Music Mediums

1
Music Mediums

• Eric Aielli
• Carrie Haas
• Kassy

2
History of CD

• Based off laserdisc technology
• Phillips and Sony taskforce
• Sony Error Correction
• Phillips Servos and Lasers
• redbook standard
• Size was taken from cassette tape
• Introduced in 1983

3
Why make the CD?

• Solved problem of portability vs quality
• Tapes
• Portable, but have low quality sound
• Records
• High quality sound, not portable.
• CDs
• High quality sound and very portable

4
What other technologies made CDs possible?

• Phillips laser disc
• Materials
• microchips, plastics, lasers, etc..
• Decoding electronics
• Phillips had a 14bit D/A converter
• Sony had trick to convert it to 16bit,
  oversampling
• Cross interleaved Reed Solomon code (CIRC)
• Error correction and encoding by Sony

5
Positive Social Consequences

• Portable, high quality audio for the masses
• Last a long time 50-100 years
• Gave rise to digital audio

6
Bad Social Consequences

• Easy to lose
• Get scratched easily

7
What technologies were supplanted by this one?

• Pretty much all previous music reproduction
  technologies

8
Short term (25yr) future

• In 2008 the compact disc will be 25 years old
• Gave rise to many other formats

9
Long term future

• Will be replaced by other more portable digital
  formats