A 416 dilemma. What to do?

[Earl K]

I have a pair of JBL d130f that, like Pano’s 416s, are sitting unused because they sound like #$%^. Mine also have the higher than spec Qes values. I wonder if a remag would create any sonic miracles !

- Recharging the magnets might help your woofs ( its a long shot ). The too high Fs is pretty worrying . What are the BL and Mms figures for that pair ?

- It's just as likely that both your d130f woofs are reconed with aftermarket parts ( typically Waldom ) and suffer compromised performance as a result . Remagging doesn't help when a speaker has compromised kits in place .
- Look for MW - ###### stamped on the cone to identify Waldom cone-kits .

- IMO, people selling woofers on eBay with aftermarket kits in them ( & not identifying this fact within the sales text ) is tantamount to fraud .

<> cheers

[Panomaniac]

Well as you can imagine, I've become rather shy about this whole remag thing. "Once bitten, twice shy". So how about twice bitten?

Perhaps I was naive going into this, but (almost) everything I'd heard or read up to that point had told me that a recone and remag would make the drivers good as new. I did start out with frames in nice shape, just the cones were not right. Or so I thought.

At this point, I'd want to see real proof that the remag process actually works before I'd drop more money on it. Anyone got before and after measurements that show a significant change?

Color me skeptical.

[sba2]

Thanks Earl

From a yard sale purchase of a pair of Altec 1203, I ended up with some troublesome 807s and these d130fs (which I discovered after getting the 1203s home and removing their backs). Luckily, I didn’t pay too much, but I’ve spent a lot of time chasing problems.

One of the cones is original and slightly abused, the other is a Waldom aftermarket cone.

I think that I’ll have to write these off. On eBay there’s a recone kit for $150. There’s also a recone service for $175 + shipping. And a remag would need to be done by yet another service $15-30 ? (@ GPA) + shipping. It could easily run $250 per driver, with no guarantees. I just saw that PE offers a speaker reconing service…from their online calculator...$125 + shipping. (I doubt that they can remag, so that would be extra). So again, at least $200+ per driver. And all of the above use aftermarket cones.

It may be better to order a new JBL 2226 for $330 at PE with free shipping and a six-week return policy [ Or try the B&C 15” ].

[robertbartsch]

I would not use aftermarket recones or diaphagms for Altec or JBLs for obvious reasons. Yes, I consider the GPA recones and diaphragms = OEM. There are fewer and fewer JBL recone kits availible now, so this is not even an option anymore for many of the JBL vintage line.

Just for kicks, what does a new 416 woofer from GPA cost? How about a 902 HF driver?

My functional currency is USD.

Thx....

[DaveCan]

Just for kicks, what does a new 416 woofer from GPA cost? How about a 902 HF driver?

My functional currency is USD.

Thx....

416-8c = $240 USD each
902-8a = $202 USD each

[Mustang Marvin]

I was under the impression that some of the altec woofs need to be remaged from time to time, but some do not. Maybe Alnico vs. ferrite. can anyone clarify?

Also, I just bought 2 new 399's from GPA for $340 each plus shipping.
I got a quote of $360 for new 416B's also plus shipping.

[Earl K]

I was under the impression that some of the altec woofs need to be remaged from time to time, but some do not. Maybe Alnico vs. ferrite. can anyone clarify?

That's the prevailing wisdom ( that all Alnico magnets will benefit from a recharge ).
ie ; Not just Altec woofers, but any transducer using an Alnico magnet can benefit from a recharge .

Unfortunately, ( & apparently ), the stated wisdom doesn't always hold true / which is the genesis behind this thread . It appears the "charge" won't always take ( hold ) .

If you haven't read the complete thread , then I'd suggest that you do it sooner than later .

As a corollary, member "robertbartsch" had a JBL tweeter ( with an alnico magnet ) rendered unusable ( apparently ) by subjecting it to the remagging process. That's another unsolved GPA remag mystery .

Ferrite magnets rarely demag .

<> cheers

[robertbartsch]

Earl:
I never said the JBL tweeters were deemed useless by GPA in a re-mag job. The 2402 re-charge was done without the noses attached. What happened was (1) the mags/cores were discharged, (2) the mags shifted within the cores since the nose cone and nose cone bolt were not in place, (3) the mags/cores were recharged but the mags were out of alignment.

When I got them back, I could not swap in the new frames and install the horns and noses because the mags were not in the right place.

I shipped them back and Bill and they demaged the cores, re-aligned the mags, recharged the mags, and installed the frames and noses.

In all fairness, it seems a tad weird that Bill would re-mag the 416 cores and not check the mag strength before installing the new VC, cones, etc.

I'm I missing anything obvious?

[Earl K]

Thanks ! for the clarification Robert . I did use the word "apparently" for a reason .

A detailed response ( like you have given above ) to my question ( back in post 26 ) would have had me paraphrase your experience differently .


cheers ><

[robertbartsch]

Is magnet strength testing after a recharge but before a re-cone a standard practice?

Thx...