Portable MP3 players allow you to carry your personal playlist with you wherever you go with the aid of headphones. Although you can find high-quality headphones, they don't have the same sound output as large stereo speakers. If you want to listen to your MP3 files on a stereo or connect it through a power mixer, you need to have the proper cables.
Use the 3.5mm RCA adapter and connect the single end of the audio cable to the headphone jack on your MP3 player.
Insert the RCA plugs into their appropriate slots on the stereo system. Sometimes they will be color-coded. They should be labeled "Audio In L" and "Audio In R" for left and right speakers.
Connect your MP3 player to a mixing unit by plugging one end of the male/male audio cable into the player's headphone jack and the other end into the 1/4" TRS adapter.
Plug the TRS adapter into the appropriate channel's input, labeled "Channel In."
Turn the stereo or mixer on, and turn on the MP3 player. Adjust the stereo and mixer volume as necessary and press "Play" on the MP3 player.
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