Had 2 session good listening :
AK SP2000 Cu
I can said 80-85% similarity between SP2000CU (SP) and DX221mk2(DX). IMHO.
SP Bass give a bit more detail then DX. But Bass weight is equal.
Mid/Vocal, both of same position, SP give a bit more Depth.
Treble somehow is very similar, What I noticed, SP is more airy side while DX is more on spark side.
SP soundstage a bit wider, Airy effect...
Now This is the fun side for me... SP2KCU has waterfall HISS with solaris just like DX221mk2, well tbh, still quiter then DX... =)
Power / Dynamic, SP seems a bit more lust...
So if the rest 15-20% is it worth the 3x price?
The second, Was trying SP2KSS... hmm well it's quite different SoundSig then the SP2KCU, It was more on Mid/Vocal oriented.
Best pairing with Tia Fourte and PWGold26.
Even when tried the IEM and Cable to DX221mk2 still the best Mid/vocal experience I ever heard....
Going back to Solaris, hmm.. it was different level... regret feeling comes to me that I had tried that combo... need to reset my ear again....