JBL L26-3-way, modded by David, France

Copyright 2020 © Troels Gravesen

Hi Troëls,
 
I have your crossover kit you developped for the JBL L26 3 ways, and installed them yesterday, as is, without other modification, in my original L36 decade.
The sound with the original crossover is really impressive but tiring due to the exagerate amount of medium and hight frequencies: they were to much yelling!
With your crossover, what a very good suprise, my ears tells me they fit perfectly to the L36, and they really sound very good now, so equilibrate in frequencies and also they keep this characteristic good JBL sound that I love so much.
 
I had done a first attempt with those components many years ago when I bought them. But I wasn't satisfied and didn't have time to continue to investigate.
But today I know I have made some bad polarity connections between your crossover and the drivers.
After checking and understanding that all black wires of the original JBL N31 crossover went to the real positive polarity of the L25-4, LE5-6 and 125A drivers : I reconnect yesterday your crossovers as on your schematic. And today those old JBL sound for me really really good!!!
 
Here is a link to a precious JBL document, I suppose you already have: just to share it with others. It includes explanations on drivers polarity and transducer acoustic equivalent
http://www.cieri.net/temp/JBL_Reference_Information_for_Reconing.pdf
 
Actually listening to the album "Chambre avec vue" of "Henri salvador" : this recording is good, wouah!
 
The JBL are drived with a Sansui AU-G99X (2x160 watts on 4 ohms amplifier). They enjoy also a Yaqin MC-100B (KT88 push pull valve amplifier).
 
Next job for me will be to replace again a suspension foam on the bass driver 125A (the other one is already done)
 
I attach to this email a picture of the cross over screwed in the back of the L36 unclosure, and the temporary speaker installation for today's music listening in my living room.
 
If one day you do the same on the 4312 model, I woud be interested!
 
Thank you so much Troëls for the very good job you did on this JBL upgrade! And I wish you a long life to your passion.
 
Best regards
 
David from France