Alright, finally my Art Audio Jota BX arrived with the KR300B tubes. I hooked them up last night and was totally shock with the sound. The J2001-MKII SAP speakers was awnsome. With the 300B tubes output from the amp, the mid & high range are just to die for. The speakers finally come to life.
For now, this is one of the most ejoyable system I ever set up. (BAT-VK-D5 ->Emotive Sira LE -> Art Audio Jota BX -> SAP J2001 MKII). I've been listening to some other equipments (JM Lab Utopia, Kharma Ceramique 2.1, Cary SLP98, Cary 805C, Conrad Johnson 8A, Cary 306-200.....) but now, finally, this system is a "keeper".
Only upgrade I might think about is power conditioner and another Jota/other amps for bi-amp to increase a little more bass.
Also, will get my phono (Jota Saphier III) this weekend :)