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mesudman
08-21-2010, 12:16 AM
Hello everybody,
Few months ago I bought a pair of 4333A in pretty bad shape. The good thing is I paid 130 bucs for them. The cabinets have water damage and the woofers membrane are not looking good either. I will try to find a good looking pair of PR15 passive woofers and try to replace the membranes.
On the back side they have 4 wire connections, the top ones are missing. I tested them and they work just fine ..for now.They have tousands of hours played in nation television post since the 70' and hope I won't be forced to change the diaphrams of the drivers.
After I saw spirou38 , richluvsound and hofmannhp posts (thank you guys!!!) I decided to restore them.
Here are some pictures of them.

mesudman
08-21-2010, 01:12 AM
I removed the black paint with a heated gun and after with a speacial machine I refubished and leveled the surfaces of the cabinets.
I ordered walnut veneer and in the meantime I prepared the front surface for painting.
JBL blue paint used by me was 100 grams of RAL 5007 with 3 small drops of white paint in it.The result was really astonishing ... is was almoust 99% JBL blue.
After that I cut the edges at a 90 degree angle and now I'am preparing to repare the corners and holes between the plates with a special wood paste.
I will keep you posted here are some pics. Sorry for the bad quality I made them at sunset.

mesudman
08-22-2010, 07:56 AM
I have finished painting the speakers and as you see they are starting to look pretty good comparing to their original condition.
So what do you think about their new color? It's almoust like JBL Blue :)
At the beginning of the week I will mount the veneer and oil them.
Why do you think the last owner removed the wire connection on the top of the crossover?
Take a look at the pictures and try to advise me what to do. I'am not skilled in wire connection and electronics but I want to make them complete as original condition.
I'am counting on your help .
Thank you guys

spirou38
08-23-2010, 12:42 AM
I have finished painting the speakers and as you see they are starting to look pretty good comparing to their original condition.
So what do you think about their new color? It's almoust like JBL Blue :)
At the beginning of the week I will mount the veneer and oil them.
Why do you think the last owner removed the wire connection on the top of the crossover?
Take a look at the pictures and try to advise me what to do. I'am not skilled in wire connection and electronics but I want to make them complete as original condition.
I'am counting on your help .
Thank you guys

Nice job !

As 2 of them are broken, you should change the 4 binding posts on the both speaker so that you could insert good spaeker cables. But be careful, you have to use insulated binding posts because ( if my mind is good ) the black paint has beed applied on an aluminium sheet !!!

Pascal

mesudman
08-24-2010, 12:08 PM
I manage to solve the problem the top conectors were simply removed but the conections are good.
Thank you very much Pascal you and richluvsound gave me the guts to begin restoration.
It was a lot of work but finaly it will worth the trouble.

richluvsound
08-24-2010, 01:03 PM
We all have to start somewhere . Thats a great start . CC them babies and your laughing :D

Rich

mesudman
08-26-2010, 10:37 AM
now comes the hard part... fixing corners and repairing edges with wood paste.
After comes veneering.
Hope everything to end ok :)
I will post pictures.

richluvsound
08-27-2010, 02:46 AM
just a tip from experience . USE CAR BODY FILLER , much harder than wood filler - mix it with a little polyester resin ( fibre glass resin) This stuff holds a very strong edge and still easy to sand .

Rich

mesudman
08-28-2010, 11:48 AM
I did it ! I bought fiber glass paste with car body filler and did exactly as you said.
The result was astonishing ! I manage to rebuilt the corners and edges really good. After sanding they were perfect and strong like cement.
Your idea was great !
You guys really helped me a lot in my restoration project and I really owe you a lot !
Many thanks and I will keep you posted with more pictures.

Alex

Rolf
09-05-2010, 01:51 AM
Congratulation on your find. The next step is to remove the original network, get a pair of CC Network, a electronic x-over, bi-amp them, and you will very very happy.

mesudman
09-10-2010, 02:13 AM
If the sound will be improved I would be happy to do the changes...but I need someone to explain the procedure and tell me exactly what to buy.
I wait for your advice.
Thanks ,
Alex

richluvsound
09-10-2010, 03:30 AM
Hi Med ,

Step 1, sweep test all components . You can download a sweep test from the web , The woofers need a re-cone IMHO .

step 2, think about your budget. CC networks will cost you 4-500 euros each. If you can do it yourself even better . There are schematics here on the forum .

step 3, Electronic x over and amps . What do you have as far as equipment and what do you want to spend.

step 4, Get them min 300 mm off the floor :applaud:

PM on its way , Rich

mesudman
09-11-2010, 12:17 PM
It took a lot of work but finnaly my babies are again beautifull :D
I instaled the drivers and get them working again and now the next stept will be testing to see if they work perfectly.
Here are some pictures ,
Thanks guys

hjames
09-11-2010, 01:09 PM
It took a lot of work but finally my babies are again beautiful :D
I installed the drivers and get them working again and now the next step will be testing to see if they work perfectly.

Thanks guys

They are beautiful indeed!:D
If they sound half as nice as they look, I'm sure you'll be VERY happy with them!

richluvsound
09-11-2010, 01:36 PM
:applaud:

Wonderful work my friend .... they look stunning .

Rich

mesudman
09-11-2010, 01:49 PM
:bouncy:
thanks guys
Now I'am searching for some nice stands or a schematic to build'em myself.
Any suggestions ?
Thanks,
Alex

richluvsound
09-11-2010, 02:34 PM
Alex ,


these will cost a bit in parts ,but well worth it !

http://audioheritage.org/vbulletin/showthread.php?166-4333-S300-L300-equivalent-bandbass-circuit&p=1042#post1042

Stands just take a little imagination. How about 4 concrete blocks ....covered in mdf or ply ,then veneered .... or some big chunks of solid timber ..... whats around you .... You could cast something in concrete or weld something up .... What skills and tools do you have ?

Rich

mesudman
09-11-2010, 03:24 PM
I don't have the tools and I not very skilled but I have a friend that can make them for me. He has all the tools and some skills. I just need a schematic for nice looking stands. I want to build something that will also look very good.
I saw the classic ones on kenricksound but I did not like them to much.
So I'am still searching....
Thanks

MickeyFinn
09-11-2010, 09:18 PM
Nice work Mesudman... they look great!

HCSGuy
09-11-2010, 11:06 PM
My favorite stands were the ones in this thread:
http://audioheritage.org/vbulletin/showthread.php?26077-JBL-4333A-AMAZING-CONDITION-3500-in-Bay-Area&highlight=4333a
Unfortunately the pictures were lost to a photobucket snafu (anybody still have them?)

They were black, the full width/depth of the 4333a's, I think about 10" high, but the front was cut like the acoustic lens. Maybe they looked dumb in person (I don't know), but they sure photographed cool...

macaroonie
09-12-2010, 03:58 AM
Lovely work there , you must be very pleased. You still need new Foilcals and grilles. Saeman here in the forum is now in charge of the blue cloth supply chain and there is a e bay seller that does the foils , sorry I don't recall his user name.
Kenrick will do you a pair of lenses but I think you already know this.
Not far to completion but the little details are a pest but necessary.
Good luck with the rest of the journey


Mac

mesudman
09-12-2010, 12:43 PM
Thanks man,
you are right they are not yet complete...
I found a stand schematic and I but I'am still searching for the grilles schematic if someone has them please help
Thanks a lot
Bye

doodle6
09-13-2010, 07:19 AM
Thanks man,
you are right they are not yet complete...
I found a stand schematic and I but I'am still searching for the grilles schematic if someone has them please help
Thanks a lot
Bye

Very, very nice job. I've been a cabinet maker for 35 years so I can vouch for the quality of the workmanship there. Extremely professional execution....

macaroonie
09-13-2010, 10:55 AM
Thanks man,
you are right they are not yet complete...
I found a stand schematic and I but I'am still searching for the grilles schematic if someone has them please help
Thanks a lot
Bye

Rick ( Saeman ) has done many large format monitor restores and builds. If you search through his posts you will see how the grilles are done , he has posted many pics in the past.

http://www.audioheritage.org/vbulletin/showthread.php?6684-JBL-NOT!!-DIY-4351-Studio-Monitor/page6&highlight=saeman post89 should give you enough clues