Upgrade my CD player or futile effort?

I thought I would share my cd player journey.
Stage 1 were the following:
Oppo 103D SE
followed by a major step up to my
Esoteric K03xs SE
Dissatisfied with the harshness of leading and trailing edges, I sold it
Meanwhile, I have bought and upgraded two other disc players, the Oppo204 and Pioneer LX800, that were seemingly excellent with very analog sounds c.f. the Esoteric, then I caught this unit...
Audio Research Ref CD9 tube cd player and had it upgraded including renewing the power supply that failed.
Fyi, all upgrades are limited to EMI RFI control by the Upgrade Company here.
I tried various DAC’s also during my time with the Esoteric, including the Lampizator Amber III that was also an upgraded unit. Sold that too...
Most definitely the ARDC Ref CD9 SE is the most analog experience where you don’t notice you are listening to CDs. It’s seriously seductive.
The analog experience is helped by the rest of the systems variously ARC LS10SE preamp and D240 MkII SE power amp into my MB2SE by PMC. And my other system that features right now the XP20 preamp by PassLabs into the Luxman M900u feeding into some very fine horn speakers, L’Instrument by Viking Acoustics.
The bottom line is that carefully selected cd players that are synergistic with your system will and can create a fully analog sound, better than your vinyl experiences, with no pops, clicks, or dust particles to interrupt your brain’s pleasure signals.
Listening to Leonard Cohen just now his final cd... and it’s eerie, smooth mellow, and gorgeous. The super tweeters in the speakers have plenty to pick up and blow out...
I enjoy the two bcdp’s but they are more digital and less range full than the ARC Ref CD9, and this kit is still burning-in, speakers, and the CD9 player.

I have a Linn Mimik II and a Quad 99, both of which give my LP12 good competition.

Yeah, I have a Rega Apollo and a Schiit multibit DAC. Sounds wonderful! Very ‘analog’ sound. I also want to hear that Denefrips DAC. Invest in digital and it will sound fantastic. 
Sam in Massachusetts 

While a better DAC R2R ladder will help you, if you can rip all your CDs "bit perfect" into a computer and store them on a USB flash drive with a backup copy and play the flash drive through a streamer such as a Bluesound, it will not be as difficult as you think. You might even eliminate the use of the CD player. I did this with my Bluesound Vault 2i and use storage on a flash drive because that is the only way I can index my collection by composer's folders rather than by "artist and song." I stream free radio stations from anywhere in the world especially if the atmospheric conditions weaken the antenna signals from distant classical stations for my Magnum Dynalab FT 101A FM tuner.

Hi, After all I read here! There are many ways to go! I have ran the gamut of using a lot of stuff! From Dac's and Transport to highly modified CD players! The best overall sound was definitely switching to tubes! Like others have said they liked the Dac's with tubes! All you invested into analog and nothing into digital,  you really are missing out! I had a 2 piece Dac with a Levinson 31.5 Transport! The inner detail was spectacular but still not smooth like analog or tubes in  CD system! I now have an Ayon CD Tube player and it is Fantastic! Not Cheap but with top load Transport and tube Dac's! Sounds like analog without any noise! I'm an Audiophile from way back and always recommend tubes whenever possible! So if you want to hear unbelievable CD sound! You can! Also, less can be more! By bypassing my pre amp and running directly into my mono tube amps! Less Connections the better! I also recommend and use Solid Core Speaker  Cables and Interconnects! Goodluck in your search for better sound!