The dirty secret of the Billboard classical charts is that album sales figures are so low, the charts are almost meaningless. Sales of 200 or 300 units are enough to land an album in the top 10. [Hilary] Hahn's No. 1 recording, after the sales spike resulting from her appearance on Conan, bolstered by blogs and press, sold 1,000 copies.
The full story is here. And:
In early October, pianist Murray Perahia's much-praised album of Bach partitas was in its sixth week on the list, holding strong at No. 10. It sold 189 copies. No. 25, the debut of the young violinist Caroline Goulding, in its third week, sold 75 copies.
I buy a lot of classical CDs, but it's rare that I end up listening to such chart-toppers, instead preferring more obscure performers.