The Thiel 2.4s are great speakers. I've had a pair in my main rig since 2011. The key is to have a true high current amp that can handle the fact that the speaker impedance falls to something less than 2.8 ohms at 600 hz (see the Stereophile review for John Atkinson's measurements). I first drove them with a Bryston 3BST which was decent. As of last year I've been using a Coda CSIB integrated amp, and it's an absolutely great match. I suggest reaching out to Yamaha and getting a read at how well the Yamaha amps do with nominally 4 ohm speakers with impedance that drops below 3 ohms. The Thiel speakers are awesome, but the impedance curve is simply wicked. They work best with an amp whose output continues to double down as you halve the impedance.