The Quartet are excellent speakers. An acute precise, a medium and an amazing deep bass. Listening is perfect quelquesois the type of music. Miles Davis Coldplay, Ray Charles, Dire Straits, via Vivaldi, Mozart and JM Jarre ... listening is captivating.
Note that it is certainly preferable to associate them with an amp that is not "too dynamic". For me it is a Luxman LV105u old man who has proven.
I also had the opportunity to make a play with a 100% tube amp combined with a Rega CD player. A real treat ...