Introduction to Audio PDF

Introduction to Audio Prepared by Dr. Norshahila Ibrahim, FKMT 2024 [email protected]  Introduction to Audio OUTLINE 01 THE AUDIO 02 SOUND UNIT 03 HISTORY OF RECORDED AUDIO 04 ANALOG AND DIG...

Introduction to Audio Prepared by Dr. Norshahila Ibrahim, FKMT 2024 [email protected]  Introduction to Audio OUTLINE 01 THE AUDIO 02 SOUND UNIT 03 HISTORY OF RECORDED AUDIO 04 ANALOG AND DIGITAL SOUND 05 BASIC ELEMENTS OF SOUND DESIGN 2  Introduction to Audio LEARNING OBJECTIVES To understand the history of recorded To understand the audio and types of definition of audio and To explore the types of recorded audio. how to create the audio. sound design. 01 02 03 04 05 Provide an overview of To differentiate the the concept of digital analog and digital audio. sound. 3 WHAT IS AUDIO 4  Audio is a term used to describe any sound or noise in a range the human ear is capable of hearing. Music, voices, public address messages, what they all have in common is sound. Measured in Hertz, the audio signal on a computer is generated using a sound card and heard through speakers or headphones. THE The range of frequencies detectable by the human ear — approximately 20Hz to 20kHz. AUDIO 20Hz is the lowest-pitched (bassiest) sound we can hear, 20kHz is the highest pitch we can hear. 5 THE The black dots represent air molecules. As the loudspeaker vibrates, it causes the surrounding molecules to vibrate in a AUDIO particular pattern represented by the waveform. The vibrating air then causes the listener's eardrum to vibrate in the same pattern. The sound is a physical phenomenon that occurs when the vibrations of a transmitter body pass through a fluid or an elastic medium, and then they are perceived by the ear or any other receiver. An elastic medium can be air, water or solid materials such as iron, plastic or copper. 6  Three elements come into play in the phenomenon of sound: the transmitter, the transmission medium and the receiver. PRODUCE? HOW IT 7  The sound is generated when the vibration caused by PRODUCE? the emitter is propagated through a medium (air, water, etc) to end up reaching the receiver. It should be noted that sound can not propagate in a vacuum as light does: sound waves need a physical HOW IT medium in which they can travel from the transmitter to the receiver. A piano, a guitar, a speaker or a person’s vocal cords are examples of a sound source (the element that generates sound when vibrating). This vibration is transmitted to nearby air particles that also transmit it to the adjacent particles by an oscillating movement. This is how the sound wave propagates. 8 PRODUCE? To record a voice or music played outside a computer, an audio file is created using a microphone to record sound it detects. The sound is converted to a digital signal the HOW IT computer uses to create the audio file. Audio files can also be created using software running on a computer. For example, a person could use an audio program, like Audacity, to record the sound played in a video file. 9 Common File As mentioned above MP3 is the most Extension common audio file extension. However, there are other audio file extensions and types. and Types?.aif - AIF audio file.cda - CD audio track file.mid or.midi - MIDI audio file..mp3 - MP3 audio file.mpa - MPEG-2 audio file.ogg - Ogg Vorbis audio file.wav - WAV file.wma - WMA audio file.wpl - Windows Media Player playlist  A sound unit is any acoustic unit of sound measurement UNIT DESCRIPTION noise of sound measurement is called decibels (dB). Ratio of the sound dB decibel pressure to reference pressure to SOUND something a unit of perceived loudness equal to the loudness of a 1000-hertz tone at UNIT sone 40 dB above threshold, starting with 1 sone phon a unit of subjective loudness unit of sound frequency is called hertz Hz hertz (Hz) YOUR 11 LOGO SOUND WAVE SOUND WAVE PROPERTIES WAVELENGTH The distance between any point on a wave and the equivalent point on the next phase. Literally, the length of the wave. 14 SOUND WAVE PROPERTIES AMPLITUDE The strength or power of a wave signal. The "height" of a wave when viewed as a graph. Higher amplitudes are interpreted as a higher volume, hence the name "amplifier" for a device that increases amplitude. 15 SOUND WAVE PROPERTIES FREQUENCY The number of times the wavelength occurs in one second. Measured in kilohertz (Khz), or cycles per second. The faster the sound source vibrates, the higher the frequency. Higher frequencies are interpreted as a higher pitch. For example, when you sing in a high-pitched voice you are forcing your vocal chords to vibrate quickly. 16 SOUND WAVE FREQUENCY SPECTRUM 18 FREQUENCY SPECTRUM 19 WAVEFORM When the waveform is taller (that is, its top and The upper waveform represents the left bottom lie closer to +/- 1 so filling more of the vertical channel and the lower waveform represents space in the track), the audio is louder. When the top the right channel and bottom of the waveform lie closer to the zero line, the audio is quieter.  MONO SOUND VS STEREO SOUND YOUR 22 LOGO  MONO SOUND All audio information is combined into a single Mono, short for monaural, refers to a channel, and there is no distinction between single-channel audio reproduction system different sources or directions. where all the audio signals are mixed together and channeled through a single audio channel. Mono is often used in situations where spatial perception of audio is not crucial, such as early radio broadcasts or some public address systems. Represented as a single waveform when visualized on an audio editing software. YOUR 23 LOGO  STEREO SOUND Two separate audio channels allow for the Stereo, short for stereophonic, involves the placement of different sounds in the left and use of two independent audio channels to right speakers, creating a sense of depth and create a sense of directionality and spatial localization. distribution of sound. Stereo is widely used in music, movies, and multimedia to enhance the overall listening experience by simulating the way humans perceive sound in the real world. Represented as two waveforms (left and right channels) when visualized on an audio editing software. YOUR 24 LOGO  Key Differences Differences Mono Stereo Two independent audio channels Number of Channels One audio channel (left and right). Provides a sense of directionality and No spatial separation; all sounds are spatial distribution by utilizing Spatial Perception mixed and played through a single separate channels for different audio channel. elements. Used in situations where spatial Standard for music, movies, and perception is not critical, or for multimedia to create a more Common Usage compatibility with older audio immersive and realistic audio systems. experience. YOUR 25 LOGO HISTORY of RECORDED AUDIO 1857 Phonautograph The first device to record sound waves for visual study only as it did not have the capabilities to playback what was recorded. No sound = no fun 27 1878 Phonograph Perfected by “Mr. Light Bulb,” Thomas Edison (who also patented the first American motion picture camera). a cylinder covered with material that could be etched upon with a stylus. change in air pressure created by the sound caused the stylus to etch shallower or deeper grooves into the cylinder. play-back possible by tracing a needle through the grooves and amplifying the sound vibrations. difficulty in mass reproduction of recordings. 28 1887 Gramophone Much like a phonograph but used a flat disc instead of a round cylinder. Instead of depth etching as on the phonograph, sound-waves on the gramophone were etched with differing widths. Emile Berliner (inventor) called these discs “gramophone records” and Americans called them “phonograph records”. Although audio fidelity (quality) were fairly equivalent when comparing both phonograph cylinders and gramophone records, the disc records were easier and cheaper to mass-produce through a direct molding process. 29 1925 Electric Microphone Recording Process increased the flexibility of the process and the sound quality of the recordings made it possible to record one part (track) to a disc record, then play it back while simultaneously performing another part (track) and recording both parts (tracks) to a new disc record = first example of “over-dubbing and quazi-multitracking” 30 1930 Magnetic Tape involves the use of a magnetizable medium (tape), moving at a constant speed past a recording head sound waves are electrified through microphones and fed to the recording head inducing a pattern of magnetization upon the tape that is similar to the signal the ability to record and re-record audio with minimal loss in quality the ability to easily edit and rearrange recordings 31 1943 Multitrack Recordings the tape is divided into multiple tracks parallel with each other the induction of STEREO sound (although monophonic sound continued into the 1960s in many cases) ability to record two or more separate microphones simultaneously Les Paul’s experiments with tapes and recorders in the early 1950s led to the discovery of the ability to record separate elements of a musical piece at different times Paul was able to listen to tracks he already recorded while recording new parts in time alongside them = true “overdubbing” 32 3 Track Recorders popular in the 1950s through mid-1960s allowed two tracks to record stereo backing tracks, while the third track was reserved for the lead vocals (early Motown) 33 4 Track Recorders became the studio standard in the late 1960s (Beatles/Rolling Stones) Studio engineers began using two separate 4-track recorders to “bounce down” (transfer) multiple tracks recorded on the first machine to a single track on the second machine allowed 16 individual tracks to be “bounced” to 4 tracks on the second machine 34 Digital Recording developed in the 1970s using pulse-code modulation (PCM) PCM digitally represents sampled analog signals at uniform intervals that are quantized to the nearest value within a range of digital steps look at the picture to understand the jargon above 35 Digital Audio Tape (DAT) Sony 1987 much like a cassette tape but recorded digital audio at 16-bits instead of analog audio 36 Alesis Digital Audio Tape Recorders (ADAT) Alesis 1991 machine that uses VHS video tape to record 8-tracks of digit audio 37 Hard Disk Recorders with the introduction of the MP3 audio file format in the 1990s, music technology (and distribution) has developed at a tremendous rate music can be stored on and distributed through a personal computer with ease no more need of “tape” of any kind as the recorded music can now be saved as computer “memory” 38 39 TYPES of RECORDED AUDIO Stand alone Digital Audio Workstation (DAW) consoles 41 PC with recording software and a soundcard (i.e. Garage Band) 42 A combination of both (i.e. ProTools with interface like mBox or console) 43 WHERE AUDIO TECHNOLOGY is TODAY? WHERE AUDIO TECHNOLOGY IS TODAY? ELECTRONICS ARE GETTING AUDIO CONSOLE ARE MORE EFFICIENT SMALLER Gone are the days of seeing racks on racks of As seen in consumer electronics, technology amplifiers on stage. In the past, an Audio has advanced to needing smaller Engineer required many racks of amplifiers for components, are made with lighter materials a show, as each one was capable of only and have immensely more capabilities producing so much power. Audio Engineers compared to analog counterparts. can now fit the same amount of power into a smaller footprint, as amplifiers have got lighter Analog consoles did not have all the onboard and more powerful. This effectively reduces processing, effects units. The advent of digital the quantity or size of the electronics needed consoles brought on the ability to put much to reproduce an amplified signal. more into a single device. 45  WHERE AUDIO TECHNOLOGY IS TODAY? DIGITAL AUDIO-TRANSPORT NETWORK CONTROL IN THE PALM TECHNOLOGY CONTINUES TO GROW OF HAND Digital audio can now be carried over a network using audio Modern technology now allows everyone to have a over Ethernet, audio over IP or other streaming media computer in their pocket. As we see in Smartphones, standards and systems. Digital audio can be carried over technology is getting smaller but the screens are digital audio interfaces, such as Dante (delivering ultra-low getting bigger. There is a demand for them to do more latency and near-perfect synchronization), AES3 (also and more with the ease of just adding an app. This known as AES/EBU, this was jointly developed by the Audio provides the Audio Engineer with the capability to tune Engineering Society (AES) and the European Broadcasting the PA and make adjustments right from a Smartphone Union EBU) or MADI (Multichannel Audio Digital Interface). or tablet, giving them the flexibility to assess the sound quality anywhere in the room and not have to run back Several interfaces are engineered to carry digital video and to the console to make adjustments. audio together, including HDMI and DisplayPort. Dante 46  Introduction to Audio NEXT EVOLUTION OF AUDIO? 01 02 03 COST WIRELESS LIGHTER, REDUCTIONS SMALLER & TECHNOLOGY as new technologies are Continuing wireless POWERFUL developed so that the technology improvements reduce the costs advancements can be put and reliability to reduce the associated with the into action on the stages, amount of cabling and storage, shipping and floors, trusses, and towers connectivity that is currently setup time for large of the events of tomorrow. required. audio systems. Passive Audio Auto play, for example background music that starts as soon as loads. https://www.youtube.com/watch?v=oW kHQQpzuF8&ab_channel=APerfectCircle -Topic Active Audio Used during the game as soon as something like a ’Start’ button is press. Dynamic Audio Sound which reacts to changes in the gameplay environment or in response to a user Examples : Score point in games Adaptive Audio Audio respond to an event that the player triggers. When doing a challenge with a time constraint, as the time runs out the tempo gets faster. Examples : Warning sound Diegetic Diegetic sound is any sound that come out from the storyworld of the film. Sounds The source of diegetic sound doesn't necessarily need to be seen on screen, as long as the audience understands that it is coming from something within the film. 3 Examples of Diegetic Sound 1. Character dialogue is the clearest example of diegetic sound. 2. Object sounds make a film more realistic. 3. Music emanating from within in the film helps the audience become absorbed in a scene. Non-diegetic Non-diegetic sound is any sound that does not originate from within the film’s world. sound The film’s characters are not able to hear non-diegetic sound. All non-diegetic sound is commentary or nonliteral sound added by sound editors in post-production. 3 Examples of Non-Diegetic Sound 1. The film’s musical score is used to set the film’s tone, manipulate emotions, add drama, express ambiguity, or provide an element of surprise. 2. Sound effects are added for dramatic effect. For example, a record scratch sound added for comic relief is not heard by the characters in the film. 3. Narration or voice over is used to help explain or reinforce the plot.  Introduction to Audio BASICS ELEMENTS OF SOUND DESIGN 01 02 03 04 05 FOLEY AUDIO VOICE AMBIANCE MUSIC SOUND EFFECTS OVER Nature Real Imagine & Narrator Feel Recreated 54  Introduction to Audio AMBIANCE essentially background noise needs to inform and be descriptive without being overwhelming or distracting the viewer from the story should inform the viewer about where the action is taking place For example, if we are viewing a scene in a forest what are we likely to hear? Birds tweeting in the distance and winds It serves as one tool which can gently blowing would match our allow us to become more fully experience of spending time in woods. immersed in the story or scene as it unfolds before us https://www.youtube.com/watch?v=u99Rp1knyLQ&ab_channel=Ms%26MrRight 56 https://www.youtube.com/watch?v=gOd4PTY3KKw&t=67s&ab_channel=AlexTomeo 57 https://www.youtube.com/watch?v=o1yBIOtxP5o&ab_channel=xGUANOLOCOx 58  Introduction to Audio FOLEY SOUND 1 These are the sounds that make the scene seem more real to us. For example, when a character walks they are not 2 silent. We mare hear the gentle swish-swish of their clothing as they move or the sound of their footsteps on the concrete These are sounds that make us more 3 readily enter the world we are faced with. 4 They are also sounds that can be easily recorded with a real microphone. Foley sounds also feature in a feature 5 film in addition to animation and motion design. 59 https://www.youtube.com/watch?v=7GGC6zpF-Qs&ab_channel=LaurenSamways 60 https://www.youtube.com/watch?v=UO3N_PRIgX0&ab_channel=GreatBigStory 61  Introduction to Audio AUDIO EFFECTS These are sounds that For example, the are not naturally sound of a battle in created in the real outer space is not world and therefore something that can be can’t be recorded by recorded but must be means of a imagines and microphone. recreated. 62 https://www.youtube.com/watch?v=5q3qb5K_kv4&ab_channel=DuncanSoo 63  Introduction to Audio VOICE OVER 1 2 It is the narrator's voice Self-explanatory which guides us through what is happening on the screen. 3 4 In the film, we rarely see the Similarly in motion design, narrator. For example, in 500 although sometimes in Days of Summer, we never explainer videos we can be see the narrator, but he plays guided through the scene by a pivotal role in guiding us a character who also is the through the film and narrator of the piece. highlighting key moments. 64 https://www.youtube.com/watch?v=xqAgvTP-UDc&t=89s&ab_channel=Georgina9703 65 https://www.youtube.com/watch?v=5VhAQsCNBrI&ab_channel=evermotivated 66  Introduction to Audio MUSIC Music is a tool we can use to set the dynamics of mood we wish to convey through the motion design piece. What mood do we want our experience while watching the story? This should be the first question we ask when designing the scene and also when choosing music to amplify the art. https://www.youtube.com/watch?v=TcMBFSGVi1c&ab_channel=MarvelEntertainment 68 https://www.youtube.com/watch?v=6mCKnsP33Lg&ab_channel=SantoshGhimire 69 REMEMBER! Not every motion piece will need all five elements. Sometimes you will only BLEND… need a voice over, and music or sound effects. Balance is important when it comes to sound design. All the audio level of each layer needs to be adjusted and balanced to create the right effect.  Introduction to Audio CAREERS in AUDIO 71 CREATE AMBIENCE SOUND INDIVIDUAL ASSIGNMENT Use any audio device Record 2 types of ambience sounds (at least 1 minute/sound) Record the process (BTS) Overall duration: not more than 5 minutes Upload on Youtube – share the link Ref: https://www.youtube.com/watch?v=EBEyM u401UM&t=96s&ab_channel=SkibbyProductio n THANK YOU MUCH!  Introduction to Audio ANALOG vs DIGITAL VS ANALOG DIGITAL An analog audio signal is an electronic copy of an Digital audio is a representation of sound recorded original audio signal as found in nature. Any sound in, or converted into, digital form. In digital audio, reproduction procedure for a real acoustic event the sound wave of the audio signal is typically starts with analog (the event) and ends. encoded as numerical samples in a continuous sequence. 74 ANALOG vs DIGITAL Definition Sources Quality Wave design Adv Disadv … …  Introduction to Audio ANALOG: Adv vs Disadv 76  Introduction to Audio ANALOG: Adv vs Disadv 77  Introduction to Audio ANALOG: Adv vs Disadv 78 Basic Elements of Sound Design GROUP ASSIGNMENT Basic Elements of Sound Design GROUP ASSIGNMENT Go to Muzium Pendidikan Nasional UPSI. Select 3 rooms. Use own creativity, create a background music for feel and emotions of the surrounding of the room. Combine all basic elements of sound design (ambiance, foley, audio effects, and music). without voice over. Record the process (BTS). Overall duration: 3-4 minutes/room. Upload on Youtube – share the link on MyGuru.