4333A Project

Hipocrates

Hipocrates

AK Subscriber
Subscriber
Greetings.

A pair 4433A arrived today, I think they are nice projects to have.
So maybe some would like to share some insight regarding this buggers.
I test them on a crappy stereo on the guy who was selling them, tomorrow I will perform more testing
The goal here is to perform a proper reconditioning aesthetically and functional.

To be adressed

./ One muppet "fix" one 2231 woofer removing the surround and gluing the diaphragm.
./ Hideous dust caps.
./ One horn do not produce sound.
./ The walnut veneer needs work.

My plan of action is this:

./ Refresh the crossover
./ Refoam the woofers and install dust cap.
./ Re-wire (i have miles of nice wire around)
./ Remove old and nasty dampening material for new one.
./ fix corners and veneer o maybe re-veneer.
./ Refresh horns. (maybe new diaphragms)
./ Install SVS subwoofers feet (love those ones)

As always any advice about what parts to use, sources and opinion will be highly appreciated.

Cheers!

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Looks like you might've two different woofers. Have you taken them out to look?
 
baco99 said:
Looks like you might've two different woofers. Have you taken them out to look?
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Yupe, last night I took them out.
2231A confirmed.
The problem was that a muppet replace one cone surround and the other just glue the cone to the frame.
 
Hipocrates said:
Yupe, last night I took them out.
2231A confirmed.
The problem was that a muppet replace one cone surround and the other just glue the cone to the frame.
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Looks like one has a pleated surround and one has foam. It's possible that the previous owner replaced one of the cones completely with the wrong kind. The 2225 cone kit fits that speaker assembly and has a pleated surround.
 
Strange.
I would foam them both so they are at least the same. The cone says 2231, so not sure what happened. Maybe one of the pleated surrounds got a tear and the PO just replaced with whatever they could find.
 
baco99 said:
Strange.
I would foam them both so they are at least the same. The cone says 2231, so not sure what happened. Maybe one of the pleated surrounds got a tear and the PO just replaced with whatever they could find.
Click to expand...
And installed the nasty (and gone dust cap)... don't sub estimate a costarrican muppet, they are quite determinate, you should see what the do on vintage receivers.
Refoam it is!
 
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Fun! Me, I would recone the woofers as 2235Hs (JBL cone kits are still available), replace the horn diaphragms with new ones from Radian, and if you need new 2405 diaphragms, you can get those, too. I believe Simply Speakers has the the 2235H recone kits and 2405 diaphragms, and they will special-order the Radians. Omit the 2235 mass rings if you're running a sub or three.

For damping that is just like JBL's, I used "1" yellow bulk insulation" (cat # 16550) at https://wrap-on.com/product/bulk-roll-fiberglass/. Email them and they'll refer you to a seller. Ace Hardware carries it too, I think.
 
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Zonker92 said:
Fun! Me, I would recone the woofers as 2235Hs (JBL cone kits are still available), replace the horn diaphragms with new ones from Radian, and if you need new 2105 diaphragms, you can get those, too. I believe Simply Speakers has the the 2235H recone kits and 2105 diaphragms, and they will special-order the Radians. Omit the 2235 mass rings if you're running a sub or three.

For damping that is just like JBL's, I used "1" yellow bulk insulation" (cat # 16550) at https://wrap-on.com/products/pi.html. Email them and they'll refer you to a seller. Ace Hardware carries it too, I think.
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Thanks for the advice!
I made an order for the refoam kit, and I think I'll keep the recone kit or maybe as a upgrade for later.
I'm pretty sure I can get the yellow insulation locally, seems just fiberglass isn't?

I'm curious that you mention 2105 because this ones use 2420 and 2405.
 
Cool! 2405, I meant (I'll edit above), not 2105; I'm just bad with numbers. I like that fiberglass just because it's the same thickness as the stock stuff.

2420s are nice because they probably already have AL diaphragms, like the Radians. (Although the AL surrounds are brittle and may eventually fatigue and crack, which is why the Radians use Mylar instead.) You might want to remove the back caps (careful with the screws / wires and the magnets), replace the damping foam and inspect the 'phragms.
 
Zonker92 said:
Cool! 2405, I meant (I'll edit above), not 2105; I'm just bad with numbers. I like that fiberglass just because it's the same thickness as the stock stuff.

2420s are nice because they probably already have AL diaphragms, like the Radians. (Although the AL surrounds are brittle and may eventually fatigue and crack, which is why the Radians use Mylar instead.) You might want to remove the back caps (careful with the screws / wires and the magnets), replace the damping foam and inspect the 'phragms.
Click to expand...
Cool, thanks man!
I'll check for the Radian 2420.:naughty:
EDIT:

https://www.parts-express.com/radian-1225-16-diaphragm-fits-most-jbl-1-16-ohm--294-722
Way more inexpensive than the genuines.
https://www.parts-express.com/jbl-d16r2421-genuine-diaphragm-for-2420-2421-16-ohm--294-4010
 
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Nice. I wonder if that JBL part is aluminum, like the original, or titanium, like later models.

It's kind of awesome to call Radian, which reportedly employs some former JBL and/or Altec engineers. It's one of the last domestic audio manufacturers, and when I called they transferred me to the engineer in charge of making these diaphragms, who sounded like he was out walking the factory floor during our call. Super-friendly, knowledgeable and enthusiastic, he spent a good ten minutes telling me about this product, and definitely made me a believer. I really like them in my 4435s, as I did in my 4430s.
 
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Zonker92 said:
Fun! Me, I would recone the woofers as 2235Hs (JBL cone kits are still available), replace the horn diaphragms with new ones from Radian, and if you need new 2405 diaphragms, you can get those, too. I believe Simply Speakers has the the 2235H recone kits and 2405 diaphragms, and they will special-order the Radians. Omit the 2235 mass rings if you're running a sub or three.

For damping that is just like JBL's, I used "1" yellow bulk insulation" (cat # 16550) at https://wrap-on.com/products/pi.html. Email them and they'll refer you to a seller. Ace Hardware carries it too, I think.
Click to expand...


Yeah, that looks like the right stuff. I just don't need 100 square feet of it to do two cabinets. Ace lists the "pink" stuff. :dunno:
 
Some news fellows. I tested the pesky 2420's with a DMM.
2420 horn A: 5.6 MΩ
2420 horn B: 6.1Ω

:smoke:

Horn A was the one with no sound originally, As is my first time working with horns, well to me looks like is fried, which means that diaphragm replacements are mandatory. Correct?
I anything else to test there? Maybe rust...

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Those are original 2420 tangential diaphragms and to the right party, correctly working models are worth more than the cost of new diaphragms. Make sure the connections are clean. Much of what you see at the connections is the old foam that lined the cover.

The tangential diaphragms have a fuller bottom end and are more relaxed at the top end than the subsequent models (2421, 2425).
 
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toddalin said:
Those are original 2420 tangential diaphragms and to the right party, correctly working models are worth more than the cost of new diaphragms. Make sure the connections are clean. Much of what you see at the connections is the old foam that lined the cover.

The tangential diaphragms have a fuller bottom end and are more relaxed at the top end than the subsequent models (2421, 2425).
Click to expand...
Good to know... thanks
 
Now this is what I have in mind regarding this 2420.

./ Clean that rusty crap
./ Replace cables, terminals and screws.
./ Check for good connection on the diaphragm.

Is that ok or I'm missing something?

EDIT.
This little spider the will be deft when I play "Fanfare for the common man" testing this.

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