Sound

1. Sound By John Sullivan For Multimedia I

2. Sound Contents • Sound • Digital Sound • Multimedia • The Web • Audio Software • Creating Music CDs

3. Sound How you use the power of sound can make the difference between an ordinary multimedia presentation and a professionally spectacular one. Sound is perhaps the most sensuous element in multimedia.

4. Sound continued Renowned Japanese film director, Akira Kurosawa, famous for his work in a visual medium, nonetheless has this to say about he medium “The most exciting moment is the moment when I add sound ….[Then] I tremble” (Alten, 1994, p.4.). A multimedia developer should be aware of sound at all times in order to successfully accomplish the information-conveying and aesthetic goals of a multimedia production (Tannenbaum, 1999).

5. Sound 3 For convenience, sound may be classified in three categories: • music • speech • other sounds Example: Laurie Smith Project 1

6. The Power of Sound Sounds vary in sound pressure level (amplitude) and in frequency or pitch. Amplitude refers to loudness of sound. Acoustics is the branch of physics that studies sound. • Sound pressure levels (loudness & volume) are measure in decibels (dB) • Decibels is a measurement on a logarithmic scale. When you make sound 100 times more intense, the increase in dB is not hundredfold, but only 20 dB.

7. When something vibrates in the air by moving back and forth (cone of a loudspeaker), it creates waves of pressure. Sound These waves spread like the ripples from a pebble tossed into a still pool and when they reach your eardrums, you experience the changes of pressure, or vibrations, as sound. The ripples propagate at about 750 mph, or Mach 1

8. Sound Frequency Range of frequencies from the low end of the spectrum (20hz to 40hz) to a high end of (20 Kilohertz)

9. Amplitude and Volume

10. Sound Intensities

11. Wave Forms Digitized

12. Analog to Digital • Digitization is the process involved in transforming an analog signal into a digital one. • Two steps • First analog must be sampled • Second is quantization • Quantization • Code- Word • Why? • Analog transformations introduce distortions and noise

13. Digital Sound • With digital sound you can edit, process, and retrieve sound data with more accuracy than analog. • Sampling rate - measured in samples per second • Sample size is the amount of information stored • The three most used sampling frequencies • Studio Quality – 88 kHz, 16 bit • CD Quality – 44.1 kHz, 22.05 kHz, 8 or 16 bit • Radio Quality – 22 kHz, 8 bit, mono • Telephone Quality – 11 kHz, 8 bit, mono

14. Sound Waves & Sampling - - - - - - - Higher sampling rate Low sampling rate

15. Sampling and File Size For Mono at the same sampling rate divide by 2

16. Audio Interchange File Format - AIFF, AIF Musical Instrument Digital Interface (MID, MDI, MFF) is an internationally accepted file format to store MIDI data Resource Interchange File Format (RIFF) developed by Microsoft and contains digital and MIDI MP3 – MPEG RA – Real Audio Sound (SND) - apple Roll (ROL) -developed by AdLib, Inc. for their sound cards Midi-like data and Yamaha FM synthesizer info Wave (Wav) - windows by Microsoft as subset of RIFF Sun Audio (AU) - Sun Microsystems Voice (V0C) Sound Blaster File Formats

17. Motion Picture Expert Group (MPEG) • MPEG – 1: intended for the storage of VCR-quality audio video sequences on CD-ROMs at 1.2 Mbps • MP3 music files are MPEG Audio Layer IIIstandard that is a digital audio compression algorithm that achieves a compression factor of about twelve while preserving sound quality. It does this by optimizing the compression according to the range of sound that people can actually hear. • MPEG – 2: targets studio quality television HDTV and multiple CD-quality audio channels at 4 to 6 Mbps • MPEG – 4: targets videoconferencing

18. MIDI Versus Digital Audio • Musical Instrument Digital Interface is a communications standard developed in the early 1980’s for electronic musical instruments. • MIDI data is a musical score not digitized sound • MIDI files are: • 200 to 1000 times smaller than CD-quality digital audio files. • Good for Web pages • In some cases, MIDI files sound better than digital audio files

19. Understanding MIDI • Controller - Musical instrument • 127 different instruments, 7 types of piano, 8 types of guitar, French horn, and 47 percussion sounds. • Synthesizer • Because MIDI systems do not record the actual sounds in the digital file, the resulting file is smaller. For example, on average 1 min of MIDI requires 30K whereas it would be 10.5 Meg for the same duration of CD-Quality digital audio (16 bit, 44 Khz, stereo) • Consistency in audio quality • Compatibility • Less processor speed

20. Midiscan

21. Choosing Between MIDI and Digital Audio • USE MIDI when • Digital audio won’t work because of space RAM, HD, CPU • You do not need spoken dialog • You have complete control of playback hardware • You have high-quality MIDI sound source • Use digital audio when • You have resources • You need spoken dialog

22. The Advantage of Digital Sound Systems • Advantages • No hiss • No loss of information • Easy access to recorded data • Synchronize sound with a high degree of accuracy. • Disadvantages • Sound accurate only if the MIDI playback device is identical to the device used in production • Cannot easily be used to play back spoken dialog.

23. You Need to Know • How to make sounds • How to record and edit sounds • How to incorporate sounds into your work

24. Editing Audio • Trimming - Do not just end or begin anywhere • Volume Adjustments • Format conversion • Fade-ins and fade-outs - enveloping • Resampling or down-sampling • Time Stretching • Reversing Sounds • Mixing audio - capability of mixing two or more audio files.

25. Music Stravinsky’s Rite of Spring • Music, the organized movement of sounds through a continuum of time. Music plays a role in all societies, and it exists in a large number of styles, each characteristic of a geographical region or a historical era. • Music has long been a significant part of religious ritual and pageants. • The purpose of the inclusion of music, as with any other medium, is to enhance the effectiveness of the communication.

26. Why Use Sound in a Multimedia Presentation? • Incorporate ambient sounds to reinforce your message • Add music to set the mood • Use sound to catch the interest (wake up) of the audience • Include narration effectively in training and educational applications

27. Sound and the Web • Used for • set mood • background sound • to draw attention - as message (newspaper dropping) • hover button sound • speech • Entertainment • Types of Sound Files • .au • .wav • .midi

28. Background Audio on the Web Internet Explorer bgsound The <bgsound> Tag <bgsound src=“audio/welcome.wav”> <bgsound src="Audio/w13mx11x8e.wav" loop=infinite> <head> <bgsound src="caribian.mid" loop=2> </head> Netscape embed <embed src=music.wav hidden autostart true loop=true> Whereas <embed src=music.wav> Might present audio control panel

29. Music Software • With Windows • Sound Recorder • With Sound Card • Turtle Beach Montego Bay

30. Winamp

31. HammerHead Rhythm Station

32. Sound Forge

33. GoldWave

34. Sonic Foundry Acid Music

35. PCDJ – Mixers

36. Napster - Packeteer Inc.

37. Napster Search

38. Napster Transfer

39. Adaptic 4.02d

40. CD Creator

41. Dragged files

42. Time Line Now Ready

43. CD Creation Setup

44. Once Done Labels by Default

45. Copyrights • Most developers play it safe by always making their own custom music from scratch in a sound studio, or with synthesizers • Others just take a risk and break the law • Educational Use • Fair Use • 10% or 30 seconds, which ever is shorter

46. References: Music Galore: http://www.geocities.com/Nashville/Opry/1809/ THX – sound Lucas Films PropellerHeads, Take California DecksandDrumandRockandRoll, Dreamworks Records, 1998 Microsoft Encarta, 1995 Jean Michel Jarre, First Rendez-vous, Renez-vous, Dreyfus, 1986 Laurie Smith, Project 1, 1999 Michelle Bzenk Project 3, 2000 www.sixflags.com HammerHead GoldWave

47. The End By John Sullivan