Has anyone heard of this gifted young Armenian composer/choral conductor? I'm spellbound by the purity and power of the sound he gets from his chorus:

http://www.youtube.com/watch?v=hnHHb8ixAmk

At 1:50 they sing in unison with a mixed chorus. How does one get such a perfect sound from a mixed choir?

Here's Durufle's Tantum Ergo, also conducted by Vahram.

Turns out he is a composer in his own right as well.