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Converting audio cassette tapes to CD, MP3 and other digital formats

See more Audacity questions and answers at the Audacity Q&A.

My parents recently redecorated a room in their house. While cleaning up, they found a cassette tape wedged in a back corner, covered in thick layers of time and memory. Just looking at it, you could tell it was old: The label, originally red and white, was now pink and brown. The tape rattled if you shook it gently, not a good sign. But we put it in a cassette tape player, pressed play, and heard our voices talking back from over twenty years ago!

With the luck of having such an old tape still work, and containing rare audio of the mid-eighties, we needed to get this tape copied fast. And the best way was to convert it to a new digital format. Save your memories and convert your cassette tapes to digital media, like MP3s or CDs. With some very cheap equipment, audio cassette conversion is easy.

What you need

You'll need a cassette tape player with a headphone jack, a computer with a soundcard, the free "Audacity" software, and a 3.5mm (1/8-inch) male-male stereo audio cable. (Though 3.5mm is a standard size, your own hardware may be different.) A six-foot cable can be found for about $5.00 at your local electronics store like Radio Shack.

How to convert

1) Plug one end of the audio cable into your cassette player's headphone or "Line out" jack, and the other end into your computer soundcard's "Microphone" or "Line in" jack. To prevent possible soundcard damage, use the "Line in" jack if possible, and not the "Microphone".

2) Start Audacity, and change the input type to "Line in" or "Microphone", depending on what soundcard jack you're using. This tells Audacity to record whatever it "hears" on the soundcard input. To do this, open the Edit menu, then Preferences. You'll then see a screen that should do what you need: Use the "Device" selector to pick your input (soundcard, microphone, audio jack, etc), and change the "Channels" selector to pick from mono or stereo recording.

3) Press the record button (red circle) on Audacity, then press play on your cassette tape.

4) Press the stop button (yellow square) on Audacity when the tape is finished playing.

5) Use the "File -> Export as WAV" menu item to save your recording. The resulting WAV file can be saved on your computer, converted to MP3, or burned to a CD. Get fancy with Audacity's audio editor features: You can cut, paste and add effects easily.

You should record a ten-second clip at first, so you can play it back immediately in Audacity (green triangle button) and make sure your volume levels are right. If the recorded audio is too loud or has too much static, decrease the volume on your cassette player.

Don't stop with cassette tapes. The same technique can import, record and convert records / LPs / vinyl, 8-tracks, and other older audio formats. You may need a different cable to match your playback device, but the actual dubbing process is the same.

For those who haven't listened to themselves from twenty years ago, be careful, as what you hear may shock and surprise you. Dear sister, I'm sorry I hogged the tape recorder, slowly dictating "Elephant Eats the Profits", and refused to let you tape yourself talking to your parakeet. Childhood was rough.

Readers Respond

Bill has a few questions:

I recorded 2 albums totaling about 70 minutes. Recorded in 4 "sessions" - one per each side of vinyl. Did some editing (removing applause, etc). Filed as one "Project." The Audacity version played back just fine. After burning to CD, the CD has 382 files named b0001 thru b00549. Type AU Audio and most are 1049 kb in size, some are smaller. The CD is 100% full (I didn't think it should be, it's an 80-minute music CD-R).

Question 1: What did I do wrong?

Looks like you did the export wrong. Or rather, you saved the project, and saved those Audacity project files to the the CD.

When you create and save an Audacity project, you will get a single .AUP file, and a bunch of .AU files in a "_data" sub-directory. These are files meant specifically for Audacity. If you want to burn files to a CD, then you'll instead need to export your sound file.

While saving the Audacity project is fine, it's not what you want to use in recording to CD. Instead, create your project, and when you're ready to burn to CD, choose "Export as WAV" or "Export as MP3" from the File menu. Burn the resulting WAVs and MP3s to CD.

Question 2: How do I change the 23 recorded songs to 23 tracks on the CD? (They play 23 in a row in Audacity.)

The easiest way would be to do this:

1) Drag and select the part of the project that represents a single track.

2) From the File menu, choose "Export Selection as WAV" or "Export Selection as MP3".

Question 3: Can I remove scratches, pops, and clicks from my recorded sound file?

To some extent, yes. Use Audacity's "Noise Removal" tool, located in the Effect menu. By using noise removal, you can "teach" Audacity what sound is sound you want to keep, and what noise, static and pops you want to remove from your digital recording.

Arrow asks:

I have my hands on a very nice collection of 'oldies' on cassette and am trying to convert to audio CDs by transferring to my PC (via Audacity) and then to CD-R as WAV and MP3 files.

The AU files sound fine after recording. So do the WAV and MP3 files. However, when I burn a "Music CD" or "Audio CD" via Nero as I find that the recorded stuff is not playable (a) on my PC, (b) on my 5 year old CD deck, or (c) on my DVD/MP3 player.

What am I doing wrong ?

To start, I'd try doing two things:

1) Use different media. The fact that everything sounds okay until after you burn a music CD leads me to think your CD media might be defective, or possibly incompatible with your players. At the very least, you should be able to play the finished CDs on your computer. As you can't do that, see if different media helps.

2) Try creating a new music CD, but don't use Nero. Instead, use Microsoft's Windows Media Player. Start WMP, go to the File menu, choose "CDs and Devices", and choose "Burn Audio CD". You can drag-and-drop the files you want to burn into the "Burn List" area. Create a test CD in this way. Windows Media Player may not have an many burning options as Nero, but it will tell you where the problem lies: If the WMP burn works, there's a problem or incompatibility with the Nero software. If Windows Media Player doesn't burn the CD correctly, your issue could be a problem with media (see above) or a physical hardware problem (like a defective CD burner).

Brian asks:

Just wanted to say thanks for the great info on how to convert cassette to mp3. I have a question: How can I hear what I'm recording. I am using a regular boom box phone jack out to the mic on my laptop.

Assuming your laptop soundcard and speakers work, you'll be able to hear what you're recording. If, for example, you're using Audacity to record sound from your computer's microphone jack, the sound will play through the computer's speakers (or out of the soundcard speaker jack) as Audacity records. If you don't hear sound while recording, make sure the option is enabled in Audacity: In the "Edit -> Preferences" menu, under the "Audio I/O" tab, make sure "Software Playthrough" is checked.

Sheldon asks:

I followed your directions and was successful converting an audio cassette to a CD. However, I was only able to receive a monaural signal. I bought a stereo cable and connected from my boombox headphone to the line jack on my computer ( I also tried the microphone jack). When I tried to click on stereo I did not receive any incoming signal at all. Is this a function of my audio card and if so, is there a way of correcting this w/o purchasing a new soundcard? I am able to receive and play stereo downloads.

You have some options:

1) Verify that your boombox setup is indeed pushing out a stereo signal. If you have a female-female audio adapter, you can plug in a pair of headphones to the boombox's stereo cable. If you're not getting a stereo signal, then either the boombox isn't giving you stereo out the headphone jack, or the stereo cable isn't stereo, or is faulty. If you hear stereo, or don't have an appropriate adapter, read on.

2) By default, Audacity is set to record in mono. You have to tell it to tell Audacity to record a two-channel stereo signal: In the Edit menu, click Preferences, and verify the "Channels" dropdown is set to "2 (Stereo)." Then start your recording again.

3) It may be the fault of your sound card. Not knowing what sound card you have, I can't tell you if this is at fault or not. But if you can get the model number of your sound card, you can tell if 1) it supports stereo recording, and 2) you're plugging it into the right plug - the MIC input may be Mono, but the LIN input may be Stereo.

When I try to remove the tape hiss by clicking on the Effects button, I cannot get access to any of the tools, including noise removal.

Regarding the fact you can't use the Effect menu in Audacity: In order to have these menu options work, you have to tell Audacity to what part of your recording you want to apply the Effect. Either use the Edit menu -> Select -> All, or drag-and-select the section of audio to which you want to apply the effect. After doing either of these, the options in the Effect menu will be available.

Mrs. Yang asks:

Thank you for the information you posted on converting. I would like to ask if you have a rough idea how much space each 60-minute cassette would take. One of the sites says 1 minute = 1 MB. That sounds like a lot. Is that accurate according to you?

It depends on what you're doing with the recording afterwards. If you just want to record in low quality, and want to just store files on your computer for later listening, then the files can be very small, like .1 MB for every minute of audio. However, if you want to record in the proper stereo, high-quality format required by a CD player and CD-burning software, then yes, the resulting files will have a size of about 1 MB for every minute of audio.

Dave asks:

I'm using the software to copy cassettes to mp3. I'm not copying music, just recordings of speech. Quality does not need to be great so I would like to use my tape player high speed dubbing feature. This is important because I have hundreds of tapes to copy. How can I slow down the resulting mp3 recording?

It's easy with Audacity. First select the section of audio you want to slow down. In your case, you'll select the entire audio stream since you want to slow the whole thing down. (In the Edit menu, choose Select, then All.)

Then click the Effects menu, and choose Change Speed. You'll have to experiment (use the "Preview" tool) to find the right number to slow your recording, but once you find that number you can use it in the future for when you want to slow down tapes recorded at high speed.