A 416 dilemma. What to do?

[gearfreak]

I like the OB (thinking outside) of the box idea.
Simiarly, maybe they'd be useful as passive radiators for someone?

(perhaps requires removal of the magnets... possible?, never uncorked mine to see what was underneath the cover)

[Panomaniac]

Well, I have thought about open baffle. "Rare! Altec Open Baffle Woofers!"
Not the best choice, but hey, I've seen lots of guys run less optimum woofers on OB and love it.

Also thinking about the magnet. Does it come off? Will it go back on straight? You know that bolt you can see thru the hole in the dust cover. Does it hold the magnet on?

Gotta measure them again.
Still thinkin'......

[bfish]

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.

[speakerdave]

. . . . They were pretty beat . . . .

Possibly the problem is somewhere in the "return circuit." That would effect the reading in the gap as much as a problem with the magnet (I would think).

[Panomaniac]

Not to worry bfish, that's pretty much what I've done for the past year. Written them off.
But every now and again I think "maybe."

Dave - return circuit?

[bfish]

Just a tongue in cheek comment on my part, Pano. Analogous to the great satisfaction and closure I felt at a mock ceremonial burning of my ex's wedding veil after the divorce.

A return circuit failure could be a loss of good mechanical contact in the "shell" components, pole-to-plate, plate-to-pipe, and/or pipe-to-plate. The shell is steel, so cracked welds or hidden rust is a possibility. Just as a poor electrical contact adds resistance, poor mechanical contact adds reluctance.

[Panomaniac]

Oh, right. Now I see. Well could be, I suppose. They don't look that bad, but one never knows.

Can they be taken apart? Should I make field coil drivers out of them? Just hate to see any Altec gear go to waste, but it may have to.

[Tom Brennan]

Use them in an open baffle; many people that make OBs like them even though they usually sound bad.

[airboss]

Oh, right. Now I see. Well could be, I suppose. They don't look that bad, but one never knows.

Can they be taken apart? Should I make field coil drivers out of them? Just hate to see any Altec gear go to waste, but it may have to.

Let me qualify what I'm about to say with a disclaimer. I used to take speakers apart all the time when I was a kid just to play with the magnets.

Unless the entire speaker frame is made of alnico, my guess is that those magnets will come apart. They may require riveting or welding to put back together. Not difficult when you want to rescue them. It seems to me though, that to rescue an LTV altec frame by distroying an older one would not make sense UNLESS, the basket on the earlier 416/418/421 had been run over by a buss full o' hippies. I'm surprised that Bill H didn't have some sort of solution, ie refitting with new magnet assemblies.

Otherwise I'm with others that say toss them.

I've got two suitable 15" non LTV baskets and one 417-8C LTV. I've got a very early straight 417(so suffix) that is not ling.

Question: Can recones be taken off and moved to a new home, or is that glue forever?

Another option, have Weber re-cone them into a 15" guitar speaker, with aluminum dust covers. Nobody cares about Qts in an open back cab. Might make a nice Vibroverb.

[Steve Schell]

I'm afraid I am not conversant with TS parameters, so my comments here are general, not specific. AFAIK, the only real way to assess the state of charge of the magnets is to measure the flux density in the voice coil gap directly with a gauss meter. Then the readings, made at several points around the gap, can be compared to the driver spec.

I agree with Earl that the LTV era construction may have paved the way for undersized magnets. The 416 was the smaller magnet woofer to begin with, and these cheapskates had recently given the new, downspeced 804A compression driver a really tiny alnico magnet.