A Brief Timeline of A Brief Timeline of Music FormatsMusic FormatsAudio Formats / Audio StorageAudio Formats / Audio Storage

Michael S. McDanielMichael S. McDaniel

AnalogAnalog vs. Digital vs. Digital

Analog is a Analog is a continuous wavecontinuous wave signal that signal that varies in frequency and/or amplitude. varies in frequency and/or amplitude.

Sound is naturally in this form. Sound is naturally in this form.

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Analog vs. Analog vs. DigitalDigital

Digital is a signal that is composed of Digital is a signal that is composed of pulses of zeroes and ones. pulses of zeroes and ones.

Which is Which?Which is Which?

AnalogAnalog DigitalDigital

Reel-to-ReelReel-to-Reel

Vinyl Record (LP) Vinyl Record (LP) 8-Track8-Track

CassetteCassette

CDCD

MP3MP3WMAWMA

FLACFLAC

DVD AudioDVD Audio

(1946 - ?) Reel-to-(1946 - ?) Reel-to-ReelReel

•Works like a cassette (magnetic tape is transferred from Works like a cassette (magnetic tape is transferred from one reel to the other)one reel to the other)

•Developed by Mullin, an audio engineer who was in WW2Developed by Mullin, an audio engineer who was in WW2

•Used extensively in music recordingUsed extensively in music recording

•Not portableNot portable

(1948 – ?) Vinyl (1948 – ?) Vinyl RecordRecord

•The primary technology The primary technology used for personal music used for personal music reproduction for most of the reproduction for most of the 20th century20th century

•A flat disk with a groove, A flat disk with a groove, played on a turntable by a played on a turntable by a needleneedle

•Came in different sizes Came in different sizes (speeds) – 45’s, 78’s, 33 1/3(speeds) – 45’s, 78’s, 33 1/3

•Not portableNot portable

•Still being produced todayStill being produced today

(1963 – ?) Cassette(1963 – ?) Cassette

•A contained reel-to-reel formatA contained reel-to-reel format

•Magnetic tape that goes across Magnetic tape that goes across a head that reads the signal a head that reads the signal

•Popular due to its size and portabilityPopular due to its size and portability

•Still being produced todayStill being produced today

(1964–1980) 8-Track (1964–1980) 8-Track TapeTape

•““Endless” reel-to-reel Endless” reel-to-reel cassettecassette

•Magnetic tape that Magnetic tape that goes across a head goes across a head that reads the signalthat reads the signal

•Popular from the Popular from the mid-60’s to the early mid-60’s to the early 80’s80’s

(1982 - ?) Compact (1982 - ?) Compact DiscDisc

•Digital Digital format!format!

•It is “optical media” : A laser burns dots into a plastic disk.It is “optical media” : A laser burns dots into a plastic disk.

•Those dots are either open or closed (1’s or 0’s)Those dots are either open or closed (1’s or 0’s)

•Most popular format used today.Most popular format used today.

•Very portable and inexpensive.Very portable and inexpensive.

Optical Disk Capacities Optical Disk Capacities vs. MP3 Playersvs. MP3 Players

0

5000

10000

15000

20000

25000

30000

MB

CD DVD iPod

MP3 PlayersMP3 Players

Mp3 Players like the iPod have taken Mp3 Players like the iPod have taken over.over.

They are much more easily accessibleThey are much more easily accessible

Available online through providers like Available online through providers like iTunes from AppleiTunes from Apple

THE PROBLEMTHE PROBLEM

The The RIAA (Recording Industry Association of America) has been making public the problem of copyright infringement prevalent among mp3 users.

Any Questions?Any Questions?