Yep, tubes. I recently had the pleasure of having an Ayre V5XE in my system for about a week. What a great amp! No hard edges or harsh clipping or anything at all to make me think of an SS amp (in the bad sense - there are certainly other good SS amps). The presentation was oh so natural and clean, yet very resolving and balanced. I would agree with Pubul57 - if you like the Ayre, and you are not, for some odd reason, going to actually get the Ayre, then I'd be looking at tubes. You will be hard pressed to find an integrated SS amp that sounds like that IMO.