In this week’s iTunes Essentials is  Tchaikovsky’s Swan Lake, this definitive performance by the London Symphony Orchestra and conductor André Preven glows with elegant charm, sprightly rhythms, dramatic climaxes and – above all – unforgettable melodies. Itunes Classical Music Essential  helps to navigate  vast array of choices, by presenting superlative performances of essential masterpieces, all from high resolution master recordings, and all Mastered for iTunes.