Digital Audio Assignment

Learning Activities, Part I:

Introduction to Digital Audio 

MP3 is considered the most popular music format, but has many drawbacks in comparison to other digital formats. Given that digital music is the future (if not the present) platform for listening and distribution, it is important to understand the differences between the myriad of choices.

Since many of you may already have some experience using iTunes, this assignment has been written for iTunes users. iTunes is available as a free download for both Mac and PC computers, and the software is installed on most of the Mac computers on main campus. The core information in this module, however, is applicable to all digital music programs; therefore, you may use any program you want to complete this assignment. All PCs come with Windows Media Player - a software which functions similarly to iTunes. And with a little digging, you will find that there is no shortage of free conversion, organization, and ripping software available for your use.

To get started, I would like for you to view this Apple tutorial on Digital Music Basics. You may find that the article is a little one sided when it comes to products, but the information contained within is still valid. Next, watch this short video on the basics of importing a CD (a process often referred to as "ripping a CD"). Then, review this brief summary of importing with iTunes. Finally, read these excerpts from the iTunes Help Section to learn the differences between various file formats, and how to select them when importing.

NOTE: If you launch iTunes and then insert a CD into your CD/DVD drive, iTunes will detect the CD, find the album and song information from an online database, and then present you with a list of import options. If you say OK and import the CD, the songs will be imported as AAC files. In the lower right corner of the window, you will see an Import CD button and an Import Settings button. You can use the Import Settings button to change the settings used to import the CD.   

By Thursday at 11:59 PM:

For the first part of your assignment, I would like to rip the same song from a CD using four different file formats:

1. an AAC file using iTunes default setting
2. an MP3 with the preset of Higher Quality (192kps)
3. an MP3 with the preset of Good Quality (128kps)
4. an AIFF file.
5. an MP3 created by stripping the audio from a YouTube video. Go to www.youtube-mp3.org and past the URL for your selected video into the field. Download the MP3. Drag it iTunes to import it.

When you import the song for the second time with different settings, you will be asked whether you want to replace the existing song...or not. Be sure to select Don’t Replace, as this option will enable you to retain all four copies. Once you have ripped the songs, open the Library view in iTunes. There you should see your song listed four times. Make note of the file size in MB (megabytes) for each of the four versions. To obtain file size info on a PC, right-click on the song and select Show in Windows Explorer. To accomplish the same on a Mac, highlight the song name and click ⌘-I on your keyboard for Get Info.  File size info should be housed under the tab for Summary.  Then within iTunes, I would like you to listen to each version, and jot down a few notes about the differences in quality between each version. You will find this task infinitely easier if you use the best audio system that you have access to, be it a high-end stereo, headphones, etc.

1. What are AAC, MP3, and AIFF?  How do they differ?
2. List the files sizes of the 4 different versions you ripped.
3. Could you hear any difference between the four files?  Explain these differences in greater detail.  How did the sound quality vary from one version to the next?
4. If you wanted to rip all of your CDs to your computer so that you could trade them in, what file format would you choose and why?