CD Direct to Mono Blocks or Preamp???

I just purchased a Pair of Dynaudio Sapphire's. I power them via Bryston 7Bst's. I'm running a California Audio Labs CL-15 (variable audio out) directly into the Brystons. I feel the Cal-Audio is the weak link and trying to decide to either replace it with another (better -suggestions??) variable out player or add a preamp to the cal (maybe still replace the Cal anyway but won't need variable out. My audio taste tends to like DETAIL !!. Appreciate your input.