This beautiful collection of the complete solo piano works of Beethoven, by the wonderful Rudolf Buchbinder has all the major works, of course, including masterful renditions of the 32 canonical sonatas, all the variations (including the big ones, like the Diabelli), etc. But it also includes a number of distinctly lesser-known works, including this month's clip, the first of Beethoven's two Preludes through all the Major Keys, op. 39. Technically, the preludes, of course, do nothing of the sort, but they do do so enharmonically. (A bit of an über-geek point, but the array of major keys is an infinite collection, and even the so-called non-theoretical ones include 15 keys, not 12. Anyway, I digress.) The first prelude is a good bit more developed than the second one, and, in contrast to the second prelude, most of the motions smack significantly more of modulation than tonicization. In either event, they are both quite interesting to go through, if for no other reason than to give a good summary of basic modulatory technique.