Audio File Formats

Wav, mp3, aif, aac, mp4... What are they? What's the difference between them?

Most people don't have to think about this topic, let alone these questions, but electronic musicians have to think about audio file formats every time they rip a CD to their hard drive, sync their iPod or phone, or play streaming audio over the internet. I'll explain each one of these file formats separately under three categories: "Uncompressed", "Lossless" and "Lossy".

UNCOMPRESSED AUDIO FORMATS

These two audio formats are what you would use if you want to preserve the highest quality of a digital recording. Neither one of these two formats compresses the audio in any way, but the tradeoff is a big file size: 9-10x bigger than and mp3 file size of the same song!

AIFF – short for Audio Interchange File Format (.aif), developed by Apple in 1988

WAV – short for Waveform Audio (.wav), developed by Microsoft in 1992.

LOSSLESS AUDIO FORMATS

Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data. The term lossless is in contrast to lossy data compression, which only allows an approximation of the original data to be reconstructed, in exchange for better compression rates.  Lossless compression also applies to digital images.

Apple Lossless - (.m4a) introduced by Apple Corporation in 1994.  What's the difference between AAC and M4A? Read this article.

LOSSY AUDIO FORMATS

Lossy compression is a data compression method which yields small file sizes, but from which the original data can never be totally reconstructed. Lossy compression will always results in generation loss: repeatedly compressing and decompressing a file will cause it to progressively lose quality. Lossy compression also applies to digital images.

MP3 - short for Motion Pictures Expert Group (MPEG-1) Audio Layer 3, developed in 1995

AAC - stands for Advanced Audio Coding
Pros: Designed to fix "serious performance flaws" in the MP3 format
Cons: some would view it as a proprietary format, only useable on iPods, iPhones, and other Apple Computer software, such as iTunes, but AAC files are compatible with Creative Zen Portable, Microsoft Zune, Sony PlayStation Portable (PSP), other portable media players, and mobile phones

WMA - stands for Windows Media Audio, developed by Microsoft in 1999

Three-Chord Guitar Songs

The final unit of Music Tech class is decidedly "non techy": it's learning how to play the guitar. Why? Many years ago the final unit was a songwriting unit using Garageband.  The students were encouraged to make their own song in Garageband using the loops that were provided.  The problem was that students stacked loops on top of each other that had conflicting chords.  How do I teach my students to hear chords? By teaching them to play chords on an acoustic guitar!

The goal of the guitar unit is to be able to play a simple three-chord song, even though during the course of the unit the students have learned five chords: G, C, D7, A7 and Em.  It reminds me of a (somewhat) famous Youtube sensation, Axis of Awesome's 4 Chord Song.  The idea is that if you know four basic chords: I, vi, IV, V (in G: G, Em, C, D) then you can play almost a thousand songs.

How many songs can you play with only three chords? Many, many, many!!

What three-chord song can you learn? Go search for "three chord songs" on Google or look through these three chord song lists for ideas:

Song Lists:

10 Famous Songs with Three Chords or Less via Guitartricks.com

3 Chord Songs: D A G via Chordie.com

Basics: 10 Famous Songs Using Only 3 Chords via UltimateGuitar.com

Top 30 Easy Guitar Chord Songs for Beginners via Guitarhabits.com

Chordie.com: Public Songbooks


Worship Songs via WorshipTogether.com:

Lord, I Need You (Chris Tomlin)

10,000 Reasons (Bless the Lord) via


Some websites will even help you with strumming patterns:

Brown-Eyed Girl (Van Morrison) via HeartwoodGuitar.com

Dance Project 1 (Block 3)

Click here to listen to my Dance Project 1.

1. Describe how to do project in simple steps for someone who wasn't in class with you.
2. Write about what new things you learned how to do in this project.
3. Write about problems you encountered and what you had to do to solve your problems.
4. Write down any questions you still have after completing the project.
5. Add at least one annotated screenshot of Audacity to your blog article to help explain what you wrote.

Screenshot of Audacity

Dance Project 1 (Block 2)

Click here to listen to my audio file of Dance Project 1.

1. Describe how to do project in simple steps for someone who wasn't in class with you.
2. Write about what new things you learned how to do in this project.
3. Write about problems you encountered and what you had to do to solve your problems.
4. Write down any questions you still have after completing the project.

How to Link from Google Drive to Your Blog

How to link your Dance Project 1 audio file to your blog:

1. Make a New folder in your Google Drive called "Music Tech" by pressing the red "new" button in the upper left corner. 
2. Upload your 39 second .mp3 file from your iMac to Google Drive>Music Tech by again going the red "new" button and pressing "File Upload"
3. Click once on the file you just uploaded to select it.



Share

4. Click on the Share button and select "Anyone with the link can view." 
5. Copy the link (Mac: Cmd-C)
6. Go back to your blog.
7. Type a sentence such as "Click here to listen to my shortened version of Dance Project 1."
8. Select that sentence with your mouse and click on the "Link" button in the Blogger menu bar.

Blogger Menu Bar

9. Paste in the link that you copied from Google Drive.  Click "Test this link" to make sure it works. Then press "OK"

URL = Uniform Resource Locator.  Most people call it a web address or a link.

10.  Go back to your blogger article and click the orange "Publish" button to see a live version of your newly created link to your song.  Click on the link to make sure it works and that anyone can listen to your song.

Press the orange "Publish" button to make your article live on the internet.

Now start typing about what you did and learned in Dance Project 1.  What should you write about?

1. Describe how to do project in simple steps for someone who wasn't in class with you.
2. Write about what new things you learned how to do in this project.
3. Write about problems you encountered and what you had to do to solve your problems.
4. Write down any questions you still have after completing the project.

WAV vs. MP3 as Explained to a Fifth Grader

I made this presentation to explain the difference between WAV and MP3 files.  I tried to make it simple enough that a fifth grader could understand it. I hope you enjoy my presentation!

Audio File Formats

Today I taught my Music Tech students how to embed a Google Slide presentation into their blogs.  It's a pretty simple procedure:

1. Go to Google Slides and find your presentation.
2. Click on File>Publish to Web in Google Slides.
3. Click on "Embed" and copy the embed code.
4. Go to Blogger and