External DAC For Oppo 105 At What Cost?

It all comes down to personal preference. I'm using MW Sony 5400 with the updated PS 9.9 and I prefer it to all of the Dacs I've owned to include EE, Bryston, Berkeley and the Lampi Amber upgraded/equivalent to the Lvl 4 Gen 5 with a Tungsol rectifier .

They all were refined and sounded pretty good but at the expense of a much smaller soundstage and a decrease in impact. The MW soundstage was much larger/fuller and that's why I'm hesitant in trying any other Dacs or MW new Dac, because I'm happy with the sound of my spinner...   

I use a 105 as a transport and output everything over HDMI into my Bryston DAC3.  All High Rez silver discs and downloads play at native resolution, and the Oppo outputs DSD from SACD over HDMI.  That would be my advice on getting the best from your Oppo

I had the same issue with my 105. Strongly suggest you NOT modify it, but find the right DAC. It is not hard to outperform the DAC in the 105. I use an LKS that beats the 105 by a mile, but it’s not for everyone. If you decide to sell a modded 105, you will never recover anything like the cost. If you buy a good DAC it will give you many more options as your digital universe opens. I’ve moved way past the 105 using it now for video and for ripping SACDs.

As for which DAC, that is such an open question that there is no right answer for everyone and every system.  You'll have to do your homework.  Two people will compare two DACs on different systems.  One will hear no difference; the other will hear a great difference.

I don’t know why folks on this board are so resistant, but the best SQ (as well as ease of playing) is gotten by getting rid of "players" and ripping silver disks.and sending the files directly to the DACs. The silver disks add nothing, only detract.

670 bucks for a Denafrips Ares will do it. outperform the internal dac in the 105 player.