You'll also need a 1/8" stereo to 2 1/4" jacks in order to play back through two channels. Also a 1/8" to 1/8" stereo if you want to play through your car radio (if it has an auxiliary in). I would also get a 1/8" inch to two RCA jacks, so you will have every situation covered. Radio Shack has them all.
DonM