Check the first post for the replacement values of the capacitors in the pod, the PSU in the woofer case and the LFE amplifier in the woofer itself.on the mouser website, there are several types of Op amps with references ranging from 1602 to 1642.
What do you recommend for the Control POD Z5500?
https://www.mouser.fr/c/semiconductors/audio-ics/audio-amplifiers/?m=Texas Instruments&series=OPA1642&utm_id=125494649&gad_source=1&gclid=Cj0KCQiAlsy5BhDeARIsABRc6ZvETtMCl6B_s4dm2CRSgu4qaiE_wEP8Zhrz1cGo6PMrvQhuLDCqieQaAoc_EALw_wcB
And if I want to change the original capacitors in the Subwoofer, with DENON capacitors, what reference exactly do you recommend ?
I prefer a neutral amplification, you do not need to use very warm or high spec opamps. The TI OPA 1602 opamps are very good SNR and relatively inexpensive to buy and widely available. It is a class D amplifier, so more expensive opamps wont make much more of a difference - you will still be limited by the amplifier itself.