Using Audacity to Convert Analog Cassettes to MP3
Far more than simply an exercise in reclaiming my rather large tape collection (circa 1985), using Audacity to cut and clean your favorite yet no longer relevant 80s tunes (the majority of my collection) is an excellent exercise in learning the core features of what an enormously versatile and powerful tool Audacity can be for both personal and professional interests.
While hugely popular with the social media community for both its continually expanding professional features and its open source philosophy of development, this cross-platform digital audio editor allows for some fairly complex work using its multi-track editing capabilities and over 100+ pluginable filters and effects. It is, suffice it to say, more than ample for our needs.
Installation and Setup
So what are we going to need? The answer to this is partly why I have been getting more and more questions about converting their cassettes to digital format. Functional cassette decks are becoming increasingly hard to find not only because optical media (CDs, DVDs, and BDs) have completely replaced their popular use but also because it seems that mechanical playback devices are witnessing a decline as portable digital audio players (iPods and many newer mobile phones) are becoming increasing ubiquitous. The upshot is if you want to salvage some or all of your collection, the sooner, the better.
While installing Audacity is trivial, some get intimidated adding support for MP3 export (saving). Audacity uses LAME‘s MP3 encoder to handle this and for relatively obscure legal reasons cannot bundle it into its installation package. However, let’s make it as simple as possible1
- Download Audacity from their download page. As of this writing they are currently offering a stable (1.2) and beta version (1.3). This article is going to use the beta in that I prefer some of its newer features and have yet to have a problem with its functionality
- Install it with all of its defaults unless you have an opinion otherwise.
- Launch the app and follow the resulting dialog boxes (mainly asking your preferred language)
- From the Menu Bar select: Edit > Preferences > Import/Export
- In the section MP3 Export Library click on Download for the LAME MP3 Library, select the appropriate download based on your operating system
- Open the ZIP archive and copy and paste the lame_enc.dll to your Program FilesAudacityPlug-Ins folder
- Return now to your Audacity Import/Export settings and select Find Library under MP3 Export Library and browse back to Program FilesAudacityPlug-Ins
and select lame_enc.dll. Close out the dialogs with OK and that’s it.
Not really that bad. You are now ready to begin.
Setup and Import
Connect Cassette Deck to your Computer
Go ahead and use your 3.5mm stereo TRS miniture cable to connect your cassette deck headphone jack (you’ll likely need the 6.3mm stereo TRS adapter) to your computer’s sound card’s line-in (typically color coded blue).
Next you’ll want to be certain that Audacity is listening to this input source:
Edit > Preferences > Audio I/O > Recording > Device : Select Line-in from the drop-down menu and check that it is listening for 2 channels (stereo).
While you’re here, bump on down to the Quality section and check that your Default Sample Rate is at 44100 Hz at 16 bits. This is the standard sample rate and bit rate for an audio CD. Since our source material has far less quality, there is no sense going any higher nor would I advise going any lower.
Test that everything is working correctly. Play any old tape and press the Record button in Audacity. You should see a waveform scroll across the screen as Audacity captures the guilty pleasures of your youth.
Adjust for a Healthy Waveform
What we are looking for is a happy median where we are picking up enough of the softer elements of the song without pushing the louder elements over the maximum signal level that Audacity is able to capture, known as clipping.
The best way I’ve found to do this is to find a song that has a dramatic change from a peaceful soundscape to one that far more intense2. We’ll need to adjust both Audacity’s gain and the volume on the input source (our cassette deck) to be certain that we are getting a healthy waveform. What I did was set my Microphone level in the Mixer Toolbar to 0.2 and then adjusted my cassette deck’s volume till I was happy.
While this is a frustrating and potentially confusing process, keep in mind that this isn’t exactly a science. There is a fairly large margin of error given that many portable audio device managers have built-in normalization routines that will correct for most needs. I would recommend, however, that you run through this entire article with one or two songs and play them alongside MP3s that you’ve purchased to be certain they sound adequate3.
Once you’re feeling confident, then you’re over the worst of it. The rest of the process is largely procedural. Go ahead and capture the entire tape.4 Come back here when finished.
One thing you’re bound to notice listening to your tape tracks alongside something ripped directly from a CD is the inevitable ticks and grit inherit to any audio technology that requires actual physical contact with its media. If you’ve taken care of your tapes, likely it will not be that bad but, we are going to make it better nonetheless.
Audacity comes with a noise removal ‘effect’ right out of the box, so to speak. But before we use it, we need a clean sample of the noise inherent to the tape itself and any line noise that may exist. Thankfully, audio cassettes offer these between every song … but, we only need one. Select a just a few seconds from your complete master track, then Effect > Utility > Noise Removal > Noise Removal : Get Noise Profile under Step 1 of the Noise Removal dialog box. Now Audacity knows what to look for.
Now select the entire track and return once more to the noise removal effect dialog box. As you can see, this could get pretty complex if we knew what we were doing. Go ahead and experiment a bit with the settings but I recommend using the default settings unless you have a better opinion.5
Cutting and Export
Splitting the Source Track
Now that we’ve got our source track, it is now time for some manual labor. Play with your zoom tools to get a sense of the landscape of your source track. At anytime, go back to normal using View > Zoom Normal or Ctrl + 2. 6
Once you’re comfortable that you are able to see all the necessary detail for your track, place your cursor just in front of your first song. Use your keyboards forward and back arrows to make any adjustments. Now use your vertical scroll bar to move forward through your source track till you see the next song gap. This time hold down your Shift key and click your cursor down at the end of the song.7
Finally, were going to split our selection into a new track using the keyboard shortcut Ctrl + Alt + I. You’ll see a new track appear below. Repeat this process throughout the length of the source track. When you’re finished, your source track should only contain the remnants between the songs and whatever got recorded before the first song and after the last. Go ahead and delete this track by closing it. You should now have as many tracks as songs that are listed on the cassette case.
Tagging, and Export
Before we save these as individual MP3s, we need to name our tracks. In each of the track’s control areas (the left of the track) pop down the menu and select Name… Type in the song title here for each of the tracks.
Almost done. Modern music files, like any other digital file, has additional data surrounding it called metadata (data about data). Common metadata for most files includes author, creation date, modification date, etc. Music files, obvious have a lot more information associated with them: artist, album, genre, release date, etc. Digital music managers like iTunes and Winamp rely on these tags to properly categorize your music files. Before we attempt to export our files, we need to enter the basic details about this album so that our MP3s will play nice with your music manager.
Open Audacity Metadata Editor (File > Open Metadata Editor…) and complete the sections for Artist Name, Album Title, Year, and Genre. I also like to place a comment, “Digitized from analog cassette.” so that I can later seek out these files (for what reason, I don’t know).
At last, we are ready to export: File > Export Multiple… In the resulting dialog box change your export format to MP3 files, select a location to deposit your new MP3s, split files based on Tracks, and name files Using Label/Track Name. Finally, Export.
You’ll now be confronted with a series of Metadata Editor dialog boxes confirming the Track Title and Track Number fields, press OK for each and let Audacity get to work.
Programs such as MusicBrainz‘s Picard, Jaikoz, and MusicIP‘s MusicDNS take what amounts to an audio fingerprint of each of our files and attempts to match it against their database allowing you to not only supplement your existing metadata but also correct typos, genre choices, and refine release dates down to the month if not the day. They also add unique IDs that allow your music database to be correlated with larger databases allowing for some interesting applications to work on top of your collection.
Live albums tend not to have those handy gaps between songs and are usually filled with applause. My advise is to begin cutting each song from the end of the song and doing your Shift + Cursor Select at the beginning of the song. Additionally, since it is likely that you’ll be playing these songs apart from the album, those cuts in and out of the applause are going to be rather jolting. Use the Effect > Utility > Mixer > Cross Fade In/Out effects to soften these entrances and exits to songs. It makes for a little more work upfront but it definitely worth the time.
- Audacity Team: Transferring tapes and records to computer or CD
- Lifehacker: How to digitize cassette tapes
- For the purposes of this article I’ll assume the reader is a Window’s user, which I expect to be the majority of readers. Note, however that Audacity has detailed instructions that will guide you through installation for all platforms and versions. [↩]
- There is also a normalization plug-in available for Audacity though I have yet to experiment with it. I’d be interested in other’s experience with this feature [↩]
- Of course, they will never sound as good. But then, if you were a true audiophile, you would not even be reading this article [↩]
- If you have auto-reverse on your deck, all the better, otherwise, keep an eye on playback so that you can flip when need be. Also, don’t be afraid to fast forward past lame songs if you’ve got AMS functionality on your deck. [↩]
- If you do wish to tweak these settings, be certain you are using circumaural headphones in a quite setting so you can truly hear the noise. [↩]
- Usually I zoom out a couple of times before I start cutting to improve the speed at which I’m able to scroll but be careful that you don’t zoom out so far that you can’t see faint audio elements that sometime precede or follow a song. [↩]
- Note that when cutting a live/concert cassette, it is better to find the end first and vertically scroll to the beginning of the song. [↩]
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