audio production chapter 4 and 5 test #2
price for capsule for mic
$400
far-field monitoring
- larger, full-range loudspeakers - typically built-in to wall structure - located several feet from listener Loudspeakers used for far field monitoring are usually large and can deliver very wide frequency response at moderate to quite loud levels with relative accuracy Monitoring sound at the listening position from large, powerful frontal loudspeakers several feet away and usually built into the mixing-room wall provides highest quality sound reproduction Near field monitoring enables the sound engineer to reduce the audibility of control room acoustics, particularly the early reflections, by placing loudspeakers close to the monitoring position Consisting of large loudspeaker systems that can deliver very wide frequency response at moderate to quite loud levels with relative accuracy
Low impedance mics and equipment have 3 advantages over high impedance mics
-They generate less noise -They were much less susceptible to hum and electrical interference such as static -They can be connected to long cables without increasing noise impedance- resistance to the flow of voltage in a circuit Pro mics usually range in impedance from 150 to 600 ohms
mono speaker
1-all sound coming out of 1 speaker tone sound not detailed. More drivers more details all info coming out of one source No distinct left and right Good for voice, news
balanced line
2 conductors and a shield. a three-wire microphone cable designed to minimize electrical interference
Microphone modeler
A device or plug-in that emulates the sound of various microphones. microphone stimulator that can be added to a digital audio workstation as a plug in. emulates the sounds of mics
transducer
A device that converts energy from one form to another Like the loudspeaker, the mic is a transducers- a device that converts one form of energy into another but it works in the opposite direction: instead of changing electrical energy into acoustic energy as the loudspeaker does, the mic changes acoustic energy into electrical energy. The electric energy flows through a circuit as voltage Loudspeaker turns electrical energy into acoustic energy. Mic turns acoustic energy into electrical energy
windscreens
A foam or metallic mesh microphone shield that reduces wind noise Pop onto microphone and help reduce the sound of wind Good to have when outside especially Windscreens and pop filters Deals w distortion that results from blowing sounds caused by breathing and wind. An external shock mount, or a built in shock absorber, is used to prevent unwanted vibrations from reaching the microphone element Mounted externally Slightly affect response
intermodulation distortion
A form of distortion that introduces frequencies not present in the original signal; These are invariably based on the sum and difference products of the original frequencies. results when 2 or more frequencies occur at the same time and interact to create combination tones and dissonances that were not present originally Sound distortions from two different sources trying to produce the same pitch The noise that occurs when the frequencies of two or more signals mix together and create new frequencies. When 2 or more frequencies occur at the same time and interact to create combination tones and dissonances that are unrelated to the original sounds Audio systems can be most vulnerable to IM distortion when frequencies are far apart Usually occurs in high frequencies bc they are weaker and more delicate than the low frequencies Harmonic and IM distortion usually happen when the input and output of a sound system are nonlinear-when they do not change in direct proportion to each other
shotgun mic
A highly directional mic for picking up sounds from a relatively great distance. Another type of condenser mic A directional mic with an extremely narrow pick-up pattern. a highly directional microphone, usually with a long, tubular body Used on a boompole Hones in on one precise area A microphone with an extremely directional pickup pattern. A highly directional mic for picking up sounds from a relatively great distance They attenuate sound from all directions except a narrow angle at the front Usually used for speech Does Not pick up anything to left and right of speaking but has sensitivity ain the back of the microphone Designed for long distance pickup Picks up all outdoor sounds Dead cat used on shotgun mic
polarity
A lack of electrical symmetry in a molecule Polarity probs can occur between woofer and tweefer in same loudspeaker enclosure or between 2 separate loudspeakers Sound is out of phase When one loudspeaker is pushing sound outward, and other is pulling sound inward. If sound level meters show a similar level and the audio still sounds skewed, the speakers are out of phase. If they show diff levels, the phase problem is probably elsewhere
active ribbon microphone
A ribbon microphone that uses an amplifier system requiring phantom power. phantom power: -phantom power -a method of remotely powering an amplifier or impedance converter by sending voltages along the audio cable Active ribbons better than conventional ribbons bc higher output and sensitivity, wider and flatter frequency response and the ability to handle higher sound levels
overload
All mics will distort if sound levels are too high aka overload Moving coil and capacitor mics are not as vulnerable to distortion caused by excessive loudness as are ribbon mics. ribbon mics more vulnerable to distortion Overload distortion-results when a signal is recorded or played back at an amplitude greater than the sound system can handle creates a fuzzy, gritty sound
Amplifier power
Amplifier power must be sufficient to drive the loudspeaker system, or distortion will result At least 30 watts for tweeters and 100W for woofers are generally necessary Amplifier power means a proportional increase in loudness
proximity effect
Bidirectional and most directional mics are susceptible to proximity effect-An increase in the level of bass frequencies relative to midrange and treble frequencies when they are placed close to a sound source When any mic is placed close to a sound source, bass frequencies increase in level relative to midrange and treble frequencies To neutralize proximity effect, most of these mics are equipped w a bass roll off
ribbon mic
Has very thin ribbon that moves and gives it a nice warm recording Good for instruments or voiceover The most sensitive type of mic used in television A thin ribbon of metal surrounded by a magnetic field Old fashioned Has relatively low mass Not widely used today The 2 types of pro mics that use magnetic induction are the moving coil mics and the ribbon mics Instead a moving coil, it uses a metal ribbon attached to a fixed magnet In earlier ribbon mics, the ribbon is situated vertically. In modern ribbon mics, the ribbon is situated horizontally Employ magnetic induction-uses a fixed magnet and a movable diapragm to which a small, lightweight, finely wrapped coil is attached Active ribbon mics-use an amplifier system which requires phantom power -a method of remotely powering an amplifier or impedance converter by sending voltages along the audio cable -Active ribbons better than conventional ribbons bc higher output and sensitivity, wider and flatter frequency response and the ability to handle higher sound levels
noise cancelling headphones
Headphones can be detrimental to hearing bc they are mounted directly over the ears, or with earbuds, placed inside the ears. To help reduce the potential of hearing loss is the active noise-cancelling headphone which detects ambient noise before it reaches the ears and nullifies it by synthesizing the sound waves
calibration
Helps ensure that a systems measurements meet a specified or desired standard Spectrum analyzer- device that displays the frequency response of an electrical waveform in relation to the amplitude present at all frequencies
headphones
Important part of monitoring When using headphones for professional purposes: -Frequency response should be wide, flat and uncolored -Must be thoroughly familiar with their sonic characteristics -Should be circumaural (around the ear) -Must be as airtight as possible against the head for acoustical isolation -Must be comfortable -Stereo headphones should be used for stereo monitoring and headphones capable of multichannel reproduction should be used for monitoring surround sound Headphones can be detrimental to hearing bc they are mounted directly over the ears, or with earbuds, placed inside the ears. To help reduce the potential of hearing loss is the active noise-cancelling headphone which detects ambient noise before it reaches the ears and nullifies it by synthesizing the sound waves For detailed listening, use headphones. Headphones very detailed Speakers are good way for mixing and if bringing in delay and reverb. Little bit of interaction w the room.
monitor sound
In adjusting and evaluating monitor sound, both objective and subjective measures are necessary Headphones are an Important part of monitoring When evaluating the sound of a monitor loudspeaker, it is helpful to, among other things, use material you are intimately familiar with and to test various loudspeaker responses with different types of speech and music
Carotid/unidirectional
Looks like a heart Heart shaped pattern in front of the microphone Actively rejecting sounds in back of mic Good studio mic gets you and little bits of left and right but nothing behind you most popular Directional from one side Hears sound mainly from the front Directional sensitivity in a unidrectional mic varies w frequency. The higher the frequency, the more directional the pickup. The lower the frequency, the less drectional the pickup
dynamic range
Loudspeakers in professional studios have a dynamic range of up to 80 dB. The dynamic range in consumer loudspeakers in considerably less. Even the better ones may be only 55 dB. the range of amplitudes that can be heard and discriminated To meet most any sonic demand, the main studio monitors should have an output-level capability of 120 dB-SPL and a dynamic range of up to 80 dB An output capability of 120 dB is good Limited dynamic range in iphones and computers reduces audio quality
Linearity
Means that a frequency fed in at 1 loudness output is at the same loudness Frequencies being fed to a loudspeaker at a particular loudness are reproduced at the same loudness How even it is Consideration in evaluating frequency response in a loudspeaker Frequency fed in at one loudness is output same
Dynamic/moving coil Microphone
Meant to be handheld Microphone that uses a traditional magnet to create the audio signal Rugged, durable mic; uses small coil that moves within a magnetic field to produce a signal Don't require power. Just plug it in. based on magnets Picture on slide is SM58. SM stands for studio microphone Works with magnetism Moving coil mics are available in all pickup patterns except bidirectional Mics that use the magnetic induction principle-includes the moving coil and ribbon transducers Hum is a problem in dynamic mics Aka moving coil The 2 types of pro mics that use magnetic induction are the moving coil mics and the ribbon mics Moving coil/dynamic and capacitor mics are not as vulnerable to distortion caused by excessive loudness as are ribbon mics. Moving coil mics can take high levels of loudness without internal damage
Sensitivity
Measures the voltage that a mic produces (dBv) at a certain sound pressure level. Indicates how loud a mic is Sensitivity is the on axis sound pressure level (SPL) a loudspeaker produces at a given distance when driven at a certain power. A monitor's sensitivity rating provides a good overall indication of its efficiency. A monitor's sensitivity Gives you an idea of the system's overalll efficiency 93 or louder required for professional applications the amount of output for a given input Measures the voltage that a mic produces in dBV Indicates how loud a mic is Sensitivity does not affect a mics sound quality but it can affect the overall sound quality of a recording
cables
Mic cable is either a balanced line or an unbalanced line Balanced line- 2 conductors and a shield. a three-wire microphone cable designed to minimize electrical interference Unbalanced line-one conductor with the shield serving as the second conductor
Microphone frequency response
Mics have a frequency response so they aren't totally linear Similar to equal loudness principle Linear-whats coming into mic is exactly whats going out of mic Every microphone has a mic frequency response chart like this The range of frequencies that it produces at an equal level, within a margin of -+3 dB. Its frequency response curve can be displayed as a graph For professional purposes it is preferable to flush-mount loudspeakers in a wall or soffit to make low frequency response more efficient and to reduce or eliminate back-wall reflections, cancellation, and cabinet edge diffraction an audio system's ability to reproduce a range of frequencies with the same relative loudness The range of frequencies that a mic reproduces at an equal level within a margin of +-3 dB. Graph shows our entire range of human hearing frequencies. 20 to 20k hZ Indicates how faithfully it transduces acoustic energy into electric signals and with what correlation, if any In a loudspeaker involves 2 considerations how wide it is and how flat, or linear, it is
microphone direction
Mics pick up sound from 3 directions-omnidirectional(all around), bidirectional(front and rear), and unidirectional/cartoid(front only, narrower pickup patterns-supercaroid, hypercardiod, and ultracardiod)
surround sound
Multiple audio channels; usually 5-7 channels. Breaks the sound A type of audio processing that makes the listener experience sound as if it were coming from all directions. Differs from stereo by expanding the dimension of depth, thereby placing the listener more in the center of the aural image than in front of it The most common surround sound format uses 6 discrete audio channels- 5 full range and 1 limited to low frequencies(subwoofer). Format is 5.1. Subwoofer can be placed anywhere in room bc low frequencies are relatively omnidirectional but it is usually situated in the front Not just the same sound coming out of 5 speakers. Diff sounds Set up on powerpoint is aka 5.1-left speaker, right speaker, left rear, right rear, etc In pro tools can pan left to right The more you have, the more you are immersed in sonic environment Movie theatres usually 7.1 or 9.1. 7 or 9 speakers Surround sound differs from stereo by expanding the depth dimension, thereby placing the listener more in the center of the aural image than in front of it. Therefore using the 5.1 surround sound format, monitors are positioned front-left center and front-right and the surround loudspeakers are placed left and right behind or to the rear sides of, the console operator. Stereo headphones should be used for stereo monitoring and headphones capable of multichannel reproduction should be used for monitoring surround sound
hum
Particularly a prob in dynamic mics There are several ways to minimize hum Humbucking-cancels the effect of hum. Effected w a humbuck coil
Omnidirectional
Pickup pattern of a microphone that can hear equally well from all directions. circular picking up sounds from every angle Interview mics are often omnidirectional bc get sounds of environment and person 2nd most popular
PZM (boundary mic)
Pressure zone microphone Also condenser mic. Requires power Intended to pick up sounds of people all around it and eliminated reverb. Only recording indirect sound Good for conferences and theater
pop filter/blast filter
Prevents blasts of air from hitting microphone A wire-mesh screen attached to the front of a mic that reduces breath pops and sudden air blasts. Windscreens and pop filters Deals w distortion that results from blowing sounds caused by breathing and wind and popping sounds Built in and is most effective against blowing sounds and popping Mainly found in moving coil, newer ribbon and some capacitor mics used in omnidirectional mics
Shockmount
Reduced vibrations from the mic stand that produce unwanted sounds Maintains vibrations a rubber cradle mic suspension device Reduces noise induced by vibrations Device that suspends and mechanically isolates the mic from the stand Some mics have a shock absorber built in
Near-field monitoring
Reduces the audibility of control room acoustics by placing loudspeakers close to the listening position monitoring with loudspeakers placed close to the operator, usually on or just behind the console's meter bridge, to reduce interference from control room acoustics at the monitoring position reduces the audibility of control room acoustics by placing loudspeakers close to the listening position smaller, limited range loudspeakers, set on stands or console bridge, located near to listening position (room acoustics do not affect listener) smaller monitor speakers placed very near the mixing position, often at the front of the console Near-field monitoring allows the operator to hear a more direct sound Have a built in high pass filter to protect the bass unit from overload
transients
Sounds that begin with a quick attack, such as a drum hit or breaking glass and then rapidly decay condenser/capacitor mics Have the lowest mass of the 3 types of professional mics which makes them best suited to handle transient sounds
spectrum analyzer
Spectrum analyzer- device that displays the frequency response of an electrical waveform in relation to the amplitude present at all frequencies
stereo sound
Stereo creates the illusion of 2 dimensional sound by imaging depth-front to back and width-side to side in aural space defines the horizontal audio field Two audio tracks create an illusion of space and dimension. 2 dimensional-it has depth and breadth Have to be placed symmetrically to reproduce an accurate and balanced front to back and side to side sonic image Designated stereo listening position- sweet spot
Polar patterns/directional characteristics
Tells you how to use mic and the direction Pick up pattern aka polar response pattern-the directions from which a mic hears sound Mics work in a 3 dimensional soundfield. Sounds arrive at mics from all directions Moving coil/dynamic mics are available in all pickup patterns except bidirectional A mic does not reach out to pick up sound Mics pick up sound from 3 directions-omnidirectional(all around), bidirectional(front and rear), and unidirectional/cartoid(front only, narrower pickup patterns-supercaroid, hypercardiod, and ultracardiod) A mics directional sensititivty can be displayed graphically in a polar response diagram Capacitor/condensor mics come in all pickup patterns
dead cat
The Fuzzy wind screen that fits over the shotgun Microphone Extreme form of a windscreen
distortion
The appearance of a signal in the reproduced sound that was not in the original sound If an audio signal level is too high for a particular component to cope with, then parts of the signal will be lost. This results in the rasping distorted sound Screaming into mic and it causes crackle sound If audio signal is too high for a component to deal with Overloading a speaker or mic more than it can handle Any component in the sound chain can generate distortion Loudspeakers are the most distortion prone component in most audio systems if you bring gain up too high it can distort Amplifier power must be sufficient to drive the loudspeaker system, or distortion will result To help protect against loudness distortion, many capacitor mics are equipped w a pad to reduce overloading the mic's electronics Various forms of distortion include intermodulation, harmonic, transient, and loudness intermodulation distortion: When 2 or more frequencies occur at the same time and interact to create combination tones and dissonances that are unrelated to the original sounds Audio systems can be most vulnerable to IM distortion when frequencies are far apart Usually occurs in high frequencies bc they are weaker and more delicate than the low frequencies .... harmonic distortion: occurs when the audio system introduces harmonics into a recording that were not present originally Nonlinear distortion caused when an audio system introduces harmonics to a signal at the output that were not present at the input. harmonics in output not present at input The production of waveform harmonics that do not exist in the original signal Harmonic and IM distortion usually happen when the input and output of a sound system are nonlinear-when they do not change in direct proportion to each other .... transient distortion: relates to the inability of an audio component to respond quickly to a rapidly changing signal, such as that produced by percussive sounds Sometimes produces a ringing sound system cannot accurately reproduce rapid "attack" .... loudness distortion/overload distortion: results when a signal is recorded or played back at an amplitude greater than the sound system can handle results when a signal is recorded or played back at an amplitude greater than the sound system can handle Creates a fuzzy, gritty sound CLIPPING when a signal is recorded or played back at an SPL that is more than the sound system can handle. All mics will distort if sound levels are too high aka overload Moving coil and capacitor mics are not as vulnerable to distortion caused by excessive loudness as are ribbon mics
Self-Noise/Equivalent Noise Level
The electrical noise, or hiss, an electronic device/mic produces Electrical noise generated by mic itself In relation to microphones, S/N (signal to noise ratio) is the difference between sound pressure level and self noise Aka equivalent noise level
polar response
The indication of how a loudspeaker focuses sound at the monitoring position(s). how a loudspeaker focuses sound at the listening position
Coverage Angle
The off-axis angle or point at which the loudspeaker level is down 6 dB compared with the on-axis output level.
signal-to-noise ratio (SNR or S/N)
The proportion of noise to the strength of a signal. The ratio of a signal power to the noise power corrupting the signal and is measured by decibels The diff between sound pressure level and self noise In relation to microphones, S/N is the difference between sound pressure level and self noise
variable capacitance
The type of pro mic using variable capacitance is the capacitor mic
Capacitor Microphone
The type of pro mic using variable capacitance is the capacitor mic Not meant to be handheld A high-quality, sensitive microphone for critical sound pickup Uses variable capacitance A type of mic that requires an external power supply to operate Always requires a source of power Have the lowest mass of the 3 types of professional mics which makes them best suited to handle transient sounds -Transients- sounds that begin w a quick attack and then rapidly decay Mics operating on the variable capacitance principle tranduce energy using voltage(electrostatic) variations instead of magnetic(electromagnetic)variations and are called capacitor microphones Capacitor mics come in all pickup patterns More of a studio mic. Put on a stand To help protect against loudness distortion, many capacitor mics are equipped w a pad to reduce overloading the mic's electronics Ex, lavalier, shotgun, PZM Capacitor mics require a power supply to operate
arrival time
Time of arrival of the first wave A sound's arrival time at the monitoring positions should be no more than 1 ms; otherwise, aural perception is impaired distance between a seismic station and the earthquake epicenter is determined from arrival time
Microphones
Transducers that convert acoustic energy into electrical energy. The device that does the transducing is called the element A standard mic is used w wireless systems in one of 3 ways- mini mic, handheld, and boom The elements in pro mics operate on one of 2 physical principles-magnetic induction and variable capacitance Pro mics and equipment are low impedance the moving coil mics and the ribbon mics use magnetic induction The type of pro mic using variable capacitance is the capacitor mic Mics work in a 3 dimensional soundfield. Sounds arrive at mics from all directions Like the loudspeaker, the mic is a transducers- a device that converts one form of energy into another but it works in the opposite direction: instead of changing electrical energy into acoustic energy as the loudspeaker does, the mic changes acoustic energy into electrical energy. The electric energy flows through a circuit as voltage Some mic models are dual element, combining the moving coil and capacitor designs or incorporating two capacitor or 2 moving coil designs Each type of mic is unique. One type is not so much better than another as it is more suitable for a particular application Mics pick up sound from 3 directions-omnidirectional(all around), bidirectional(front and rear), and unidirectional/cartoid(front only, narrower pickup patterns-supercaroid, hypercardiod, and ultracardiod) When choosing a mic, consider 3 basic features: operating principles, directional characteristics, and sound response (more could be appearance, cost and durability)
SM57
Used for presidential podium More for instruments Dynamic mic very popular
Passive crossover network
Uses filters to pass only certain frequencies. -Uses filters to pass only certain frequencies. -In a Passive crossover network, the power amplifier is external to the speakers and precedes the crossover -Can create problems-distortion more likely to occur at loud levels and harmonic distortion may be heard at high frequencies -Passive loudspeakers- Loudspeakers that are powered externally
proximity effect/bass tip up
When any mic is placed close to a sound source, bass frequencies increase in level relative to mid range and treble frequencies Bidirectional and most directional mics are susceptible to proximity effect An increase in the level of bass frequencies relative to mid range and treble frequencies when they are placed close to a sound source To neutralize proximity effect, most of these mics are equipped w a bass roll off
placement of loudspeaker
Where a loudspeaker is positioned affects sound dispersion and loudness. A loudspeaker in the middle of a room generates the least concentrated sound; a loudspeaker at the intersection of a ceiling or floor generates the most
connectors
XLR connectors-3 pin plug
four way system loudspeaker
a loudspeaker system with three crossover networks More efficient and yield better sound quality
passive loudspeakers
a loudspeaker that is powered externally An external amplifier feeds power to the speaker elements
active loudspeakers
a loudspeaker that is powered internally Power amps are built in and each speaker element has its own amplifier
phantom power
a method of remotely powering an amplifier or impedance converter by sending voltages along the audio cable. The power for preamplification in a condenser microphone, supplied by the audio console rather than a battery. Low voltage power used by Condensor Microphones A method of remotely powering an amplifier or impedance converter by sending voltage along the audio cable Provides the fixed charge for a condenser microphone Active ribbon mics-use an amplifier system which requires phantom power--better than passive bc have higher output and sensitivity, wider and flatter frequency response and the ability to handle higher sound levels before distortion Passive mics do not require phantom power
Lavalier Microphone
a small microphone designed to pick up speech from a single person, typically attached to the subject's clothing with a specialized clip Type of capacitor/condensor mic entirely hands free Small microphone typically used to mic individual people Used when filming someone in corner of room 2 types-proximity prone mini mic and the transparent mini mic Designed to be unobtrusive
loudspeakers
aka monitors transducers essentially reversing the process of a microphone most speakers are dynamic like a dynamic mic. Using electric to push sound through the room reproduce sound A single, mid sized speaker cannot reproduce high and low frequencies very well; it is essentially a midrange instrument no 2 loudspeakers sound quite the same factors that decide which loudspeaker s best- frequency response, linearity, amplifier power, distortion, dynamic range, sensitivity, polar response, arrival time, and polarity A sound's arrival time at the monitoring positions should be no more than 1 ms; otherwise, aural perception is impaired Transducers that convert electrical energy into sound energy A loudspeaker should be able to reproduce all frequencies linearly-output=input Powered either externally or internally Passive loudspeakers- Loudspeakers that are powered externally. An external amplifier feeds power to the speaker elements speakers and mics are called transducers-take 1 form of energy and convert it into another form of energy. Mic turns acoustic energy into electrical energy. Loudspeaker turns electrical energy into acoustic energy For improved response, loudspeakers have drivers large enough to handle the bass frequencies and drivers small enough to handle the treble frequencies. These drivers are called woofers and tweeters Polarity problems can occur between woofer and tweeter in the same loudspeaker enclosure or between 2 separate loudspeakers Where a loudspeaker is positioned affects sound dispersion and loudness. A loudspeaker in the middle of a room generates the least concentrated sound; a loudspeaker at the intersection of a ceiling or floor generates the most Many studios use at least 2 types of studio monitors Studios use 2 or 3 sets of diff loudspeakers to try to get a handle on what produced audio will sound like on the variety of receivers out there Amplifier power must be sufficient to drive the loudspeaker system, or distortion will result Loudspeakers in professional studios have a dynamic range of up to 80 dB. The dynamic range in consumer loudspeakers in considerably less. Even the better ones may be only 55 dB. Sensitivity is the on axis sound pressure level (SPL) a loudspeaker produces at a given distance when driven at a certain power. A monitor's sensitivity rating provides a good overall indication of its efficiency. Polar response- indicates how a loudspeaker focuses sound at the monitoring position(s)
Humbucking
cancels the effect of hum. Effected w a humbuck coil
maximum sound pressure level
db level at which distortion begins The level at which a mic's signal begins to distort A max sound pressure level of 120 dB is good, 135 is very good, and 150 dB is excellent The level at which a microphone's output signal begins to distort, that is, produces a 3 percent total harmonic distortion.
sweet spot
designated stereo listening position
crossover network
electronic equipment that sends high-frequency sound to tweeters and low to woofers A crossover network separates the bass and the treble frequencies at the crossover point, or crossover frequency and directs them to their particular drivers In a Passive crossover network, the power amplifier is external to the speakers and precedes the crossover. In an active crossover network, the crossover precedes the power amps. Widens the loudspeakers frequency response and makes reproduction of the bass and the treble more efficient 2 way system loudspeakers have one crossover network, three way system loudspeakers have 2 crossovers, and 4 way system loudspeakers have 3 crossovers two way system loudspeaker-if a loudspeaker system divides the frequency spectrum once. The crossover frequency in a two way system is in the neighborhood of 1500 to 2000 Hz. has 1 crossover network divides the frequency spectrum between the low and high frequences crossover frequency- the actual point or frequency where the bass and treble divide For improved response, loudspeakers have drivers large enough to handle the bass frequencies and drivers small enough to handle the treble frequencies. These drivers are called woofers and tweeters ..... passive crossover network: -Uses filters to pass only certain frequencies. -In a Passive crossover network, the power amplifier is external to the speakers and precedes the crossover -Can create problems-distortion more likely to occur at loud levels and harmonic distortion may be heard at high frequencies -Passive loudspeakers- Loudspeakers that are powered externally active: the crossover precedes the power amps and operates at low power levels Active loudspeakers-powered internally Has more advantages over a passive one-less expensive, reduces distortion, power use more efficient bc a lower power amp can drive the tweeter, transient response is better esp in lower frequencies Disadvantage-if entire amp fails, the entire speaker has to be serviced
Head Room
extra bit so you aren't forcing the equipment to do something that it cant
bidirectional
functioning in two directions Aka figure 8 microphone Picking up both people at same time equally. Has 2 equal sides of directionality 2 people can speak into either end of it and get it Ribbon mic is bidirectional Least sensitive to sounds coming from the sides Bidirectional and most directional mics are susceptible to proximity effect-An increase in the level of bass frequencies relative to midrange and treble frequencies when they are placed close to a sound source -When any mic is placed close to a sound source, bass frequencies increase in level relative to midrange and treble frequencies
two-way system loudspeaker
if a loudspeaker system divides the frequency spectrum once. The crossover frequency in a two way system is in the neighborhood of 1500 to 2000 Hz. has 1 crossover network
drivers
individual speaker elements that were developed to handle the different physical requirements necessary to emit the long, powerful bass frequencies and the short, more directional treble frequencies For improved response, loudspeakers have drivers large enough to handle the bass frequencies and drivers small enough to handle the treble frequencies. These drivers are called woofers and tweeters polarity probs can occur between woofer and tweeter in the same loudspeaker enclosure or between 2 separate loudspeakers more drivers more details
woofers
large speakers that reproduce low sounds crossover network-electronic equipment that sends high-frequency sound to tweeters and low to woofers
The elements in pro mics operate on one of 2 physical principles
magnetic induction and variable capacitance
sound level analyzer
measures in ear monitoring levels to guard against excessive loudness
A standard mic is used w wireless systems in one of 3 ways
mini mic, handheld, and boom
Harmonic distortion
occurs when the audio system introduces harmonics into a recording that were not present originally Nonlinear distortion caused when an audio system introduces harmonics to a signal at the output that were not present at the input. harmonics in output not present at input The production of waveform harmonics that do not exist in the original signal Harmonic and IM distortion usually happen when the input and output of a sound system are nonlinear-when they do not change in direct proportion to each other
unbalanced line
one conductor with the shield serving as the second conductor
2 types of lavalier microphones
proximity prone mini mic and the transparent mini mic
transient distortion
relates to the inability of an audio component to respond quickly to a rapidly changing signal, such as that produced by percussive sounds Sometimes produces a ringing sound system cannot accurately reproduce rapid "attack" Distortion that occurs when a sound system cannot reproduce sounds that begin with sudden, explosive attacks. When some component cannot respond quickly enough to a rapidly changing signal Results from insufficient damping
overload/loudness distortion
results when a signal is recorded or played back at an amplitude greater than the sound system can handle Creates a fuzzy, gritty sound CLIPPING when a signal is recorded or played back at an SPL that is more than the sound system can handle. All mics will distort if sound levels are too high aka overload Moving coil and capacitor mics are not as vulnerable to distortion caused by excessive loudness as are ribbon mics
tweeters
small speakers that reproduce high sounds crossover network-electronic equipment that sends high-frequency sound to tweeters and low to woofers
stereo
solid, 3-dimensional Requires 2 speakers 2 speakers, headphones built in left and right Hear slight differences in left and right
transient
sounds that begin w a quick attack and then rapidly decay condenser mics have the lowest mass of the 3 types of professional mics which makes them best suited to handle transient sounds
Impedance
the acoustic resistance to sound traveling in a medium resistance to the flow of voltage in a circuit. The lower the impedance, the better Pro mics and equipment are low impedance The property of a circuit, or an element that restricts the flow of alternating current (ac) Measured in ohms, a unit of resistance to current flow The lower the impedance the better Low impedance mics and equipment have 3 advantages over high impedance mics: -They generate less noise -They were much less susceptible to hum and electrical interference such as static -They can be connected to long cables without increasing noise Pro mics usually range in impedance from 150 to 600 ohms
crossover frequency
the actual point or frequency where the bass and treble divide
sound chain
the audio components that carry a signal from its sound source to its destination begins w the mic, whose signal is sent to a console or mixer for routing and then processed, reocrded and heard through a loudspeaker the quality of every sound evaluated is based on what you hear from a loudspeaker interacting with the room acoustics
Active crossover network
the crossover precedes the power amps and operates at low power levels Active loudspeakers-powered internally Has more advantages over a passive one-less expensive, reduces distortion, power use more efficient bc a lower power amp can drive the tweeter, transient response is better esp in lower frequencies Disadvantage-if entire amp fails, the entire speaker has to be serviced
element
the device that does the transducing in a mic mounted in the mic head Each type of mic gets its name from the element it uses Elements operate on one of 2 physical principles-magnetic induction and variable capacitance
Pick up pattern aka polar response pattern
the directions from which a mic hears sound
The 2 types of pro mics that use magnetic induction are
the moving coil mics and the ribbon mics
IEM/In ear monitor
used by musicians in live concerts to replace stage monitors A sound level analyzer-measures in ear monitoring levels to guard against excessive loudness Allows a performer to hear a mix of on stage microhpones or instruments or both, and provides a high level of noise reduction for ear protection. Since their development, IEMs are used for other monitoring purposes.
magnetic induction
used by the moving coil mics and the ribbon mics Elements operate on one of 2 physical principles-magnetic induction and variable capacitance Uses a fixed magnet and a movable diaphragm to which a small, lightweight, finely wrapped coil suspended between the poles of a fixed magnet is attached
movie theatres surround sound
usually 7.1 or 9.1. 7 or 9 speakers