Quote Originally Posted by dn92 View Post
In the past I did a thread on a French forum where you can find lots of information about JBL UREI 5235, including values and frequency responses for JBL 4350 dedicated boards.https://www.jbl-vintage.com/t3066-fi...bl-urei-5235Be carefull if replacing 5532 op amp as power supply voltage can be above common tolerances of most of the op amps. In JBL UREI 5235 they can be replaced by LME49860, but also by very modern op amps like OPA1612 or OPA1656 (can be found already mounted on smd/dip adaptor). Low noise linear voltage regulators such as sigma78/sigma79 from amb lab is also an improvement.
I've enjoyed your thread through google translate yesterday evening already
Regarding replacing the op-amps - I'm actually more concerned about high frequency oscillations when using high speed op-amps. I've already seen a BSS FDS360 oscillate when used with IC's like the 4562 (IIRC) and considering there are no more safeguards between the crossover and the power amps, the crossover must be rock stable.


I found a dual OPA627 in a DIP adapter at audiophonics, haven't checked the voltage requirements yet. AD713 is borderline within spec at 18V max voltage? Also - there seem to be many variations on the AD713, the AD713JNZ seems to be the current production.