@nyev
A couple of observations and a little cajoling to follow.
First of all, the Merason DAC1 can be end game for some but based on this thread, it was likely to never be more than an external dac proof of concept in your system. You needed and deserved a reference point to see where your internal dac board measured in comparison. You have discovered that it will stack up nicely and that its merely different. In fact, there is a growing body of evidence among many users that zoning in on bit rates rather than the sound as a whole to be an unfortunate use of one’s time. Does it sound great or not?
When you get your MU1 and the fancy cables, set the MU1 for 2fs and forget about it for a while. Do NOT do any upsampling via Roon…that would be the wrong direction since the MU1 will be your Roon core the anticipated benefits of doing so in my opinion would not outweigh the negeative impact caused by taxing the cpu. I can switch between 2fs and 4fs on the fly and I find the differences to be so minimal that its probably confirmation bias on my part. YMMV.
There are numerous exceptional dacs on the market in the $10-20k range. The MU1 will help you determine if the Gryphon dac board can be satisfying to your ears and be a stopping point for you, however, if you find the Merason more satisfying than the Gryphon dac board then all you’ve learned is a pretty decent external dac is better than a pretty decent dac board. Then you would likely begin trying different external dacs. Ive had too many dacs to re-count for this thread…most of which presented my music wonderfully: Lampizator, Nagra, Playback Designs, Chord Dave, Meitner, etc, etc. I’ve settled in with Totaldac, others have settled in with other brands and found happiness. Thats what its all about. Settle in and listen for a while when the MU1 and your cables arrive. Set the MU1 for 2fs and forget about it. Do you like what you hear? Do you like it a week later?
At the end end of this next phase of this exercise you will discover a few salient data points.
1) Does the MU1 maximize the performance of your Gryphon dac board and is it enough to be a stopping point for you?
2) Does the Merason improve upon the Gryphon dac board to the point that it leads you to believe the apex performance of the dac board is more similar to the entry point of better dacs?
3) Is the cost differential and added complexity worth it to you?
4) Keep it simple, you won’t learn nearly as much about a future spouse by speed dating as you will if you take the time to get to know them well. The same applies here.