So we can easily deduce a conclusion by this thread, that Pontus II is definitely a big upgrade from Ares II, and whomsoever thinking to get into R2R sound should strongly consider getting a Pontus II rather than an Ares II.
Now the newer Ares II 12th anniversary has more power which reduces the gap to the Pontus II.
So yesterday I ordered the Denafrips Ares II 12th anniversary (more power, better firmware, and i2s input) which reviewers say sounds even more realistic than the original Denafrips Ares II. I'm looking forward to hearing the Denafrips (R2R technology) compared to Delta-sigma chip based from ESS Sabre (I have the Topping E50, Topping E70, Arcam AVR5 receiver that has the ESS Sabre 9026Pro).
I do NOT recommend my Denon X3700H with an unknown dac that is not dynamic and sounds terrible for 2-channels music.
I do NOT recommend my Emotiva BasX-A3 amplifier because it is not dynamic and sounds terrible for 2-channels music.
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..I upgraded to Apple Music... and wow, just wow.
Apple Music with Spatial Audio (surround sound music via Dolby Atmos) is a night and day improvement.
Spotify 2-channels is like home theater in the 90s with 2 front speakers or DVDs, whereas Spatial Audio is like today's home theater with 13 speakers and Dolby Atmos/DTS:X and 4k physical disc movies. It's a night and day improvement.
I compared the song 'Senorita by shawn mendez and camila cabello' in Apple Spatial Audio versus 2-channels Spotify and it was a night and day improvement.
In my Corvette with Apple Carplay (and an aftermarket wireless Apple Carplay adapter from Amazon), Spotify now sounds so so so bad (sounds like a cassette as if there's a blanket over my speaker) versus Apple Music's clarity and dynamic range. I didn't know what I was missing!
The song with the most night and day difference is: Y Volvere by Lucero (female vocalist). In Spotify, there's a lot of crackling noises because Spotify can't capture the full wavelength, whereas there's no crackling in Apple Music and the notes are higher.