Hi everyone, I'm also trying to find a good dac that works ok with my burson conductor 160d amp (and lsa hp2 ultra headphones). And I don't know which one to purchase: smsl su-9, topping d70s mqa or Gustard x16. I've tried with ifi zen signature v2 and sound was very very good for me, but I need bt and optical input. Any suggestions? Regards