Today, I got a new toy - Cypher Labs AlgoRhythm Trio, I paired it with my Fiio X5. I started it with my AKG K812, it sounded  a little bit more warm and tasted more rich than AlgoRhythm Duet. Since the K812 is so perfect of vocal, it doesn't give me much new experience than the Duet except it soften some headache high pitch noise from the songs. Then, I switched to Sennheiser HD800, it make a big difference for me. I always think the HD800 is extreme analytical and it is a monitor. After the HD800 was warmed by the Trio, It sound a lot better for me. The sound stage, clarity and all the details are still there but now it is more warm like a human not only a machine. So good. At the end , I switched to my AKG K3003i, similar to the K812, the only improvement is "soften some headache high pitch noise". It is important since the K3003i is very sensitive IEM. Based on my taste:
 
       For enjoyment, I would like
               AlgoRhythm Duet with AKG K812 or K3003i
               AlgoRhythm Trio with HD800 or K3003i
 
       For analysis, I would like 
               AlgoRhythm Duet with HD800 or K3003i