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View Full Version : Help!!! Need info on minor modification to L100A



henrikfk
03-17-2019, 02:56 AM
Hello,
Just briefly about myself, I live in Denmark (Scandinavia) and have been dreaming about the L100's since I saw them the first time back in the 70'es when I was a teen and had no money at all...
Since then things have luckily changed and I am now a happy HiFi enthusiast.
So, I have now been fortunate enough to get hold of an old pair of L100A's (s.nr 82527A and 87973A) and I want to bring them back to their might and glory :)
They will need some new veneer (guess it is american walnut?) on some of the surfaces, new binding posts and dampening material and two new stickers since the previous owner found the XO fixation screw by drilling through the alufoil...Have found these on eBay, they seem to be very expensive (app 50 or 60 bucks a piece)....

Anyone knowing of a more inexpensive way of buying a set?

I am also replacing L-Pad's and caps and here comes my third question:
Read somewhere (and cannot find the site anymore..) that there is a minor mod to the XO that JBL introduced to later models of the L100 I believe, something like a 0,1uF cap in parallel over one of the caps?, any of you fine gentlemen that have some information regarding data of components and how they are connected to the original components, maybe a schematic?

Thank you very much - and what a wonderful site to dig intohttp://www.audioheritage.org/vbulletin/images/icons/icon10.png
Have a wonderful Sunday and happy listening..

Malefoda
03-21-2019, 04:19 AM
Hi,
you may find that here:
http://www.audioheritage.org/vbulletin/showthread.php?3555-Bypassed-and-Biased-Capacitors

First check if not already bypassed, if not buy as much bypass caps as caps in your speakers (Polypropylene type (aka MKP) and they must be film and foil and not metallized if you want to do it well. 10/22nF range). Then solder them between the factory's caps leads where you can: strip the wires close to cap or at the soldering strips. And let us see it with nice pics ;)

Something like that:
https://www.ebay.fr/itm/10-pcs-BC-Components-MKP418-10nF-250V-2-Film-Foil-Capacitor-MKP-418/251254672669
I can have a look in my spares if you want.

script56
03-21-2019, 08:01 AM
http://www.troelsgravesen.dk/JBL_L100.htm