Audio Hardware & Software PDF

− DGV1013 − AUDIO HARDWARE & SOFTWARE Prepared by Dr. Norshahila Ibrahim [email protected]  Revision – Introduction to Audio ANALOG vs DIGITAL VS ANALOG...

− DGV1013 − AUDIO HARDWARE & SOFTWARE Prepared by Dr. Norshahila Ibrahim [email protected]  Revision – Introduction to Audio ANALOG vs DIGITAL VS ANALOG DIGITAL An analog audio signal is an Digital audio is a representation of electronic copy of an original audio sound recorded in, or converted signal as found in nature. Any sound into, digital form. In digital audio, the reproduction procedure for a real sound wave of the audio signal is acoustic event starts with analog (the typically encoded as numerical event) and ends. samples in a continuous sequence. 2  Revision – Introduction to Audio ANALOG VS DIGITAL ANALOG vs DIGITAL Analog is an electronic copy of an original sound recorded in, or converted into digital audio signal Definition form non-continuous electrical signals (discrete continuous electrical signals Signal time signals) Nature, temperature, light, pressure Sources Electrical instruments To get better quality, the sound Better, accurate, smoother Quality should be edit Sine waves Wave design Square waves Used in analog devices only. Best suited Best suited for Computing and digital for audio and video transmission. Uses electronics. Stored in the form of Wave signal Memory Stored in the form of binary bit Cheaper, more less Cost Expensive, high 3  Introduction to Audio ANALOG VS DIGITAL 4  Introduction to Audio ANALOG VS DIGITAL 5  Introduction to Audio ANALOG VS DIGITAL 6 OUTLINE 1 LEARNING OBJECTIVES 2 HARDWARE FOR AUDIO RECORDING TOPIC 3 SOFTWARE FOR AUDIO RECORDING 4 CLASS ACTIVITY - TEACH YOUR BUDDIES  Audio Hardware & Software LEARNING OBJECTIVES 1 To introduce the concept of recording and storing audio. 2 To introduce the hardware related to audio recording. 3 To explain the concept of free and open source software solutions for audio production. 4 To analyze the pros and cons of free software in audio production. 5 To list available software for audio recording, editing and mixing. 8 HARDWARE FOR AUDIO RECORDING 1. Microphone 2. Audio recorder 3. Headphones 4. Audio mixer 5. Computer MICROPHONE S A Microphone is basically a transducer that converts sound waves into electrical waves. The electrical waves can then be either amplified using loudspeakers, or recorded and stored. Microphones are either built-in—as in computers, telephones, or mobile phones—or free-standing devices, like those you use in an auditorium or in a studio. They come in various sizes and shapes. MICROPHONES - TIPS Key Considerations while selecting microphones before purchasing or hiring a microphone, one would do well to consider the following five factors.  1. IMPEDANCE means resistance offered to the flow of the electrical audio signal. You may have noticed that big A microphone with low audio players that come with a impedance can be used with a microphone (for karaoke) have a long cable, since the signal very short cable. This is because strength that emerges will still be they have very high impedance, quite strong. that is, they offer high resistance to the flow of the signal to the recorder. Most professional microphones are of low impedance, making If the cable is very long, the signal them best suited for audio that reaches the recording device recording. would be too weak for any practical purpose. Impedance is measured in ohms. Professional microphones have Low impedance is better than an impedance of 200 ohms or high impedance. lower. 2. FREQUENCY RESPONCE This is a microphone’s capability to receive high and low sounds. A good, professional microphone can receive frequencies ranging from 20 to 25,000 Hz. 3. PICKUP PATTERN How a microphone picks up sound directionally and its sensitivity to sound based on how the microphone is oriented. Situations may demand requirement of a producer to record sound either from one direction, two directions or all directions. Situations may also require the producer to actively reject sounds from other directions while picking up sounds clearly from one. There are different microphones that meet these requirements. 3. PICKUP PATTERN 4 major pickup patterns need encounter in the microphone world, and in which situations you'll want to use them. Omnidirectional Studio environments where capturing a sound in a "space" is desired. Highly controlled live sound situations, especially when looking for a clear, natural, open sound without wind or breath pops/noise, or coloration of sounds not directly in front of the microphone (off-axis). 3. PICKUP PATTERN 4 major pickup patterns need encounter in the microphone world, and in which situations you'll want to use them. Bidirectional Studio environments where capturing two sources with less "bleed" than an omni is required Situations where extreme rejection is needed (i.e., mic'ing a singer who plays guitar simultaneously in a recording). A necessary pickup pattern for Mid-Side or Blumlein mic'ing techniques. 3. PICKUP PATTERN 4 major pickup patterns need encounter in the microphone world, and in which situations you'll want to use them. Cardioid An all-around "workhorse" pattern for the stage and studio. Close placement in live and studio situations to isolate sound source from surrounding sources Live vocal mics to help eliminate "bleed" on stage. 3. PICKUP PATTERN 4 major pickup patterns need encounter in the microphone world, and in which situations you'll want to use them. Hypercardioid or Supercardioid Capturing sound in a live environment where a more isolated sound is required Live vocal mics to help eliminate even more "bleed" onstage than a cardioid mic Studio situations and live recordings that need a highly directional and focused sound 4. BALANCED & UNBALANCED MICROPHONES Balanced microphones are best used for professional recording purposes. Handling Noise. An unbalanced connection uses 2 wires: one +ve and one ground cable. On the other hand, a balanced connection uses 3 wires. One +ve, one –ve and one ground cable. The shield is connected to the ground and protects the signals from external electromagnetic interference. This makes the system more immune to noise from poor electrical wiring in a room, computers, etc. With an unbalanced microphone, one of the signal wires is the shield and the other is the positive signal. Any noise picked up on the shield will be fed directly into the amplifier or mixer input. 4. BALANCED & UNBALANCED MICROPHONES 4. BALANCED & UNBALANCED MICROPHONES MORE REFERENCE: https://www.youtube.com/watch?v=3NONoES76og&ab_channel=Q uanta 5. SENSITIVITY The ability of a microphone to pick up very faint sounds is termed as its sensitivity. High-sensitivity microphones are normally used in studios and low-sensitivity microphones on the field, where the chances of the microphone moving or being hit by strong wind are greater.  Audio Hardware & Software TAKING CARE MICROPHONE UNIT Do not tap or blow into any microphone to test it. Switch off the microphones after use, if they have Just talk. in-built off/on switches. This is especially important for battery powered condensor microphones. Keep microphones in their pouches when not in use. Use high-quality connectors and cables for microphones. Keep microphones away from moisture, water and fire, as well as physical shocks of any kind. Do not leave heavy microphones dangling from a cable. Do not swing them holding the cable Do not pull out a connector holding the cable. either. Always grasp the connector (jack) to disconnect. Do not use any liquid whatsoever to clean Remove the batteries if not in use. Replace them microphones. with new but similar type batteries periodically. 23 AUDIO RECORDER An audio recorder is a device that records the electrical signals emerging from a microphone as audio files. These audio files can then be electronically moved from one device to another (for instance, a computer) and edited. There are several types of audio recorders in the market: some easy to use, some economical and some that combine both these characteristics in addition to being robust.  Audio recorders are devices that can receive an audio signal from a microphone input and store them in a recording medium. Audio recorders can be use in the studio or in the field. The OLD VERSION - included cassette recorders, and reel-to-reel spool tape recorders, both of which record on magnetic tape. The NEW VERSION - digital and record on digital media like secure digital (SD) or compact flash (CF) cards, or hard disks. Portable field audio recorders usually come with built-in microphones good enough to record broadcast grade audio. AUDIO Some of them even come with wind filters, and record on easily available and reusable digital media. RECORDER Come with variety of size, price and types. You may have noticed that you can record on a slightly high-end mobile phone too. 25  Audio Hardware & Software CHECKLIST PURCHASING DIGITAL AUDIO RECORDER Recording format: Should be able to record in Should have built-in speakers.WAV format, 16/24 bit. It is better if it can also record ‘mp3’ format at varying bit rates. Should have a media card slot with a capacity for high data storage (2 GB or more) Should have built-in stereo microphones, preferably covered with a wind shield Some recorders are capable of recording from a landline telephone cable. Some can also be Should have a provision to connect headphones connected to a computer and used as a to monitor audio microphone to record directly into the computer using an audio software. Should have adjustable controls for input audio levels Some recorders come with built-in batteries that can be charged. Others accept consumer grade Should have a USB cable and connector slot to batteries of AA or AAA type. enable import of audio files to a computer 26 HEADPHONES Headphones are devices that are used to listen to the audio signal being played back by a playback device. In some ways, they are comparable to a small pair of speakers mounted on a band that can be worn over the head. Headphones are also useful when you want to listen to audio without disturbing others around you. In-ear Headphones On-ear Headphones Over-ear Headphones  Audio Hardware & Software EAR BUD HEADPHONES Earbuds or In-ear or Earphones These are probably the most common 1 types of headphones, as they are used with all kinds of portable music players and mobile phones. Also called earphones, they are often 2 provided as free accessories with these devices. While some low-quality ear bud 3 headphones fit loosely within the external ear, there are some that fit into the ear canal itself. While earphones are good for listening 4 to music, they are best avoided to monitor audio while recording. 29  Audio Hardware & Software ON-EAR HEADPHONES Sit on the ears 1 usually a bit smaller and lighter than over-the-ear models. tend to have foam or sometimes leatherette 2 pads for extra comfort, and usually have adjustable headbands for a snug fit. don’t cover the ears, ambient noise tends 3 to enter the ears, making it difficult to monitor audio in critical conditions. best used in office situations, for simple 4 listening purposes, or for conducting voice chats over the Internet. 31  Audio Hardware & Software OVER-THE-EAR HEADPHONES 1 traditional-looking headphones, with cushioned pads that enclose and cover the whole ear more comfortable to wear over long periods, 2 and they generally deliver good sound quality 3 best suited for audio monitoring purposes in the studio as well as in the field. Some varieties also cancel out noise, making 4 it easier for the producer/technical personnel to monitor audio. 32 AUDIO MIXER An audio mixer is a device that helps connect multiple audio sources to a recorder, while also helping you to refine and improve the quality of the sound. Mixers are often used to individually control the sound from each source independently, in order to achieve a good balance between the various sources. AUDIO MIXERS: FUNCTIONS Control the volume of Combine and balance the signals inputs Coming from various inputs Coming from various sources, by sliding (microphones, audio players, etc.) the faders up and down. For example, in using faders. The faders help in an audio mixer with six inputs, you regulating the input levels of connect six microphones to record a sound coming from various musical score. Controlling each source sources. by way of its dedicated fader helps one in balancing the input of each instrument, so that we make the combined output pleasant to hear. 34 AUDIO MIXERS: FUNCTIONS Equalize the audio Auxiliary Send (“Aux Send”) EQ stands for Equalization. Manipulate Used to send the output to other the frequency characteristics of the external devices like an effects input sound. Equalizing involves generator. The output from the controlling the audio signal by Aux Send is again taken back into increasing some wanted frequencies the audio mixer, mixed and routed and decreasing the unwanted ones. For through the final output. example, you can reduce hiss in speech by equalizing the input. 35 AUDIO MIXERS: FUNCTIONS Route the mixed and Enable monitoring equalized audio signals to a specific output (a of all the functions mentioned recorder/speaker/headphone). above through speakers/headphones as they are being recorded/broadcast. 36  Audio Hardware & Software AUDIO MIXERS FEATURES Can take in any number of audio inputs Provide balanced outputs to connect to a from 2 to 6 recorder If you have to work with portable audio mixers, ensure the following: Provide phantom power for condenser microphones It has enough audio inputs. Gain and level controls It has a warning signal for signal overloads. Monitor headphones Don’t mix or overlap audio and power cables. Keep them as far as possible from Can be low cut filters by cutting out low each other. frequencies while recording outdoors Can act as limiters by preventing distortion of audio even when it is very high 37 COMPUTER For the purposes of audio recording and editing, the computers we use are called Digital Audio Workstations (DAWs). They are different from the computers we use for day-to-day office work and Internet browsing in that they are more powerful; and also have a variety of audio inputs and outputs. Most will also have a sound card, which is a device that can convert analogue audio to digital audio, and vice versa. Some may be designed to work with specific hardware that can be connected to them to record and edit audio files. Audio Hardware & Software SOUND CARDS SOUND CARDS A sound card is a peripheral that is connected to a computer. It is sometimes also called a sound board or an audio card. Most computers come with some form of a basic sound card to edit and playback audio. If your computer has inputs for a microphone and a headphone on the back of the CPU (Central Processing Unit), which is the box that houses your computer’s hardware, your computer has a sound card. It must be noted that while some cards only playback audio, duplex sound cards enable simultaneous input and output of audio, and also enable audio recording. Some of the motherboards used in computers have good sound cards that are integrated into the motherboards themselves. 39 SOFTWARE FOR AUDIO RECORDING 1. Audacity 2. Ardour 3. JAMin 4. Tenacity FREE and OPEN SOURCE SOFTWARE? GENERAL INFORMATION The free and open source software movement heralded a new era of knowledge building society—one which was non-hierarchical, adhering to the principles of equal access, freedom to use, adapt, modify and redistribute. Both the terms, though quite often used interchangeably, are not really synonyms. Both the terms are underpinned by a similar value structure, even though they are different in their philosophical approaches. The Free Software Foundation has been promoting the term Free Software The Open Source Initiative has been using the term Open Source Software. 41  01 FREEDOM 1 The freedom to run the program for any purpose. to confirm in order to qualify as free FREEDOM 02 LEVEL OF FREEDOM 2 The freedom to study how the program works, and change it in order to make it do what you wish. 03 FREEDOM 3 The freedom to redistribute copies so you can help your family/friends/neighbours/colleagues. software 04 FREEDOM 4 The freedom to improve the program, and release your improvements (and modified versions in general) to the public, so that the community benefits as a whole. 42 Open Source 01 FREEDOM Software to use and share the software FREEDOM Why? 02 to modify and adapt the software to their unique situations FREE SUPPORT 03 from the global community, which is often seen as far superior to the paid support by a company providing a proprietary software COST 04 effectiveness Audio Hardware & Software AUDACITY Audacity is one of the most commonly used audio recording and editing software. It is a non-linear, multi-track and feature-rich editing system that works on Windows, Mac or Linux platforms. Recording live audio Converting magnetic tape recordings and LP records into digital recordings or CDs Editing Ogg Vorbis, MP3, WAV or AIFF sound files Cutting, copying, splicing or mixing sounds together Changing the speed or pitch of a recording 44 Audio Hardware & Software ARDOUR Ardour belongs to the JACK Audio Connection Kit environment. It is one of the most efficient and professional audio editing and recording software available to the open source community. It is a complete digital audio workstation, useful for live recordings, concert recordings, and composition. For a complete list of features, visit http://www.ardour.org 45 Audio Hardware & Software JAMin JAMin is the Jack Audio Connection Kit Audio Mastering interface. JAMin is an open source application designed to perform professional audio mastering of stereo input streams. JAMin is licensed under the Gnu Public License (GPL). Linear filters JACK I/O 30 band graphic EQ Spectrum analyser 3 band peak compressor Lookahead brickwall limiter Multiband stereo processing Presets and scenes Loudness maximizer http://jamin.sourceforge.net/en/about.html 46 TEACH Form groups – assign YOUR numbers Study 1 audio editing software BUDDIES Exchange group mate – number group Brief - explain Go back to group - brief Q&A  SOFTWARE LIST https://alternativeto.net/ TENACITY https://tenacityaudio.org/ AUDACIUM https://audacium.github.io/audacium/ ARDOUR http://www.ardour.org JAMin http://jamin.sourceforge.net/en/about.html AUDIOMASS https://audiomass.co/ DARKAUDACITY http://www.darkaudacity.com/index.html RADIUM http://users.notam02.no/~kjetism/radium/index.php 48 THANK YOU MUCH!