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Wagner
08-14-2015, 08:32 AM
I know much has been discussed regarding these and it appears JBL sourced them from more than a couple of vendors

I am putting the finishing touches on an old pair of L100s now and plan to keep things as original as possible (owner request) right down to the cardboard "Electro-Cap" tubes being re-stuffed

These are late model (A)s and use the "COSMOS" CAT 40 H 8ohm-50dB pot (all the late model L100s I have handled used Alps)

They sure feel like it and look like it, but I have to ask a question borne of ignorance; are all of the L-pads (and these) used by JBL during this period wirewounds?

I have no real problems with this set and plan on soaking them in De-Oxit while the balance of the work is done; as they work reasonably well I wanted to avoid opening them up

Any possibility that they are NOT wirewounds?

Wagner
08-14-2015, 09:52 AM
Think twice about these guys!
(there's an old thread here with some speculation regarding this same number):
http://www.audioheritage.org/vbulletin/showthread.php?23021-L300-Summit-MELTDOWN

SOMEBODY definitely wants them!
Parent company, "TOCOS" still alive and well and seems to be in the premium parts game
Feel a little better now about rehabbing/re-using these:
http://dailypromodealsonline.com/item/7582965.html (missing "JAPAN", this listing may be for counterfeits)

http://www.tocos-j.co.jp/e/index.html

Wagner
08-19-2015, 09:13 PM
L100(A) late model
What is the L-pad's resister value for "FLAT"?

Would like to set my knob's index mark in relationship to the scale on the foilcal as accurately as possible staying faithful to the original design

The theoretical "FLAT" or "0" setting

I ask because all 4 of my pots in rehab measure the same and match well, but all 4 are just a hair under 7 ohms

Is there a "spec" for what should be the flat setting according to JBL? The seemingly obvious 4 ohms?

After all of this time (insanity) invested in a cap stuffing level restoration of the two cap wonder network, I'd like to have the "FLAT" resistance value where JBL intended as an accurate baseline/reference electrically :)

I'd like to know that what I am hearing is what they considered to be "FLAT" on paper