Explain Vinyl’s - How do they work?
- Disc with grooves cut into it, representing waveforms
- Each groove side is different stereo image representation
- Styles moves through grooves as disc is rotated
- vibrations converted to electrical signal
What are advantages of Vinyl’s?
- ## Warm sound
What are disadvantages of Vinyl’s?
- Sound quality deteriorates towards the centre of the record as the grooves are closer together
- Sound affected by scratches/dust
- Srone to rumble
- Not very portable
When were Cassettes launched?
1961 by Phillips
How do Cassettes work?
- Representation of audio signal transferred onto tape by rearranging magnetised particles of ferric oxide that are secured to its surface
- Playback head ‘reads’ magnetic signal and converts it to electrical signal for amplification
What are advantages of Cassette’s?
- Cheaper than Vinyl’s at the time
- Difficult to scratch or damage
- Easy to copy
- Longer recording times than LP’s
- More portable than Vinyl’s
What are disadvantages of Vinyl’s?
- Sometimes tangle and snap
- Need to clean recorders to avoid Oxide build up
- Quality degrades with each playing
- Susceptible to hiss
When were CD’s introduced?
1980’s
How do CD’s work?
Optical; they store data as pits which are read by a laser
Advantages of CD’s?
- Wider/more accurate frequency response
- Less noise
- Wider dynamic range
- No degradation
- Could use with computers
- Longer playing time
Disadvantages of CD’s?
- Scratching
- Some consider Brittle
- Less portable than digital
When were digital audio files introduced/prevalent?
1990’s
What is Lossy Audio Compression?
Reduces the file size by losing some frequency content and dynamic detail
- loses frequency detail and increases noise
What is Lossless Audio Compression?
Creates compressed files larger than lossy compression but does not lose any data
- maintain the original frequency content and level of noise
What are examples of lossy compression audio files?
MP3, AAC and WMA
What are examples of lossless compression audio files?
FLAC and ALAC
What are examples of uncompressed audio files?
WAV and AIF
