The Clip Sport and the Clip Jam have the same processor. The Clip+ and Clip zip have the same processor. The processor in the Clip+ and Clip Zip has greater capabilities, however it also consumes much more power than the processor in the Clip Jam or Clip Sport. The Clip+ and Clip Zip have battery life listed as 15 hours, while for the Clip Sport it is 25 hours, and the Clip Jam 18 hours. I have the Clip+, Clip Zip, and Clip Sport. my Clip+
and Clip Zip have Rockbox installed. Rockbox is a free alternative firmware(operating system) for the player that offers many more features and settings. It is not available for the Clip Sport or Clip Jam, due to the less powerful processor they have. The Clip Sport is rather similar to the Clip Jam except that the Clip sport is slightly larger and has a larger display.
The Clip Sport and Clip Jam keep the contents of internal memory in a separate database from that of the songs on the card. Playlists can only contain songs from one or the other and not both. The Clip+ and Clip Zip integrate the songs from internal memory and card memory. Those who want to have 2,000 songs on a Clip Sport or Clip Jam and shuffle all the songs would put all the songs on a card in the player. There is a new experimental firmware for the Clip Sport that raises the database limits to 4,000 songs for each.
The Clip+ and Clip Zip can play protected WMA files which the Clip Sport and Clip Jam can’t play.
Of the Clip+, Clip Zip, and Clip Sport, my favorite is the Clip Zip. The extra battery life on the Clip Sport is nice though. For those who don’t plan to put over 2,000 songs(or perhaps 4,000 using the new exprimental firmare) on the player, the Clip Sport is likely to be good enough. I wouldn’t get the Clip Jam though as it is basically a Sport with a smaller display and less battery life.