Transcript A Brief Timeline of Music Formats

A Brief Timeline of
Music Formats
Audio Formats / Audio Storage
Michael S. McDaniel
Analog vs. Digital
 Analog is a continuous wave signal that
varies in frequency and/or amplitude.
 Sound is naturally in this form.
f ( x)  sin x
Analog vs. Digital
 Digital is a signal that is composed of
pulses of zeroes and ones.
Which is Which?
Analog
Digital
Reel-to-Reel
Vinyl Record (LP)
8-Track
Cassette
CD
MP3
WMA
FLAC
DVD Audio
(1946 - ?)
Reel-to-Reel
•Works like a cassette (magnetic tape is transferred from
one reel to the other)
•Developed by Mullin, an audio engineer who was in WW2
•Used extensively in music recording
•Not portable
(1948 – ?)
Vinyl Record
•The primary technology
used for personal music
reproduction for most of the
20th century
•A flat disk with a groove,
played on a turntable by a
needle
•Came in different sizes
(speeds) – 45’s, 78’s, 33 1/3
•Not portable
•Still being produced today
(1963 – ?)
Cassette
•A contained reel-to-reel format
•Magnetic tape that goes across
a head that reads the signal
•Popular due to its size and portability
•Still being produced today
(1964–1980) 8-Track Tape
•“Endless” reel-to-reel
cassette
•Magnetic tape that
goes across a head
that reads the signal
•Popular from the
mid-60’s to the early
80’s
(1982 - ?)
Compact Disc
•Digital format!
•It is “optical media” : A laser burns dots into a plastic disk.
•Those dots are either open or closed (1’s or 0’s)
•Most popular format used today.
•Very portable and inexpensive.
Optical Disk Capacities
vs. MP3 Players
30000
25000
20000
15000
MB
10000
5000
0
CD
DVD
iPod
MP3 Players
Mp3 Players like the iPod have taken
over.
They are much more easily accessible
Available online through providers like
iTunes from Apple
THE PROBLEM
The RIAA (Recording Industry Association of America)
has been making public the problem of copyright
infringement prevalent among mp3 users.
Any Questions?