Please don't be offended, but that's kind of like asking what's the best car for use on paved roads. If you hope to get any meaningful feedback at all on this kind of question you need to provide quite a bit more data.
I have Ariel and Me2 speakers they are powered buy triode strapped el34 pp amps at 14 watts output. I use them for music only. my room size is 15 feet by 12 feet want to add a powered sub any recommendations would be appreiciated.
I'd probably look at things like the CSS SDX series...Mach 5 Audio IXLs...Exodus Tempest-X2 and Shiva-X...the list goes on. Plate amps can be found from Parts Express or Apexjr.