Audio Fundamentals - Revision history

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 ===Wave Elements===
-All sounds that we hear are just air pressure variations hitting our ears at different rates. A speaker or piano radiates these variations of air pressure, while a microphone captures the variations. If you hit a drum of pluck a guitar, it makes sounds because it is moving back and forth repeatedly. When moving out, it produces higher pressure for air particles to squeeze together and then when moving back, the surface creates low pressure for air particles to spread out. This process repeats until the energy put into the drum or guitar has been dissipated and it stops moving. The high and low pressure repeating is a wave.
+All sounds that we hear are just air pressure variations hitting our ears at different rates. A speaker or piano radiates these variations of air pressure, while a microphone captures the variations. If you hit a drum or pluck a guitar, it makes sounds because it is moving back and forth repeatedly. When moving out, it produces higher pressure for air particles to squeeze together and then when moving back, the surface creates low pressure for air particles to spread out. This process repeats until the energy put into the drum or guitar has been dissipated and it stops moving. The high and low pressure repeating is a wave.
 *'''Frequency''''':'' The rate of the wave is called the frequency. Frequency is measured in how many times a cycle of high to low pressure occurs per second. The cycles per second can be measured in hertz (Hz). If a guitar string vibrates 440 cycles per second, we would call that a frequency of 440Hz. That 440Hz note would be called an A note because of the frequency. We hear frequency as higher or lower pitches. A high pitch bird song will be a much higher frequency like 10,000Hz and a low pitched bass note could be 60Hz. Frequency is pretty synonymous with tone, note and pitch.

@@ Line 60: / Line 60: @@
 === Microphone Basics ===
-All Microphones turn acoustic sound into analog signal. Depending on the mic, it may need to be supplied by a battery or "phantom power," which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to, such as a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphone Catalog|Microphones in General Access]] with information about each mics polar pattern, transducer type, uses and other useful information.
+All Microphones turn acoustic sound into analog signal. Depending on the mic, it may need to be supplied by a battery or "phantom power," which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to, such as a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphone Catalog]] with information about each mics polar pattern, transducer type, uses and other useful information.
 === Dynamic and Condenser Mics ===

@@ Line 60: / Line 60: @@
 === Microphone Basics ===
-All Microphones turn acoustic sound into analog signal. Depending on the mic, it may need to be supplied by a battery or "phantom power," which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to, such as a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphones in General Access]] with information about each mics polar pattern, transducer type, uses and other useful information.
+All Microphones turn acoustic sound into analog signal. Depending on the mic, it may need to be supplied by a battery or "phantom power," which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to, such as a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphone Catalog|Microphones in General Access]] with information about each mics polar pattern, transducer type, uses and other useful information.
 === Dynamic and Condenser Mics ===

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 The key decision in finding the right space is how you can best eliminate noise. You want to avoid fans, road noise, other people walking around, wind and any other unintended sound. It is hard to remove these kinds of sounds from a signal, it might be possible though if you use <u>noise reduction tools</u>, but don't expect it to. At this point in time, most recording is digital: your signal gets sent to a computer and turned into a file. Unless you put a tape in your device, it is most likely digital.
 * '''Studio:''' any room used for recording could be called a studio. Professional studios have a control room to separate the recording engineer from the performers. Evergreen has 4 General Access recording studios, and 5 recording studios with control rooms, but you need to be in an audio class to use them. You could record in any quiet room and get good results, you just have to consider not only noise, but how reverberant the room is. When you make a sound, can you hear that sound bounce around the room? This is usually caused by flat parallel surface. You can put up curtains, or other acoustic treatment techniques. There is no perfect audio system, you need to design it based on your needs, look at the Audio Systems Components above for ideas on where to get started.
-* '''Field:''' Field recording is anything that isn't in a studio, usually outside. People often use devices called field recorders which is like an all in one audio recording device. It functions as the mic, interface, computer, and speakers. Although most phones have these abilities too, a field recorder can capture much higher quality sound and has the ability to connect with professional microphones. The microphones that come on most field recorders like the LS-100 work great; they are in a stereo XY configuration, so you can get nice wide stereo sound or a whole field. If you want record a specific sound like an interview or a bird, you may want something more directional like a shotgun mic, like from the Sennheiser combo kit. Shotguns are often paired with windscreens and boom poles for getting sound for video. You could use a lavalier mic, which is a tiny mic that clips onto a person's shirt for high quality close mic'ing. For recording only one sound and rejecting all other sounds, Media Loan's best options is the parabolic mic kits, often used for nature recording and sports. You should always have headphones to monitor your sound. You never know when its going to rain, so it's a good idea to carry your gear in a dry bag, available at Media Loan. To reduce the noise of recording, it is good to use shock mounts for microphones like a boom pole, or a pistol grip.
+* '''Field:''' Field recording is anything that isn't in a studio, usually outside. People often use devices called field recorders which is like an all in one audio recording device. It functions as the mic, interface, computer, and speakers. Although most phones have these abilities too, a field recorder can capture much higher quality sound and has the ability to connect with professional microphones. The microphones that come on most field recorders like the LS-100 work great; they are in a stereo XY configuration, so you can get nice wide stereo sound or a whole field. If you want record a specific sound like an interview or a bird, you may want something more directional like a shotgun mic, like from the Sennheiser combo kit. Shotguns are often paired with windscreens and boom poles for getting sound for video. You could use a lavalier mic, which is a tiny mic that clips onto a person's shirt for high quality close mic'ing. For recording only one sound and rejecting all other sounds, Media Loan's best options are the parabolic mic kits, often used for nature recording and sports. You should always have headphones to monitor your sound. You never know when its going to rain, so it's a good idea to carry your gear in a dry bag, available at Media Loan. To reduce the noise of recording, it is good to use shock mounts for microphones like a boom pole, or a pistol grip.
 === Digital Audio ===
 Microphones create electrical signals that are analog signals. These analog signals are usually converted into digital signals, by being "sampled" by an Audio Interface. Digital signals are usually much easier to work with. They can be sent from one device to another, and be recorded and manipulated using digital audio tools.
-* '''Sample:''' A sample is the smallest unit to represent sound, it represents a single position of a speaker or microphone. You can think of it as the comparative air pressure associated with a single instance of the sound. It is like the frame of a movie. Movies usually have about 30 frames per second, whereas audio usually has 441,000 samples per second. As a side-note, modern music refers to small sections of sound as a sample which is a different use of the word, because an actual "sample" is just a single slice of audio that in itself doesn't sound like anything. All the samples put together in order make a waveform.
+* '''Sample:''' A sample is the smallest unit to represent sound, it represents a single position of a speaker or microphone. You can think of it as the comparative air pressure associated with a single instance of the sound. It is like the frame rate of a movie. Movies usually have about 30 frames per second, whereas audio usually has 44,100 samples per second (generally written as 44.1kHz). As a side-note, modern music refers to small sections of sound as a sample which is a different use of the word, because an actual "sample" is just a single slice of audio that in itself doesn't sound like anything. All the samples put together in order make a waveform.
-* '''Sample Rate:''' The sample rate is how many sample there are per second like the 44.1kHz is a common sample. Thats 44100 samples per second. Analog signal doesn't have samples, it is just a continuous stream of varying electrical level with infinite temporal resolution. You are losing sound information by converting the signal from an analog signal to digital signal, but most people can't hear the difference, which is why most audio work is done digitally.
+* '''Sample Rate:''' The sample rate is how many sample there are per second like the 44.1kHz is a common sample rate. Thats 44,100 samples per second. Analog signal doesn't have samples, it is just a continuous stream of varying electrical level with infinite temporal resolution. You are losing sound information by converting the signal from an analog signal to digital signal, but most people can't hear the difference, which is why most audio work is done digitally.
 * '''Bit-Depth:''' A samples resolution is defined by it's bit-depth which is how many 1's and 0's are required to describe each sample. A higher bit-depth means each individual sample has more possible positions it could be in.
-* '''File Type:''' Once recorded, these 1's and 0's are stored as a file. There are many file types, Mp3 may be the most recognizable, but it is better to use higher quality ones like .wav or .flac if possible. CD's and DVD's are made possible by the ability to have 1's and 0's being represented as a either a tiny reflective (1) on non reflective (0) surface on the plastic. Tapes and records on the other hand are analog and have infinite detail between what would be reduced to a sample.
+* '''File Type:''' Once recorded, these 1's and 0's are stored as a file. There are many file types, MP3 may be the most recognizable, but it is better to use higher quality ones like .wav or .flac if possible. CD's and DVD's are made possible by the ability to have 1's and 0's being represented as either a tiny reflective (1) or non reflective (0) surface on the plastic. Tapes and records on the other hand are analog and have infinite detail between what would be reduced to a sample.
 * '''Artifacts:''' All of these medium and tools have "audio artifacts" which are errors that indicate the medium being used. You can hear the blockiness of low quality youtube videos, you can hear the tape pitch warble on a run down tape deck, a vinyl record player might get stuck and loop a couple times. all of these problems are good to be aware of an can be used to trick the user into thinking that they are listening to one medium rather than another.
 === DAW ===
-Digital Audio Workstation, or Daw for short, is versatile tool for recording and editing your audio. There are many different kinds, but they all rely on the same principle of sound design, so if you learn one, you can learn the others. they have a Mixer view or some kind usually at the bottom to represent the sam kinds of controls you would have on a physical mixer. There is also a track view, where you get to see the waveforms recorded, from left to right, in each track stacked vertically. Most DAWs have the ability to use Midi which might be in a midi track, mixed in with all the audio channels.
+Digital Audio Workstation, or DAW for short, is versatile tool for recording and editing your audio. There are many different kinds, but they all rely on the same principle of sound design, so if you learn one, you can learn the others. They have a mixer view or some kind usually at the bottom to represent the same kinds of controls you would have on a physical mixer. There is also a track view, where you get to see the waveforms recorded, from left to right, in each track stacked vertically. Most DAWs have the ability to use midi which might be in a midi track, mixed in with all the audio channels.
-* '''Recording:''' You can either bring in recorded file from a field recording or record directly from an interface. the interface will have different channels that you will want to connect to the channels of the virtual mixer (usually at the bottom). this is done with I/0 or input/output. find those word on a channel and select the channel that you want to record. sometime interface aren't recognized instantly so you may need to go into the DAW or the computer preferences to enable the interface as your audio device.
+* '''Recording:''' You can either bring in recorded file from a field recording or record directly from an interface. The interface will have different channels that you will want to connect to the channels of the virtual mixer (usually at the bottom). This is done with I/0 or input/output. Find these labels on a channel and select the input that you want to record. Sometimes, interfaces aren't recognized instantly so you may need to go into the DAW or the computer preferences to enable the interface as your audio device.
-* '''MIDI:''' is a very powerful tool in DAWs. It is the representation of musical note information like pitch, velocity (like volume) and timing. It in itself doesn't make sound, but it is very useful because you can tell virtual instrument to make sound. It also can connect to many kinds of audio gear using a MIDI cable, or nowadays a USB cable, to carry MIDI signals.
+* '''MIDI:''' Midi is a very powerful tool in DAWs. It is the representation of musical note information like pitch, velocity (volume) and timing. It in itself doesn't make sound, but it is very useful because you can tell virtual instruments to make sound based on the notes in midi data. It also can connect to many kinds of audio gear using a MIDI cable, or nowadays a USB cable, to carry MIDI signals.
-* '''Mixing:''' On a computer, audio mixing is similar to if not interchangeable with the concept of audio editing. You are adjusting gain (volume) of each channel, adding effects(listed below), and adding "automations" to adjust those qualities over time. You can sequence midi, or chop up and move around audio  layering
+* '''Mixing:''' On a computer, audio mixing is similar to if not interchangeable with the concept of audio editing. You are adjusting gain (volume) of each channel, adding effects, and adding "automations" to adjust those qualities over time. You can sequence midi, or chop up and move around audio  layering
 === Recording Workflow ===
 # Test out your equipment and space before your performer gets there. Make sure you are getting clean signal with no noise.
-# With your musician run a mic check and set your trim (described in the above <u>[https://helpwiki.evergreen.edu/wiki/index.php/Audio_Fundamentals#Audio_Concepts gain staging section]</u>).
+# With your musician, run a mic check and set your gain (described in the above <u>[https://helpwiki.evergreen.edu/wiki/index.php/Audio_Fundamentals#Audio_Concepts gain staging section]</u>).
 # Make sure that the performer can hear what they need to; themselves, what is being recorded, the pre-recorded sounds, whatever they need.
 # Record the take, check it, continue.
-# Save your files in at least 2 locations for safety. There are audio files that you want to save. If you are using a DAW there is what is called a project file where you do your mixing and effect in a timeline. it is just a simple file that notes what audio files and when on the timeline in addition to any effects you might use. You will want to save this and the audio files together. Many times the program will make a folder to hold all these files, but it is good to check what and where your files were saved to before closing out of the program to make sure you have everything you need.<span id="PA"></span>
+# Save your files in at least 2 locations for safety. There are audio files that you want to save. If you are using a DAW there is what is called a project file where you do your mixing and effect in a timeline. It is just a simple file that notes what audio files and when on the timeline in addition to any effects you might use. You will want to save this and the audio files together. Many times the program will make a folder to hold all these files, but it is good to check what and where your files were saved to before closing out of the program to make sure you have everything you need.<span id="PA"></span>
 [[Category:Media Loan Topics]]
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 ** [[File:Cardioid.png|frameless|25x25px]] '''Cardioid:''' Sound is picked up in a heart shaped pattern in front of the mic. This allows you to focus on one sound while excluding other sounds. Also all directional mics are omni directional with low frequencies. This means that a cardioid mic may pick up low frequencies outside of its pick up pattern.
 **  [[File:SuperCardioid.png|frameless|25x25px]]'''Super-Cardioid:''' Mics have a narrower pattern in the front but they also have a small lobe in the back of the pattern.
-**  [[File:SuperCardioid.png|frameless|25x25px]]'''Hyper-Cardioid:''' Used with shotgun mics. They have a very narrow pattern in the front. They have a rear lobe like the super-cardioid, but they also have lobes on the side of the mic. They are used to focus in a specific direction. You need to pay attention to the side lobes. If you are standing next to a noisy camera with a shotgun mic the side lobes might pick up the camera along with the intended sounds
+**  [[File:HyperCardioid.png|frameless|25x25px]]'''Hyper-Cardioid:''' Used with shotgun mics. They have a very narrow pattern in the front. They have a rear lobe like the super-cardioid, but they also have lobes on the side of the mic. They are used to focus in a specific direction. You need to pay attention to the side lobes. If you are standing next to a noisy camera with a shotgun mic the side lobes might pick up the camera along with the intended sounds
-* '''Bi-Directional:''' This pattern is less common than the others. Sound is picked up from either side of the mic. There are no bi-directional mics in Media Loan’s General Access. Most ribbon mics are bi-directional, and some fancy large diaphragm condensers have variable pickup patterns including bi-directional.
+* [[File:Bidirectional.png|frameless|25x25px]]'''Bi-Directional:''' This pattern is less common than the others. Sound is picked up from either side of the mic. There are no bi-directional mics in Media Loan’s General Access. Most ribbon mics are bi-directional, and some fancy large diaphragm condensers have variable pickup patterns including bi-directional.
 === Noise Avoidance ===

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 ===Wave Elements===
 All sounds we hear are just air pressure variations hitting our ears at different rates. A speaker or piano radiates these variations of air pressure, while a microphone captures the variations. If you hit a drum of pluck a guitar, it makes sounds because it is moving back and forth repeatedly. When moving out, it produces higher pressure for air particles to squeeze together and then when moving back, the surface creates low pressure for air particles to spread out. This process repeats until the energy put into the drum or guitar has been dissipated and it stops moving. The high and low pressure repeating is a wave.
-*'''Frequency''''':'' The rate of the wave is called the frequency. Frequency is measured in how many times a cycle of high then low pressure occurs per second. The cycles per second can be measured in hertz (Hz). If a guitar string vibrates 440 cycles per second, we would call that a frequency of 440Hz. That 440Hz note would be called an A note because of the frequency. We hear frequency as higher or lower pitches. A high pitch bird song will be a much higher frequency like 10,000Hz and a low pitched bass note could be 60Hz. Frequency is pretty synonymous with tone, note and pitch.
+*'''Frequency''''':'' The rate of the wave is called the frequency. Frequency is measured in how many times a cycle of high to low pressure occurs per second. The cycles per second can be measured in hertz (Hz). If a guitar string vibrates 440 cycles per second, we would call that a frequency of 440Hz. That 440Hz note would be called an A note because of the frequency. We hear frequency as higher or lower pitches. A high pitch bird song will be a much higher frequency like 10,000Hz and a low pitched bass note could be 60Hz. Frequency is pretty synonymous with tone, note and pitch.
 *'''Amplitude:''' The intensity of the wave is called the amplitude, we hear this as loudness and often describe it as volume. If you pluck the guitar string twice as hard and get the wave to oscillate back and forth twice as far, it has twice the amplitude and therefore we hear it as louder. Another common measurement of intensity is deciBels or dB. It is like an averaging of amplitudes over time.
@@ Line 84: / Line 84: @@
 There are a lot of different bad noises to consider when using microphones.
 * '''Location:''' You want to be in a quiet room, or a space that has environmental noise that you want. If you are in a room with a loud fan, fridge buzz, etc, it will make a noisy recording. If you want location sounds, you could add them in later, but if you know you want to have bird chirping, or loud coffeeshop chatter in the back of interview, these noises can work to your advantage.
-* '''Placement:''' You want the mic to be close enough to your source that it is picking up the person or instrument more than anything else, but not so close that it starts to get too "boomy" where the low frequencies get picked up more than others. This boomy-ness from close micing is because of what it called proximity effect.
+* '''Placement:''' You want the mic to be close enough to your source that it is picking up the person or instrument more than anything else, but not so close that it starts to get too "boomy" where the low frequencies get picked up more than others. This boomy-ness from close mic'ing is because of what is called proximity effect.
-* '''Mic Bumps:''' Handling the mic or bumping the mic stand will make a noise that can be hard to effectively remove later. It is best to avoid these noises. some mics are build to enduring handling noise better like the SM58. For field recording, you could use a shock mount like the boom pole or pistol grip to minimize handling noise for shotgun microphones.
+* '''Mic Bumps:''' Handling the mic or bumping the mic stand will make a noise that can be hard to effectively remove later. It is best to avoid these noises. Some mics are built to endure handling noise better, like the Shure SM58. For field recording, you could use a shock mount like the boom pole or pistol grip to minimize handling noise for shotgun microphones.
-* '''Pops''': You can use a pop filter or a windscreen to help reduce some bad sounds that might get recorded on a microphone. when people make "B" or "P" sounds they generate a big burst of air that will hit the microphone and not sound very good. These are called "plosives". Using a pop filter helps break up that burst of air and you are only left with good natural sounds vocals. These pop filters can also help reduce the sharp "S" sounds that can get unnaturally picked up by microphones. these are called "sibilance".
+* '''Pops''': You can use a pop filter or a windscreen to help reduce some bad sounds that might get recorded on a microphone. When people make "B" or "P" sounds they generate a big burst of air that will hit the microphone and not sound very good. These are called "plosives."  Using a pop filter helps break up that burst of air and you are only left with good natural sounding vocals. These pop filters can also help reduce the sharp "S" sounds that can get unnaturally picked up by microphones, called "sibilance".
-* '''Feedback:''' This is a really scary thing to deal with in audio, but you only need to worry about it if you have speakers and microphones in the same space and the speaker is amplifying what the microphone is picking up. It is called feedback because the mic picks up itself on the speakers which then amplifies itself and it feeds back until it makes an extremely loud whining sound. The easies thing to do to avoid this is have your mic in a different space than the speakers, but if you need them to be together, you could be sure the mics are pointed away from the speakers, so they wont pick them up. Do mic tests to make sure that with your placement, it wont feedback.
+* '''Feedback:''' This is a really scary thing to deal with in audio, but you only need to worry about it if you have speakers and microphones in the same space and the speaker is amplifying what the microphone is picking up. It is called feedback because the mic picks up itself on the speakers, which then amplifies itself and it feeds back until it makes an extremely loud whining sound. The easiest thing to do to avoid this is have your mic in a different space than the speakers, but if you need them to be together, you could be sure the mics are pointed away from the speakers, so they wont pick them up. Do mic tests to make sure that with your placement, it won't feedback.
 === Extra Microphone Details ===
@@ Line 108: / Line 108: @@
 ===<span id="Audio Concepts"></span>Audio Concepts===
 * '''Signal Flow:''' Sound waves in the air can be turned into an electrical signal called an analog signal using a microphone, mixed with other signal using a mixer, then sent back out as a new physical sound waves using a speaker. No matter the size or complexity of the system, it is important to think of it in terms of signal flow. What order is the signal flowing through different cables and gear, and what is happening to the audio at each step? This line of thinking will help with quick adjustments and <u>[[Troubleshooting Media Equipment|troubleshooting issues]]</u>.
-* '''Gain Staging''':  An important concept to know is Mic vs line level signal. Microphones output a very weak signal out their cables, so whatever it is connected to needs to use a "preamplifier" to amplify that signal to a level so that it can withstand going through circuits and being recorded. a Preamp brings a mic level up to line level which is about 1000x bigger to Line level. is this process you face the biggest decision of gain staging, for more info on that read the gain staging section below. You need to choose if your signal is mic or line level as it goes into the preamp that may be in a mixer or interface.
+* '''Gain Staging''':  An important concept to know is mic vs line level signal. Microphones output a very weak signal out of their cables, so whatever it is connected to needs to use a "preamplifier" to amplify that signal to a level so that it can withstand going through circuits and being recorded. A preamp brings a mic level up to line level. In this process you face the biggest decision of gain staging, for more info on that read the gain staging section below. You need to choose if your signal is mic or line level as it goes into the preamp that may be in a mixer or audio interface.
-* '''Stereo:''' We have two ears, so we can simulate sounds in space by using stereo audio. Instead of one "channel" of audio, there are two different ones. One is the left channel, and the other is the right channel. These will go to each left and right speaker or headphone and ultimately the left and right each. Most Audio tools can use "panning" to control what goes to the left or right speaker, but most of the time it is a combination of bother or the same. Most songs and movies will be stereo and have some aspect that can be heard, like the back ground vocals will be spread out between the left and right channels, or a car driving by will be heard going from left to right. You can also record in stereo where you use two microphones instead of one.  You would then take the audio from one mic and put it in one speaker, then the audio from the other mic in to the other speaker. Many audio field recorders like the H4n have built in stereo mics because they are a popular mic technique for field recording.
+* '''Stereo:''' We have two ears, so we can simulate sounds in space by using stereo audio. Instead of one "channel" of audio, there are two different ones. One is the left channel, and the other is the right channel. These will go to each left and right speaker or headphone and ultimately the left and right ear. Most audio tools can use "panning" to control what goes to the left or right speaker, but most of the time it is a combination of both or the same. Most songs and movies will be stereo and have some aspect that can be heard, like the back ground vocals will be spread out between the left and right channels, or a car driving by will be heard going from left to right. You can also record in stereo where you use two microphones instead of one.  You would then take the audio from one mic and put it in one speaker, then the audio from the other mic in to the other speaker. Many audio field recorders like the H4n have built in stereo mics because they are a popular mic technique for field recording.
 ===Audio System Components===

@@ Line 60: / Line 60: @@
 === Microphone Basics ===
-All Microphones turn acoustic sound into analog signal. Depending on the mic it may need to be supplied by a battery or "phantom power" which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to like a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphones in General Access]] with information about each mics polar pattern, transducer type, uses and other useful information.
+All Microphones turn acoustic sound into analog signal. Depending on the mic, it may need to be supplied by a battery or "phantom power," which is usually 48 volts of electricity sent to the mic from whatever you are connecting it to, such as a mixer. There is often a button that says "48v" to enable it. You can do a lot with microphones and there is a great variety of them used for different purposes. We have a catalog of [[Microphones in General Access]] with information about each mics polar pattern, transducer type, uses and other useful information.
 === Dynamic and Condenser Mics ===
@@ Line 67: / Line 67: @@
 * '''Condenser''': Mics are more sensitive and can pick up faster transients. They also require power. Many of the condensers available in General Access can be powered by a battery. Some of the condensers can be powered from phantom power. Phantom power is a power source that is supplied through the mic cable from a mixer or field recorder. Media Loan has mixers available for checkout that can supply phantom power. Zoom H4n and Olympus LS-100 field recorders are also capable of supplying phantom power.
 * '''Other:''' These are less common types of transducers
-** '''Ribbon:''' We don't have these in General Access, but for those in audio programs that get to use them. These are extremely fragile and will break when you use Phantom Power, so be certain that phantom power is turned off when plugging it in to the input. This is a small strip of magnetized metal ribbon that responds to air pressure variations and affects a large magnets electrical charge.
+** '''Ribbon:''' We don't have these in General Access, but for those in audio programs that get to use them. These are extremely fragile and will break when you use phantom power, so be certain that phantom power is turned off when plugging it in to the input. This is a small strip of magnetized metal ribbon that responds to air pressure variations and affects a large magnet's electrical charge.
-** '''Contact''': Another lesser used transducer type. It is often a small crystal that creates an electrical charge when impacted by pressure variations. Media Loan only has contact microphone called hydrophone and is literally the only mic that should be anywhere near water at all.
+** '''Contact''': Another lesser used transducer type. It is often a small crystal that creates an electrical charge when impacted by pressure variations. Media Loan only has one contact microphone called the hydrophone and is literally the only mic that should be anywhere near water at all.
 === Mic Pickup Patterns ===
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 * [[File:Omni.png|frameless|25x25px]] '''Omni-Directional:'''  Mic picks up sound from all directions.
-* '''Uni-Directional:''' These are mics that pick up best in one direction. The uni-directional category is broken down into cardioid, Super-Cardioid, and hyper-cardioid.
+* '''Uni-Directional:''' These are mics that pick up best in one direction. The uni-directional category is broken down into cardioid, super-Cardioid, and hyper-cardioid subcategories:
-** [[File:Cardioid.png|frameless|25x25px]] '''Cardioid:''' Mics pick up sound in a heart shaped pattern in front of the mic. This allows you to focus on one sound while excluding other sounds. Also all directional mics are omni directional with low frequencies. This means that a cardioid mic may pick up low frequencies outside of it’s pick up pattern
+** [[File:Cardioid.png|frameless|25x25px]] '''Cardioid:''' Sound is picked up in a heart shaped pattern in front of the mic. This allows you to focus on one sound while excluding other sounds. Also all directional mics are omni directional with low frequencies. This means that a cardioid mic may pick up low frequencies outside of its pick up pattern.
 **  [[File:SuperCardioid.png|frameless|25x25px]]'''Super-Cardioid:''' Mics have a narrower pattern in the front but they also have a small lobe in the back of the pattern.
-**  [[File:SuperCardioid.png|frameless|25x25px]]'''Hyper-Cardioid:''' or shotgun mics have a very narrow pattern in the front. They have a rear lobe like the Super-Cardioid but they also have lobes on the side of the mic. They are used to focus in a specific direction. You need to pay attention to the side lobes. If you are standing next to a noisy camera with a shotgun mic the side lobes might pick up the camera along with the intended sounds
+**  [[File:SuperCardioid.png|frameless|25x25px]]'''Hyper-Cardioid:''' Used with shotgun mics. They have a very narrow pattern in the front. They have a rear lobe like the super-cardioid, but they also have lobes on the side of the mic. They are used to focus in a specific direction. You need to pay attention to the side lobes. If you are standing next to a noisy camera with a shotgun mic the side lobes might pick up the camera along with the intended sounds
-* '''Bi-Directional:''' This Pattern is less common than the others. The mic picks up sound from either side of the mic. There are no bi-directional mics in Media Loan’s General Access. All ribbons are Bi-Directional. Some fancy Large Diaphragm Condensers have variable pickup patterns including Directional
+* '''Bi-Directional:''' This pattern is less common than the others. Sound is picked up from either side of the mic. There are no bi-directional mics in Media Loan’s General Access. Most ribbon mics are bi-directional, and some fancy large diaphragm condensers have variable pickup patterns including bi-directional.
 === Noise Avoidance ===
-there are a lot of different bad noises to consider when using microphones.
+There are a lot of different bad noises to consider when using microphones.
 * '''Location:''' You want to be in a quiet room, or a space that has environmental noise that you want. If you are in a room with a loud fan, fridge buzz, etc, it will make a noisy recording. If you want location sounds, you could add them in later, but if you know you want to have bird chirping, or loud coffeeshop chatter in the back of interview, these noises can work to your advantage.
 * '''Placement:''' You want the mic to be close enough to your source that it is picking up the person or instrument more than anything else, but not so close that it starts to get too "boomy" where the low frequencies get picked up more than others. This boomy-ness from close micing is because of what it called proximity effect.

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 ===Audio System Components===
 There are categories used to identify audio gear, but many items combine elements from multiple categories. For example, a mixer may also act as an interface. It is important to be aware of these categories and that they may be combined depending on the gear.
-*'''Microphone:''' See [https://helpwiki.evergreen.edu/wiki/index.php/Audio_Fundamentals#Audio_Concepts#MICROPHONES MICROPHONES] section above.
+*'''Microphone:''' See [https://helpwiki.evergreen.edu/wiki/index.php/Audio_Fundamentals#MICROPHONES MICROPHONES] section above.
 *'''Cable:''' For most uses, cables are straight forward, you find the cable with a plug that connects to the socket you want to connect. The most common are XLR, 1/4", 1/8" (mini 3.5mm aux), and RCA. If you don't know what connector you need, you can look up your equipment make and model to find a manual with connector information. USB and other computer cables can carry digital audio signal if your gear is designed to utilize it. For advanced systems, you may want to learn the difference between balanced and unbalanced signal.