By Jessica Brown, 23 October, 2014 Forum macOS and Mac Apps Hi. Subject says it all. I have a bunch of cassette tapes I want to make .mp3 copies of. How can I do this and what will I need? Thank you. Options Log in or register to post comments Comments My suggestion Well I've never done something like this but I will try to help. I would think you'd need a casette player, a cable to connect it to your computer, and perhaps an audio editor like Garage Band. Here's an article that may shed some more light on this subject. http://www.wikihow.com/Transfer-Cassette-Tape-to-Computer Good luck! I tried the same I needed to do the same thing. I first wanted to connect my cassette player to my laptop using a 3.5 mm plug, but that didn't work for some reason. I took my plextalk pocket and recorded with the line in of that, and than copied the files to my mac. It should be possible to use the headphone plug as a line in, but when I plugged a cable in there, the speech was lost so I couldn't really figure out what I was doing. External Sound Cards may help If you want to use the headphone jack as a line in or if your computer has no line in, an external sound card may do the trick. Some of those have line-in jacks on them. Sound card questions Hi. What sound cards have 3.5 mm line in jacks? Also, is there a way to set recordings to go through the sound card, but still have VoiceOver and system sounds and other audio like music still go through the speaker built into the Mac or headsets connected to the Mac? Thank you.