My JBL 4343 repair story

[y60kuro]

Hello all

I am from Japan here nice to meet you . sorry poor my English I must say first. This photo is when I first met with the my 4343 . I heard this 4343 is sleeping in a few years in the my friend's garage in this state, so I went to see. The Urethane edge (2231A,2121) was damaged by aging. However, since the overall condition was good, have to be working to repair it myself, I decided to pick it up to my home. 　4343 was released 1976 in Japan , hear to have been about a million sets import. JBL was surprised "so much whether the studio is located in Japan ?" . In fact it seems audiophiles had been bought as a status. but it is so expensive (about $5000 /piece 1978) those days . This 4343 is one of them . I will try to introduce a state of my 4343 repair story of here.　

Regards

[mortron]

You got all the good cars already over there... now I find out all the good speakers are hiding there? I need to get back in touch with my friends over there and see what's in their garage

Gonna be a great project to work on with great reward. Looking forward to following.

[JeffW]

Your English is fine, welcome!

Those 4343 appear to be in nice shape, the restoration should be fairly straightforward.

Congratulations on some very fine speakers.

[y60kuro]

You got all the good cars already over there... now I find out all the good speakers are hiding there? I need to get back in touch with my friends over there and see what's in their garage

Gonna be a great project to work on with great reward. Looking forward to following.

Hi mortoron
Thank you your comment. My old nissan safari LWB works good for JBL transporter .Yes there is so many good speakers sleeping now . DIATONE,SANSUI,YAMAHA,,,,etc . When do you come from here ?

Your English is fine, welcome!

Those 4343 appear to be in nice shape, the restoration should be fairly straightforward.

Congratulations on some very fine speakers.

Hi JeffW
Thank you your comment . Here is humid weather than USA so this humid is problem . bolt and unit rust ,box damage etc,,,, my 4343 has rust and little crack on the corner connection point . yes, 4343 is very nice shape I love this one. my 4343 has some problem but repair is my fun too.

[y60kuro]

The day came I took the 4343 to my home from a my friend's garage. Transportation was done on my nissan. And laid down next to fit into the luggage compartment. Woofer and mid-bus(2231A,2121) for the protection and for total weight off so these unit put off. Since remove these large units then turn off the under 70kg and can move and handle easy by myself.




The urethane edge of the unit had been destroyed in the aging. In order to prevent the voice coil in the vibration hurts, leave connection each terminals. Unit caused the repulsive force of the electromagnetic induction in doing so will stabilize, it is apparently difference you know. packing is OK, take into the cargo space , tighten by belt , let's go my home .






The garage becomes lonely no longer stay　4343 , but my friend are willing it is the best 4343 will be active again. However, this 4343 is the speaker is a presence.

[y60kuro]

Once put the 4343 in the garage, I will try to the maintenance of the unit and give the wax into the box of walnut. I've hidden units into the VAN cargo so as to defense from my boy and girl mischief .





Oh! what a very unpleasant. One of the top that had been put in the back, crack was in the right corner. Apparently the full-length seems to have peeled off from the adhesive surface is about one-third of the piece. This was at a loss. A new work has been increased. The need to remove the front baffle to also check the situation from the inside came out. 　Perhaps Years of humid and 40 years have damage to the adhesive and the panel.　In hot and humid in Japan, that has damaged the interior of most of the JBL is clear from this thing.

[berga12]

this "crack" seems more a Fall down from one side of the box.

with a cutter I would clean the crack as much as possible, insert a lot of Glue and clamp the box together, then during clamping and drying like you wrote, open the front baffle and reinforce from inside with some brakets (L shape).


Again, don't touch the blue looks superb.

[y60kuro]

this "crack" seems more a Fall down from one side of the box.

with a cutter I would clean the crack as much as possible, insert a lot of Glue and clamp the box together, then during clamping and drying like you wrote, open the front baffle and reinforce from inside with some brakets (L shape).


Again, don't touch the blue looks superb.

Hi berga12

Thank you . Yes I checked this crack depth by wire it is so deeper than I thought My face is JBL blue . The outside of the crack to adhere to as small as possible, I will try to reinforce the corners of wood from the inside. Also coated with urethane varnish to the inside to the future of humidity measures. It deviates from the original, but, Ok in the remake. By the way ,I boy's name is "Ken" . This is KenDad sound

[y60kuro]

The first is scheduled to open did not. But opened the baffle in order to see the situation from the internal crack is found. Removal of the woofer, removal of the front baffle is referred to as a daunting task in the 4343 owner our Japan　. I can open and easy for 30 seconds in the assistant help.







Hello guys nice to meet you !

[ARMED]

y60kuro, do you mind measuring how long the ports are..please, thanks!!! i know they are 4 inches diameter

[y60kuro]

y60kuro, do you mind measuring how long the ports are..please, thanks!!! i know they are 4 inches diameter

Hi ARMED
OK, It is very easy for me . please wait a moment

[y60kuro]

port inner dia:4 inch

Total lengthface-port end :210mm


face inner-port end :184mm


face inner Fig


face-port face :7mm


baffle thick :25mm


Is this OK?

[ARMED]

8.25 inches long..........(8.26 inches)??

[ARMED]

arigatou ne...

[y60kuro]

8.25 inches long..........(8.26 inches)??
is that right?
can anyone confirm?

Yes　8.26 inch (include baffle surface + duct length)