CD, DVD and Sound cards

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CD, DVD and Sound cards
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CD drives

• Overview
• optical drive laser shines on disc and
  transition from land to pit.
• pits and bumps less reflection (.12microns deep
  and .06 microns wide).
• spiral (3 miles long, over 2 billion pits)
• Types
• CD-ROM read only (metallic film with real
  pits)
• CD-R write once (heats the metal and dye
  together)
• CD-RW up to 1,000 times (alloy changes with
  heat)
• Capacities 650 and 700 MB
• Speeds 24 x 3,600 KBps, 52x 7,800 KBps

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DVD drives

• Overview
• also an optical drive
• higher capacity than CDs
• up to 133 minutes of video
• data capacity
• DVD-5, single-sided, single-layered, 4.7 GB
• DVD-9, single-sided, double-layered, 8.5 GB
• DVD-10, double-sided, single-layered, 9.4 GB
• DVD-18, double-sided, double-layered, 17 GB
• Types
• DVR-R - read only, 4.7 GB
• DVR-RW - 1,000 times, 4.7 GB, work in DVD players
• DVDRW - other format, becoming predominant
• DVDRW - both formats

DVD-RAM ?
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CD and DVD

• Interfaces
• EIDE (ATAPI)
• enable DMA in controller
• BIOS configuration, jumpers
• connect to sound card
• SATA, SCSI, USB
• Recording CDs and DVDs
• File systems
• ISO 9660 Level 1 - old, 8.3 format
• ISO 9660 Level 2 - file names up to 30
• Joliet - extension of ISO, up to 64, multisession
• Mount Rainer - in XP , drive needs to support

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CD and DVD

• Recording CDs and DVDs
• Windows vs. third-party
• Multisession writing - write in more than one
  session
• making data CDs/DVDs bootable
• Finalizing - closing the disc, can only be read
  after this
• buffer underrun recording CD/DVD faster than
  source
• remember the alphabet soup for media types
• More on burning CDs/DVDs
• New standard for DVDs
• HD DVD vs. Blu-ray
• Installing CDs/DVDs

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Sound cards

• Basic sound concepts
• What is sound? Measuring sounds decibel (dB)
• sampling rates and human hearing (20 Hz to 20
  kHz)
• digital audio DAC converters, PCM
• sampling rate signal measured many times per
  second
• sampling rate at least twice as the highest
  frequency
• 44.1 kHz CD quality
• 22.05 kHz radio quality
• 11.025 kHz telephone quality
• amplitude
• 8 bits 48 dB, 256 values for each sample
• 16 bits 96 dB (CDs use it), 64K values for
  each sample
• 24 bits 144 dB (pain threshold 125 dB), 16.8
  million values

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Sound cards

• Audio formats
• basic types aiff, au, wav, qt, ra, wma, mp3
• audio codec and audio compression lossy (111)
  and lossless (21).
• Uncompressed sound files size (1 minute)
• 44kHz 16 bits 10 MB
• 44kHz 24 bits 33 MB
• Compressed using MP3 4 minutes 4 MB (one
  song)
• Sound players
• Microsoft media player
• Real player
• QuickTime player

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Sound cards

• Sound card basics
• overview DAC, DSP, memory, ROM (wavetable), I/O
• specifications
• ISA or PCI cards 8, 16, 24 bits for each
  sampling
• voices multiple notes, from 32 to 64 voices
• FM and wavetable hardware and software support
• Total Harmonic Distortion (THD) , as low as
  .004
• Signal to Noise Ratio (SNR) in dB, cassette 60
  dB, CD 100dB
• Input and output connections CD, microphone,
  speaker(s), MIDI, S/PDIF, FireWire, USB, TAD
• Installing and upgrading
• a tutorial
• Sound cards future?
• X-Fi or motherboard