I have owned my Sierra 1s for about 4 or 5 years and I love them.
I was feeding them through Marantz monoblocks connected to a Yamaha Aventage receiver. They sounded amazing.
Today, the receiver and amps were replaced by an Anthem MCA 30 amplifire and an Anthem MRX Receiver. Holy crap! They love the Anthem gear. The midrange and bass were greatly improved; especially the detail in the bass. The speakers became more revealing. I'm hearing stuff I never heard before in music that I've listened to for years and years. Snares are greatly improved, as are guitars; I don't know why, but both Nick Drake's and Mick Ronson's guitars are so much more detailed and granular. Bass guitar is more musical. Vocals are more sonically accurate. Drums have a more studio sound.
I can't wait to get through all of my favorites.
If you power your Ascends with Anthem, I would like to hear your opinion. If not, this thread may give you a reason to audition.