My JBL 4343 repair story

[y60kuro]

I got sheep wool insulation for my 4343. This is made for audio insulation (25mm thick, natural sheep wool 85% ) . Good by tired , strange smell , living germ yellow original glass wool insulation. 　I calculate the required area of about 15,325 cm2 in the body on one side, mid-box back is 3,045 cm2,　 total by a pair 36,740 cm2　. Mid inside 2,570 cm2 in pairs.....


*4343　body :15,325 (cm2/one side)-----30,650(cm2/pair)
*mid box outer:3,045 (cm2/one side)-----6,090(cm2/pair)
*mid box inside: 2,570 (cm2/one side)-----5,140(cm2/pair)
-----------------------------------------------------------
total 41,880(cm2/pair)

This box inside 30,000(cm2). Shortfall there is no dealer stock will be at a later date.

[ARMED]

keep up the good work man!

[y60kuro]

I was fixed with a staple of the insulation.

[pyonc]

I was fixed with a staple of the insulation.

Nice!

[y60kuro]

A little time passed since last post.

My 4343 repair is ongoing.

[y60kuro]

Remove ripe urethane edges　2121　



x2

[JeffW]

Good to see you are making progress, nice work!

[y60kuro]

Good to see you are making progress, nice work!

Thank you JeffW　

[y60kuro]

[y60kuro]

X2

Need twice times as 2121

[hansenni]

Well done

[laszlo]

amazing job!!!

[Flodstroem]

Compression drivers including UHF drivers does normally not need any re-charging of the magnet because Alnico V is very stable
when used with those small electrical induction levels in the HF and UHF frequencies
But those 2231A could have loosen some of the magnetic charge due to large electrical inductions from the voice coil so a re-charging of the magnet could probably be beneficially. It can be done with voice coil and cone mounted in the basket. No need for to take it out.

Btw, A hell of a restoration work for you, and it looks very very good so far

[y60kuro]

Well done

Thank you hansenn

amazing job!!!

Thank you laszlo

Compression drivers including UHF drivers does normally not need any re-charging of the magnet because Alnico V is very stable
when used with those small electrical induction levels in the HF and UHF frequencies
But those 2231A could have loosen some of the magnetic charge due to large electrical inductions from the voice coil so a re-charging of the magnet could probably be beneficially. It can be done with voice coil and cone mounted in the basket. No need for to take it out.

Btw, A hell of a restoration work for you, and it looks very very good so far

Thank you good knowledge Flodstroem
I will do re-magnetize 2231A or change LE-5A . it is first time to do this job for me , remove and clean up unit frame was so hard to my finger

[y60kuro]

Fix edge and cone first .




Leave overnight　my 2121