MMTA Sound Cards 1

1
MMTA Sound Cards 1

• Original PC - simple speaker
• Change frequency and duration of square wave.
• Creative made the Sound Blaster
• 1st proper sound card industry standard.

2
MMTA Sound Cards 2

• Sound card functionality
• Music synthesis engine
• Digital effects engine
• 4 to 16-bit resolution
• sampling rates from 8 kHz to 48 kHz
• 16-bit processing
• full duplex support - simultaneous record and
  playback
• hardware accelerated support for games
• Direct Sound and Direct Sound 3D support
• 3D audio and surround sound

3
MMTA Sound Cards 3

• Two main features
• Digital Signal Processor
• A/D, D/A and synthesiser
• process multiple sounds, or channels,
  simultaneously
• Mixer
• mix input and output sources
• Also memory and interfaces

4
MMTA Sound Cards 4

• Sound sources
• Microphone
• Line Input ( e.g. from a record player / tuner)
• CD audio from CD-ROM drive
• Digitized sound from disk (e.g. .WAV files )
• Synthesis
• FM synthesis
• Wave-table synthesis

5
MMTA Sound Cards 5

• Outputs
• Line output
• Amplifier
• Digital output
• 3D effects
• Digital output .. record to disk

6
MMTA Sound Cards 6

• Interfaces
• CD-ROM
• Joystick
• MIDI
• S/PDIF, (Sony/Philips) - an ftp for audio data.
• Coaxial or optical connections.
• Plus firewire USB

7
MMTA Sound Cards 7

• FM cards vs. Wavetable cards
• Originally FM synthesis
• Create sound of instruments electronically
• Wavetable cards
• Manipulate digital recordings of real instruments
• instrument samples are stored in ROM
• Worst wavetable better than best synthesized
• Low cost cards store a few samples for each
  instrument and generate the rest electronically

8
MMTA Sound Cards 8

• The more samples stored, the better the quality
• Can download new samples to wavetable cards
• .WAV audio clips are not further processed by a
  sound card
• .MIDI files are significantly processed by the
  sound card

9
MMTA Sound Cards 9

• Creative - Xtreme Fidelity
• 16 to 24-bit A/D and D/A
• 8 to 96kHz sampling rate
• http//www.soundblaster.com/technology/
• Different sound options
• - games, leisure use or music creation
• Digital Signal Processor (DSP) with 51 million
  transistors
• Multiple processing engines for specific sound
  operations
• A 24-bit Crystallizer, which reverses some of the
  sound quality loss inherent in 16-bit

10
MMTA Sound Cards 10

• Creative - Xtreme Fidelity
• 16 to 24-bit A/D and D/A
• 8 to 96kHz sampling rate
• http//www.soundblaster.com/technology/
• Games are driving the industry
• See also Asus, Auzentech
• Consider home theatre 5.1 or 7.1 audio

11
MMTA Sound Cards 11

• Mobile phones
• Original sounds monophonic one note, fm
  synthesis.
• Tunes (just) recognisable small data files
• Polyphonic a number of notes played

12
MMTA Sound Cards 12

• RTTTL ring tone text transfer language
• SongTitle D4, O5, B1258c6,4a6,16g5
• DDuration 1full note, 21/2, 41/4 note etc.
• OOctave 5440Hz, 6880Hz, 71.76kHz etc.
• Bbeats per minute, followed by specific
  information