バッハ 2声のインベンション BWV 772a ~BWV 786 BWV 772a BWV 772 01:35 BWV 773 02:48 BWV 774 05.38 BWV 775 06:51 BWV 776 07:40 BWV 777 08:58 BWV 778 11:59 BWV 779 13:50 BWV 780 14:44 BWV 781 16:54 BWV 782 17:35 BWV 783 18:52 BWV 784 20:28 BWV 785 21:38 BWV 786 23:09