I've owned the CD-120 Linear, and it's a great player. But mods would most likely be limited to the power supply and reducing or eliminating noise and improving regulation.
Additionally, you could always look to upgrade the clock.
The CD-120 Linear has no op-amps and very few capacitors, and signal paths are kept very short - in all a very minimalist design that is quite effective.
I'm sure there are those out there that would offer mods for the player if you were to inquire. Many, however IMHO are not cost-effective. I have always done my own CDP mods.
Additionally, you could always look to upgrade the clock.
The CD-120 Linear has no op-amps and very few capacitors, and signal paths are kept very short - in all a very minimalist design that is quite effective.
I'm sure there are those out there that would offer mods for the player if you were to inquire. Many, however IMHO are not cost-effective. I have always done my own CDP mods.