This document discusses digital audio media and production. It explains that all sound exists as analog waves that are sampled and converted to digital format for computer processing. Common digital audio formats are described, including uncompressed formats for high quality archiving and compressed formats like MP3 for distribution. Digital music software and services allow users to organize, playback, and distribute digital music collections on various devices. Suggestions are provided to improve an IT course by changing homework due dates and times.

1. DIGITAL AUDIO
MEDIA
By
John Amels, Camille Bauer-Lostaunau, Monica Suresh,
and Pawan Varyani

2. SAMPLING
 All sound in the natural
world exists in the form
of waves.
 These waves are
analog, or continuous.
 Computers do not
understand waves,
only 0’s and 1’s.
 Computers do this
through sampling.

3. SAMPLING CONT.
 Sampling is the analog to digital conversion of all
sound.
 The sound wave is cut into equal pieces known as
samples.
 Each sample is the same amount of time.
 The more samples per second (or sampling rate), the
higher the quality.
 The sample rate of a CD is 44,100.

4. DIGITAL AUDIO PRODUCTION
 Digital Audio Production is the process in which the
sounds from analog instruments gets recorded and
mixed into the music we listen to.
 While this was originally done all through analog
recording methods such as steel wire, tape, and
vinyl records, computers do most of the work today.

5. DIGITAL AUDIO PRODUCTION
CONT.
 Professional audio engineers use many different
types of technology.
 One of the most basic forms of audio production is a
voice recorder.
 More advanced technologies include mixing boards and
Digital Audio Workstations.
 A powerful tool that these engineers use is called a
Musical Instrument Digital Interface (MIDI).

6.  What?
 Portable device that plays and stores digital media
 Things to know:
 File formats supported
 Storage space
 Future:
 As wireless connection speeds increase, soon we’ll be
able to manage our collection in the clouds!

7.  What?
 An audio file that contains a broadcast
 Facts:
 Podcasting allows people to broadcast their message
to the world
 Available online, example: The Apple Store
 Distributed using RSS technology
 Allows for convenience

8. DIGITAL AUDIO FORMATS
 Why It Matters?
 If the user understands differences between file formats,
the users can properly pair digital music services with
the players, helps consumers get best quality
Facts:
Native formats often require lots of bandwidth transmit and
lots of computer storage, so digital audio compression was
developed.
Mp3 is the most recognized digital audio compression
format.

9. NON-COMPRESSED FORMAT
Why use non-compressed format?
Suitable for archiving and delivering sound at very
high resolutions.
Most accurate digital representation of sound wave.
Examples of non-compressed Format:
WAV, AIFF, and Broadcast WAV (BCW), MBWF,
Used throughout the digital audio life cycle, even
when they are not the target final format.

10. COMPRESSED FORMAT
Why compress?
To reduce file size  files will download faster, files
will stream over the Internet, more audio may be
stored in a given format
Varies in size and quality depending on:
Sample Rate, Bit depth, Number of channels, Choice
of Audio compression codec, and audio compression
codec settings
Examples of Compressed Formats:
i.e. Real audio, MP3, Dolby AC3 (DVD Video)

11. What is it?
Digital Music Software is used to obtain, manage, and
listen to digital music, and to encode music to various
audio formats.
(Definition from Emerge)
What can you do with it?
 Organize/play digital music, audio,
and video files
 Sort and arrange them by artist,
genre, song title, etc.
 Allows users to create a custom
playlists that can be transferred to
a CD, iPod, or any other portable
device
 Many popular media players (i.e.
iTunes) will provide a music
download service that users can add
to their music collections. (Emerge)

12. Continued…
With media software, you can sync music
with a portable digital music player
through the USB port.
You can either:
 Sync it manually
 Set it for automatic, so the next time you plug
your device in, it syncs.
(Emerge)

13. What is it?
Digital Music Distribution is the way music “gets around”.
(Emerge)
 CDs  Podcasts
 Online music services  Internet radio
(Rhapsody, Zune)  Satellite radio
 Cell phone music  HD radio
services

14. Continued…
Subscription:
 Satellite Radio: listener can listen to any to
the same channels from any location in range
 Napster and Rhapsody charge a monthly fee to
provide access to free access to millions of
songs/albums (emerge)
Download:
 iTunes/Amazon: download $0.99/song without
subscription to site
 Internet radio: similar to FM/AM radio except
its digitally delivered to your computer online
and more choices
 Wi-Fi radios: connect to internet using radio
(emerge)

15. SUGGESTED CHANGES TO IT 101
 Too many items of homework due on
the same day
 Homework's due at different times of
the day, example: 12am, as oppose to
during class, or before class

16. CITATIONS
 http://www.planetoftunes.com/digiaudio/daudiofiles.
html
 http://www.jiscdigitalmedia.ac.uk/audio/advice/unco
mpressed-audio-file-formats
 http://www.webopedia.com/DidYouKnow/Computer
_Science/2005/digital_audio_formats.asp
 Emerge