I don't have experience with Ares II+ but love the synergy with Eros II+, which warms up U18t nicely. It's not really "dark", but I believe it makes the sound signature closer to what you described.i dont like too much bass and prefer a flat signature. The U18's are great but i just want to feel more of the bass guitar in a few of my tracks. I like the sig of the m15 more than the m20. when i turn up the player it opens up the U18's but its too loud(i want access that openness at a lower volume). On my 1Z SE, i listen to the volume at 19, but its way to low for the U18's. On my layla's i never go above 29 clicks on the volume unless i am listening to classical. on the U18's i have to go to 29 and higher. I like a darker sound sig for certain tracks, @Giraku might be the best or anyone with the laylas or a similar sig, will the Ares ii+ cables come close to this sig? I like the U18's for my vocals but if the Ares ii+ on 4.4 balance gets my closer to a darker layla sig I will order the cable tonight.
BTW, you are listening at very low volume. I assume the numbers are on WM1Z SE with regular gain. I'm always using high gain and the number is between 50 to 80 on U18t. On 4.4 balance with high gain, I still go with 48 to 75 on U18t. I hope that APEX technology prevents me going to lose my hearing...