Hello I am new to this site. I am in the process of building and upgrading a system. I am currently using an older NAD integrated amp with a Rega Planar 2, moon 110 phone Pre and accent Acoustic Sierra 1. I just bought an older Nakamichi PA5 amp and a blue sound node 2i. I am looking for a tube preamp and thinking about Kef LS50 metas. Any thoughts from the group?