My Oppo is a bit too bright

Thank you all for your comments. To recap:
1. The Oppo’s DAC is its weakness and I should look for an external DAC
2. The Oppo’s DAC is quite good and can’t be bested unless I want to spend more money then it’s worth.

Fortunately this can be tested.  You can demo DACs like the Audio Mirror Tubadour Mklll SE or MHDT Orchid, etc. at home as they offer trial periods.  I’d think it’d be well worth your while to take advantage of this, and I’d be very surprised if you didn’t hear significant improvements.  FWIW.

Buy a dedicated cd player....the oppo is a do everything wonder, but not designed as a dedicated cd player and therefore is a compromise to fit all that in one box. It’s a great product, I own the 205. Better yet, get a cd transport and the dac of your choice. I’m using both a Marantz space saving cd hd1, as well as the audiolab cdt6000. For dacs, I use the musical fidelity v90 dac and a jolida glass dac, both top rated dacs in their respective price ranges. Another great dac would be a border patrol. But to be honest, when I really sit down and listen, I'm listening to LP's, analog. 

By a $50.00 tube pre off Amazon and line stage it.

Suca 1 Preamp!

Be amazed!

  I must agree , my Oppo 105D is too bright . I also tried using my Audeze headphones and what I disliked about my Oppo was highlighted. I currently run a Schiit Yiggy and a Musical Fidelity transport . Most my interconnects are Morrow . I too considered upgrading the Oppo, but at this late date , I didn’t . I’m running a Rogue Pre and a Dennis Had Inspire to Zu Omens . Even with high quality NOS tubes, the Oppo was “ Too Edgy “. I went from a Schiit Bifrost to the Yiggy and couldn’t be happier . I can’t recommend other DACs without having auditioned one in my system, so I won’t . I use a Dennis Grey power filter , Hubbel outlets , Morrow power cords , and digital specific power cords for the DAC and transport . My TT is a modded Thorens with a Grado cartridge. So by comparison streaming Tidal Vs vinyl , it’s real close . But to be fair my TT needs a tonearm and cartridge upgrade which would definitely take it up a level . So to compare Tidal Masters streaming Supertramp’s “ Crime of the Century” to spinning my Mobil Fidelity Masters record , they both sound pretty good . The caveat of my share is that I’m on level “ B “ in Stereo land and there’s a ton of sky above me . So now my Oppo is in the closet due to limited rack space . I have a large collection of concert DVD’s and every once in a while will play one . So my vote is with the “ Get a Nice DAC “ camp, as 90% of my listening goes through the Yiggy . Happy Hunting , Mike B. 

Ideas:
Try playing with the OPPO filters.
Use the balanced analog output if you can and turn off the gain control.
Don’t use ’bright’ cables - try the inexpensive Benchmark Media cables.
Get a really well-recorded SACD (Heifetz, Roger Waters, Jorma Kaukonen, or Patricia Barber) to use as reference.
Use the OPPO USB input from a Mac Mini streaming buffered QoBuz music over a CAT 7 ethernet and a 300Mb internet connection.
Use ’Pure Audio’ mode.