Avalon Isis or Sonus Faber Liliam

2 great speakers with 2 different sounds its up to you i like the Avalon had another model years ago and i loved them.Good luck.

Thanks for your reply.

Presently I have a pair of Avalon Isis and would like to possibly make a change to another manufacturer as I have had them for 4 years. I might be ready for a change. I have had experience with Sonus Faber and wonder if their larger speakers sound as good as the current Avalon. I mostly listen to jazz and want good mid-range with tight bass response, no boom. Sound should be natural and non- fatiguing.

Judging by your brief description alone, I would say stick to the Isis. The SF would probably be slightly more pronounced in the high frequencies and, while quick & dynamic enough, they would not be appreciably more so than your Isis; nor would the bass frequencies be improved (although SF offer a bass amplitude control button) - maybe a tad deeper.
What may be more attractive is the SF mid-range. The SF sounds silky whereas the Isis sounds accurate (that ceramic mid...); simply put, a badly recorded violin will be sonic purgatory on the Isis but only slight torture on the SF.
Overall, and considering you listen to jazz -- i.e. you need to reproduce dynamics and nuances full-range -- you are OK as is.

If you like fast, coherent & musical sounding speakers, i'd try to get an audition of the new Magico M3's.

Magico M3 a bargin at 75k i heard them they were great still love my Q3s.