Setting up an alternate amp

Balanced outputs from my Ayre preamp go to an Ayre amp; single-ended go to a crossover that low-passes to a pair of subs.  I want to high-pass from the crossover to Cary tube monoblocks as an alternative to the Ayre amp.  When either the Ayre or Carys is not in use it will be in standby, and speaker leads from only the active amp will connected at any given time.  Is there a problem with this plan?

I'm using the term amp to refer to the Ayre stereo amp and to the pair of Cary monoblocks.

db