Emanuel Ax obviously loves Haydn's piano sonatas. This is his second CD of them, and I wouldn't be surprised if he had to argue with his record company to make the discs; Haydn doesn't sell nearly as well as Mozart. But each of these sonatas is a genuine masterpiece, filled with imagination. And, frankly, quality aside, Haydn's piano sonatas are less predictable than Mozart's, less regular in form and quirkier. Ax plays the music fairly straight, expressively but without romantic mannerisms. This is a thoroughly enjoyable disc, and maybe if enough of us buy it Ax will be allowed to make another one. --Leslie Gerber