Sony on Wednesday revamped its AV receivers for 2011 with four seven-channel models that lean heavily on the purely digital side of media. Aside from the entry DH520, the DH720, DH820 and DN1020 all take in iPhone or iPod audio through at least USB and, with the DH820 and DN1020, through a bundled dock. The DN1020 as the flagship is also designed for Internet radio from the start and will pipe Slacker or vTunes when linked up over Ethernet.
