Responses from fiesta75

I don’t know what the opamp p/n 11-0163 is. But did you check for noise on the output of that channel? I’ve had problems with the pre-driver transistors.  
JBL d123 crossover yes or no ?
No crossover is needed for either 8 or 16 ohm version. Pretty good sounding, but they don’t cover the high or low frequencies really well. I have enjoyed them for what they are!  
Where is it going to be? I did a quick search, but it didn’t come up.  
Denon DCD-3520 CD Player
I would keep using it. If you have a problem, then you can decide if you want to repair or replace it. For equipment like that, don’t fix if it ain’t broke! I have an old Denon that still works great!  
Unscrupulous ebay buyers
I won’t sell there! Sorry I think they will just take your money…  
Ideas for Biamp with mc611 and mc275?
Yes, you will need to access the drivers and binding posts and disconnect the internal crossovers from the binding posts. Or simply add another set of binding posts.   
How do you stop house guest from damaging your speakers?
😁 grisly!  
Ideas for Biamp with mc611 and mc275?
Active is the only way to go. And don’t forget to bypass the internal speaker crossovers!  
active crossover recommendation
First Watt or Marchand would be great. Depends how much you want to spend and if you want to take time to find one used. For me, even very low cost TDM or DBX sounded better than passive crossovers. Best wishes.  
Arcam A65 with EMI driving me nuts…
Have you determined if the noise is in the power amplifier section? I would agree that EMI would be in both channels.  
Tweeter distorting question
I had a midrange from that era where the voice coil became partially delaminated from the diaphragm. I guess it could be the crossover, but I have not experienced that before. Good luck!  
In search of help or direction on Altec A-7 500 16 Ohm Magnificents.
I don’t recall Altec making a 300 Hz. crossover for the A7. Could you double check the frequency?  
Buyer anxiety
I would not complete transaction!  
Esoteric VRDS-NEO not reading discs
My experience with CD players not reading discs is the laser is getting weak or failed. I’ve had problems like you describe on other manufacturers but have no knowledge about Esoteric. Good luck!  
My Sunfire use to do that until I had Bill F rebuild it and adjust the threshold to a lower level. Cost about $260, so you might want to consider a new subwoofer. Best wishes