A massive set--67 string quartets on 21 discs in a budget-priced, shelf-friendly, compact box. So the obvious question is: do you need it? The equally obvious answer is a resounding "yes" if you love these endlessly inventive quartets and if you appreciate superbly played performances that capture both the letter and the spirit of Haydn's genius. The Angeles String Quartet isn't as well known as some ensembles that have recorded complete Haydn sets, but they are superior to all, with the arguable exception of the Tatrai Quartet. They demonstrate technical polish and rich, warm sound that's never cloying. And they give these works the forward-moving impetus they need within a classical framework, eschewing both anachronistic Romanticism and the mechanical astringency of period specialists. 　　  　　The Angeles Quartet is unique in its mastery of early as well as late works, in tune with Haydn's stylistic development and sensitive to the attractions of each of these remarkable pieces. So they infuse the visionary slow movements of the late quartets with the appropriate depth and at the same time revel in the muscularity of the Opus 76 No.2's catchy Menuetto, the humor of the "Joke" Quartet, Opus 33 No.2, and the power of the Allegro con spirito of Opus 76 No.1. Most impressive is their way with the early quartets--no small matter when you consider that the contents of the first six discs precede the Opus 20 set generally considered as signaling the maturity of the form. The Angeles make even the earliest quartets, five-movement divertimentos for four strings, a habit-forming delight. Their playing here is full of exuberance, wittily playful and rough, peasantlike by turns. The sonics are outstanding, too, well-balanced, warm, and lifelike. An indispensable recording. --Dan Davis