. My investment, if it was much, was a long time ago and long ago forgotten. And besides OG is pretty sure I'm full of it in the 418B department and it may be the unit I have that still works is in need of a re-mag/cone etc to be representative anyway. In other words, let's rip them up and give it another try. But I would insist on GPA just to keep all things consistent. I'll rip the cones out tonight Pano, and send you the magnets if you want to get to the bottom of it. Just a guess but, I looked at them and I think a guy could get inside for a look and then do a quick mig weld for closure. They were welded shut once, they could be done again.

Dan, that's a very generous offer, to give up your 418s for the sake of science .

FYI, ( the scuttlebutt that I've heard is ) once the magnetic circuit is broken ( by removing either the back-plate or the top-plate ) , the alnico slug must be recharged .
I believe it has something to do with a possible field reversal ( leading too a partial demag ) when the plates are pried apart ( & apparently the direction of the plate movement also matters ) .

I can spot chicken shit and envy from mile away though.
This thread, and I'm not talking about everyone, has brought out the lynch mob mentality here and I think it's time for some moderation.

In my neck of the woods we use the phrase "fly shit" to describe the action of "obsessing over a trivial matter" .

I'm not sure if that was the message behind your words that I've quoted but ( fwiw ) I don't believe this is a worthless obsession to find a way to tweak the SOP of a company ( GPA ) when the change will educate the consumer and allow him to avoid fruitless repairs and expense .

I don't see how this ultimately hurts the PR of any company .

I do understand that many companys wish to avoid the dialogue necessary to get there ( identify a problem & rectify it ) . I hope the GPA is one of those companies that embraces a bit of change when that change is beneficial to all parties .

Obviously I'm bummed because I thought that having the woofers reconed and remagnetized would bring them back to spec. That was not the case for mine.

My desire was to learn more about vintage drivers so that maybe I would not get burned with a bad purchase in the future.

Lets not lose sight of the fact that at this juncture this has now cost Pano some real money ( all in a lousy economy where no ones losses are as quickly forgiven ) .

Anyways, the ( following ) suggested changes to GPAs Standard Operating Procedure ( SOP ) are to avoid these situations ( as referenced in Pano's quote ) . These suggestions are now a week old see here !

• The tweak ( to procedure ) would be to have GPA remag first and then check the gauss level in the gap before proceeding with a recone .
• In the event the magnetic assembly won't hold the charge ( I think it's @ 11,000 gauss within the gap ) then the customer is contacted for further direction .
• I haven't completely thought through the consequences of a negative being given by the customer ( after hearing a woofer is a no-go ) / though I speculate that the alnico slug may still have some value to GPA if it's placed into a better return circuit . Anyways, the customer may just decide to cut his loses at that point and leave GPA to do what they will with the reject .
• Anecdotal evidence ( from Bill Hs experience with magging ) indicates this may be a rare occurance . Therefore I can see some customers opting to avoid the extra test / assuming it's made optional .
• This extra step would need to cost more than the $ 15.00 which Brad ( bfish ) has quoted as the present cost ( since the guass check would slow down the repair process ) .
• There is no reason that this added step ( & cost ) can't be made voluntary from the get-go ( initial contact between customer & GPA ). ie ; the customer is asked if he wants the extra step taken to determne if his woofer is a viable candidate for reconing .

BTW Dan, are you going to shoot Todd White a PM to get involved here in this thread ?

<> cheers Earl K

[Earl K]

Hi,

To save everyone a bit of time ( & space within this post ) here is ;

• My first post in questioning GPAs attitude towards Panos non-performing woofers .
  
• My second post questioning GPAs attitude & process , where I first hint that a workable solution is possible .
• My third post where a solution to their SOP is offered .
• My fourth ( and final post ) talking again about that solution .
  

- Nonetheless, there are enough testimonials ( here, within this thread ) that I would now be quite wary of sending my stuff into GPA for refurbishment ( blissfully thinking that all will be well upon the gears' return ) without some new operational guidelines having first been put in place by GPA .

- It's a real drag ( for a few reasons ) to find that one is now in the position of having to impose new SOPs onto any outfit ( like GPA ) // I usually just take my business elsewhere to avoid the hassle .

My "attitude" telegraphs quite easily since I state my reservations ( about GPAs process ) very early in the thread .

So let me clarify some of those words .
- I usually allow companies to fall on their own swords ( so to speak ) because I'm not in their employ as their "process engineer" to fix their problems.
- I do believe in some market forces being allowed to play out .

Since GPA is the only game in town for Altec lovers, I chose ( pretty early in this thread ) a slightly different tact and have offered a solution.

O.T.O.H ;

Chunk 'em and chalk it up... life goes on.

If you want, I'll send coordinates to my Cache of Monumental Failures. There's always room for more.

Is my deductive reasoning shot...? There are plenty of possible reasons, but the drivers are both obviously defective. Maybe the first reconer opened the gap with sandpaper to clear rust or to fit a non-OEM, round wire kit (it happens)... maybe they left the factory bad... maybe they're not 416s at all... maybe... shit happens.

To expect a remag AND full diagnostics for the ~$15 price is ridiculous. We can probably kiss that bargain (for the rest of us with good results) goodbye now.

Brad,

I find your conclusion ( in red ) somewhat callous .

My interpretation of all your posts here ( within this thread ) is that Pano ( or anyone in his position ) has sole ownership of the dilemma that he now finds himself in .

- ie; You seemingly imply that, "even talking about it here threatens the greater good ( such as the possible retirement of the $ 15.00 fee ) / & therefore he ( & the rest of us campaigning for a change to GPAs' process ) should clam up ".

I disagree ( if that is indeed your position ) , my perspective is that everyone here has some culpability when they simply parrot the message that these "old Altec drivers are all fixable over at GPA" . Clearly that message isn't correct and Pano has been misled by it .

I've now offered ( a few times ) my solution on how to avoid having his dilemma repeat itself / therefore I am done with this particular issue . I've had my say .

cheers <> EarlK

PS; ( & FWIW )
- Within the last week I saw a post that something similar to my suggestion was now being implemented at GPA .

[airboss]

Earl, thanks for the correction. Chicken Shit is perhaps too strong a word. But the implied (with a smiley yet) "shut the F up" suggestion by GM is not going down right in anybody's neigborhood. I'm not going to be pushed out for making a very reasonable and polite suggestion.

I first came to this forum back in '03 maybe? I'm not sure. But it was a kinder and gentler place then. Now it seems to have become a hideout for a few self proclaimed experts who's rude comments don't add to the general knowledge. Some people want to tear down, some people want to build up.

I came out of a corporate structure where rank was ignored. I've personally attended roundtables that included the Chief Engineering Vice President of Aleyeska Pipeline Service Company amongst others, where my warnings and advice vis' a vis' work procedures on multi-million dollar valve changouts were treated with as much respect as the contract design engineer. I've come out ahead on most of those discussions primarily because of a penchant for caution when it comes "the rush to judgement"; and a profound understanding of the systems approach to process control. "My well known mantra in Alyeska circles was "Wait a minute, let's think about this for a minute".

Top down management is a no-no at Arco and now BP as it is becoming in most multi-nationals. People with sharp elbows don't last long in this world, and the current crisis in the Gulf (mark my words) will probably boil down to warnings ignored and schedules pushed.

There is no question that I'm not near as well versed in acoustic matters as nearly everyone here. I came for some advice and some of it has been answered with less than civil response. Some folks can't be bothered to mentor the newcomer. They want to belittle him instead. The forum has a collective conscience. It needs to look at itself.

I think you should have a conversation with Bill H yourself. He's available. Finally, if re-magnetizing 60 year old drivers requires a different approach for success, I don't think it should be optional.

[Earl K]

I think you should have a conversation with Bill H yourself. He's available.

I'll do that if Todd doesn't have Bill read my proposal first ( as outlined above ) and then solicit his response for public consumption.

I'll give it till next week some time .

Finally, if re-magnetizing 60 year old drivers requires a different approach for success, I don't think it should be optional.

I need to ponder that some more . Right now I can see pluses & minuses, either way .

<> cheers

[Mustang Marvin]

Airboss,
I feel your pain regarding some of the responses given here. Just because some of us newbees ask redundant or simple questions does not need a response of "That was discussed before, or look at some of the previous threads". Most of the time a simple direct answer can set us straight.

If you look at the number of regular members that post here you will see there are just a few. Why are there not more newbees?. Could it be that they don't want to be told to go and search some buried thread that may or may not answer their questions.

I know most of you that post here are WAY over my head regarding audio knowledge. We all have to learn somewhere and sometime. I am over 60 and sometimes learning doesn't come as easily as it used to.

Thanks to all of those that take the time to help us newbees understand. We do appreciate your effort. I learn more every time I read someones posting. But PLEASE don't beat me up too bad for asking a stupid question. I get that enough from my wife...

[airboss]

I just finished a lengthy conversation via telephone with Bill at GPA. He's going to look in on this thread and maybe make a reply.

#1 Altec alnico speaker magnets structures cannot be drained without complete dissassembly of the magnet structure. Each component of the structure would need to be individually drained. That is very difficult and not necessary.

#2 He does measure flux in the gap before and after re-mag.

#3 I have cancelled my order for a new pair of ferrite 416s at his suggestion because, as he said, you've got to do something with your existing frames right? You're not going to throw them away?

#4 I'll let him explain how driver frames are ruined, but Bfish has part of the answer and the other is dissasembly of the magnet structure by amateur re-coners or just curious "what's in here?" mechanics. There were more, but I can't recall.

There's a bunch of misinformation floating around here, as I thought.

If he's wrong, I'll accept correction only from somebody with a physics background and an engineering degree. Perhaps someone from Thomas and Skinner or MIT. Cal Poly will do.

Enough of the horsefeathers.