Don't they use additional wires though. I believe the devices with the 30 pin connector passed analog audio over a couple pair of pins. The new connector on the new products eliminated this. That is why the lightning connector to 30 pin adapter is so expensive -- it has to have a DAC built-in. I thought the 30 pin devices had the ability to pass audio either as analog or digital whereas the new lightning only passes digital.
I had a professional audio interface that used analog audio pins to get audio in/out of an iPhone 3G. When I upgraded to 4S, it was rendered obsolete because the new phones only supported USB audio. What a mess!
