What is the audio sample rate and how does it apply to microphones? In digital audio, the sample rate refers to how many individual samples of audio happen per second. Typically music audio is 44.1 kHz while video audio is 48 kHz. An audio interface (whether internal or external) will sample a mic’s analog signal at a given sample rate to convert it to digital audio.
Schneider Disc Technique:
What is the Schneider disc miking technique? The Schneider disc is a baffled near-coincident stereo pair miking technique. Like the Jecklin Disc, it utilizes a pair of omnidirectional mics roughly 20 cm apart and pointing 20° outward. It also has a centre disc, but with a sound-absorbing sphere in the middle to better simulate a human head.
What is a sealed microphone diaphragm? A sealed diaphragm has its rear side physically sealed off and under constant pressure. Sealed diaphragms are in omnidirectional pressure mics. The “sealed” chamber behind the rear side actually has a very small opening that allows it to maintain a constant pressure as the diaphragm moves.
Also known as Equivocal Noise Level.
What is microphone self-noise? Microphone self-noise is the noise inherent in the mic’s internal circuitry. Active mics will come with a self-noise spec that is given in an A-weighted decibel value (dBA).
For more information on microphone self-noise, check out my article What Is Microphone Self-Noise? (Equivalent Noise Level).
What is microphone sensitivity? Mic sensitivity is the relationship between the sound pressure level at the mic diaphragm and the signal strength at the mic output. It tells us how sensitive the mic is as a transducer. Output sensitivity ratings are typically tested with a 94 dB SPL 1 kHz tone at 1 meter from the capsule.
For more information on microphone sensitivity, check out my articles What Is Microphone Sensitivity? An In-Depth Description and What Is A Good Microphone Sensitivity Rating?
What is microphone separation? Separation is the ability of a microphone to reject the sound sources in a room that are intended to be picked up by other mics. Separation helps with phase issues and mixing. The space, position of the sound sources, and the mic placement, polar pattern, and sensitivity are factors in separation.
What is a microphone shock mount? A microphone shock mount is a device that fastens to a mic stand and holds a microphone while providing the mic with mechanical isolation. Shock mounts come in a variety of styles to suit different microphones and help to greatly reduce the amount of handling and mechanical noise in the mic signal.
For more information on microphone shock mounts, check out my article What Is A Microphone Shock Mount And Why Is It Important?
What is a microphone shootout? A microphone shootout is a way of comparing different mics against a sound source. A common shootout setup has multiple mics positioned closely together to record a single sound source. Another strategy uses multiple takes of a performance with a new mic swapped out in the same spot for each take.
To learn more about microphone shootouts, check out my article What Is A Microphone Shootout? (And How To Perform One).
What is a shotgun microphone? A shotgun microphone is highly directional and is often used as a boom mic in film production. The extreme directionality of shotgun mics is not possible in typical capsules, and so long interference tubes are utilized in order to filter out off-axis sound waves before they reach the diaphragm.
To learn more about shotgun microphones, please read the following My New Microphone articles:
• The Lobar/Shotgun Microphone Polar Pattern (With Mic Examples).
• Best Shotgun Microphones For A Camera.
• Best Boom Microphones For Film.
What is sibilance and how does it affect microphones? Sibilance is the high pitched whistle-like “S” sound inherent in the human voice. It is part of speech intelligibility but can also be overly harsh. Miking strategies to reduce excessive sibilance include turning the mic slightly off-axis, using a pop filter, or distancing the talent from the mic.
What is a microphone’s signal-to-noise ratio? A signal-to-noise ratio (SNR) is the difference between the signal strength and the noise in the signal, given in decibels. Active microphones have an output SNR the depends on their self-noise value. As the mic signal travels through a mic cable, EMI may potentially worsen the signal’s SNR.
For more info on microphones and their signal-to-noise ratios, check out my article What Is A Good Signal-To-Noise Ratio For A Microphone?
What does the term slate mean in reference to microphones? A slate is an announcement or visual that identifies what will be recorded and the take number of what is being recorded. Mics will record the slate audio, whether that’s a song title and take number in a studio or the clapstick sync on a film set.
Small-Diaphragm Condenser Microphone:
What is a small-diaphragm condenser microphone? A small-diaphragm condenser (SDC) generally has a diaphragm measuring half an inch or less in diameter. Compared to large-diaphragm condensers, SDCs have superior polar pattern consistency and transient and frequency responses but have higher self-noise. SDCs are typically top-address mics.
To learn more about small-diaphragm condenser microphones, check out my article Large-Diaphragm Vs. Small-Diaphragm Condenser Microphones.
What does the term “smeared” mean in reference to microphones? “Smeared” is a qualitative term for a sound that lacks clarity or a mic that picks up excessive reverberation and/or bleed from other sources.
What does “smooth” mean when referencing a microphone? “Smooth” is a general term for a microphone with a flat frequency response and subjectively pleasing sound.
Also known as a multicore cable.
What is an audio snake? An audio snake is a cable that carries multiple channels of audio between two points. Snakes provide a neater and easier cable run than individual cables when sending mic signals and other audio signals to a distant mixing console.
What are solid-state electronics and how does it apply to microphone technology? Solid-states electronics refers to any electronic equipment designed with semiconductive devices (semiconductive diodes, transistors, and integrated circuits). Microphone technology has benefitted greatly from transistors. FET and JFET condenser mics have become standard on the mic market.
Sound Incidence Angle:
What is a microphone’s sound incidence angle? The sound incident angle is the angle between the sound source and the primary axis of the microphone. Different polar patterns will yield different amounts of off-axis rejection at different sound incidence angles.
Sound Pressure Level:
What is sound pressure level and how does it affect microphones? Sound pressure level (SPL) is the measure of the strength of a sound wave. SPL is typically given as a decibel value (dB SPL) relative to the threshold of human hearing. SPL can also be described as the pressure variance from the atmospheric pressure (measured in Pascals). 1 Pa variance = 94 dB SPL.
What is sound reinforcement? Sound reinforcement is the amplification of the sound sources in a live performance, presentation, etc. Microphones are used to capture the sound sources as cleanly as possible. The mic signals are then amplified in multiple stages before getting sent to and emitted from monitors and loudspeakers.
What is a sound wave and how do sound waves affect microphones? A sound wave is a wave of compression and rarefaction that propagates through gaseous, liquid, and solid mediums. Sound waves affect mics by applying varying pressure to one or both sides of a mic diaphragm, causing the diaphragm to move and the mic to output a sympathetic electrical “mic” signal.
What does soundproof mean and why is soundproofing important to microphones? A soundproof acoustic space is a space that is ideally isolated from all external sound sources, preventing external sound from entering and internal sound from leaving the space. Soundproof spaces are important to microphones when clean recordings are required.
What is source impedance and why is it important to microphones? The source impedance is the output impedance of a device connected to an electrical load. When a mic (source) is sending a signal to a preamp (load), the source impedance is the output impedance of the mic. For optimal mic signal transfer, the load impedance should be at least 10x the source impedance.
What is the spaced cardioid miking technique? Spaced cardioids is a spaced pair stereo miking technique that positions a pair of cardioid mics several feet from one another, pointed them both directly at a sound source. Spaced cardioids yield a wide stereo image and maintain some isolation from sound sources to the rear.
What is the spaced omnis miking technique? Spaced omnis is a spaced pair stereo miking technique that positions a pair of omnidirectional mics several feet from one another and points them both directly at a sound source. Spaced omnis provide a wide, natural-sounding stereo image to help accentuate a stereo mix.
What is a spaced microphone pair? A spaced pair is a miking technique that positioned two identical microphones that are separated by several feet (usually one-third to one-half the width of a sound stage) and point directly at a sound source. Spaced pairs yield wide stereo images but typically have poor mono compatibility.
Spaced pair miking techniques include:
For more information on spaced pairs, check out my article What Is A Spaced Pair Of Microphones? (With 3 Techniques).
Also known as a datasheet.
What is a microphone specification sheet? A microphone specification sheet is a resource that shows a mic’s technical details. Mic spec sheets provide info on the polar pattern(s), frequency response(s), dimensions and weight. The sheet also offers ratings on sensitivity and impedance values and much more technical data on a microphone.
For information on microphone specification sheets, check out my article Full List Of Microphone Specifications (How To Read A Spec Sheet).
Spherical Microphone Array:
What is a spherical microphone array? The spherical microphone array is a miking technique for surround sound and 3-D playback formats. It consists of a spherical object with many mics mounted to it, all pointing in different but calculated directions. Processing the mic signals is required in the mix for the various playback formats.
Also known as accent-miking.
What is spot-miking? Spot-miking is the close-miking of a particular sound source in sound reinforcement. Spot-miking allows for increased clarity and presence of the miked source in a mix and is a popular technique on orchestral instruments that play crucial roles in a musical performance.
What is sputtering and why is it important to microphones? Sputtering is the process of applying a molecular-thin layer of metal to a surface. In the case of condenser mics, gold is often sputtered to the diaphragm to increase the diaphragm’s conductivity without affecting its movement. Gold is common because it is inert, nonoxidizing, and ductile.
To learn more about sputtering and its practice with microphones, check out my article Why Are Condenser Microphone Diaphragms Gold-Sputtered?
What is a squeeze microphone? A squeeze microphone refers to any mic that produces a mic signal that is later heavily compressed in a mix. Squeeze mics are often set up as room mics in a drum isolation booth. Their signals are used in parallel compression mixing techniques.
What is squelch and why is it important to microphones? Squelch is a circuit in a wireless microphone receiver that mutes the audio output if the signal strength drops below a certain threshold. Squelch suppresses the annoying sound of the channel and ambient noise when the mic is not sending an “important enough” signal.
What is a stage box? A stage box is a multichannel input box that typically attaches to the stage-end of an audio snake. Microphones and other audio devices send are plugged into the neatly laid out stage box and their signals are fed through the snake to the distant mixing console.
What is a step-up transformer and what role do step-up transformers play in microphone technology? A step-up transformer is an electric device that increases the AC voltage from the primary coil to the secondary coil without connecting the two in a circuit. Dynamic mics often have step-up Transformers to increase their output signal strength while protecting them from DC voltage (phantom power).
What is stereo audio and how does it apply to microphones? Stereo is a two-channel audio system with the left and right channels that approximates the binaural nature of human hearing. Stereo mixes require panning of channels in the left-to-right spectrum. There are many miking techniques that provide stereo images and there are even stereo microphones.
Stereo Ambient Sampling System:
What is the stereo ambient sampling system miking technique? The stereo ambient sampling system (SASS) is a baffled near-coincident stereo miking technique that used a pair of omnidirectional mics positioned less than a foot apart, angled at roughly 30°, and separated by a centre baffle. SASS yields a natural stereo sound and is great for recording ambiences.
What is a stereo bar for microphones? A stereo bar is a mounting device designed to hold a pair of microphones in place. Stereo bars are excellent for some coincident and near-coincident stereo miking techniques.
What is a stereo microphone? A stereo microphone is any mic that can output in stereo (two mono signals. Stereo mics are designed with at least two diaphragms set up as some sort of coincident pair. A stereo mic typically has a 5-pin XLR output and comes with a 5-pin to two 3-pin cable adapter for use with mic preamplifiers.
To learn more about stereo microphones, check out my article Do Microphones Output Mono Or Stereo Signals?
What is stereo miking? Stereo miking is a form of true stereo where two or more microphones are positioned to capture a stereo image of an acoustic space. The mic signals are panned according to their position in a stereo mix. Stereo miking techniques typically keep it simple with two mics panned left and right.
To learn more about stereo miking, check out my article Top 8 Best Stereo Miking Techniques (With Recommended Mics).
Here is a list of common stereo miking techniques by pair type:
For more information on coincident microphone pairs, check out my article What Is A Coincident Pair Of Microphones? (With 2 Techniques).
- DIN Pair
- EBS Pair
- Faulkner Array
- NOS Pair
- Olsen Stereo 180 Microphone Technique
- Olson Wing
- ORTF Pair
- RAI Pair
- Stereo Ambient Sampling System
- AB Technique (sometimes)
For more information on near-coincident microphone pairs, check out my article What Is A Near-Coincident Pair Of Microphones? (+7 Examples).
For more information on spaced microphone pairs, check out my article What Is A Spaced Pair Of Microphones? (With 3 Techniques).
Subcardioid Polar Pattern:
What is the subcardioid microphone polar pattern? The subcardioid polar pattern is a broad pickup unidirectional microphone polar pattern. Ideal subcardioids are a 7:3 ratio of omnidirectional to bidirectional patterns. Subcardioids have no null points but do have a 3-10 dB decrease in rear sensitivity compared to on-axis sensitivity.
To learn more about the subcardioid polar pattern, check out my article What Is A Subcardioid/Wide Cardioid Microphone? (With Mic Examples).
Supercardioid Polar Pattern:
What is the supercardioid microphone polar pattern? The supercardioid polar pattern is a highly directional microphone polar pattern. Ideal supercardioids are a 5:3 ratio of bidirectional to omnidirectional patterns. They are more directional than cardioids but have a rear lobe of sensitivity with null points at 127° and 233° (a cone of silence).
To learn more about the supercardioid polar pattern, check out my article What Is A Supercardioid Microphone? (Polar Pattern + Mic Examples).
What is a microphone supply voltage? A microphone supply voltage is a voltage needed to properly power an active mic. External voltages are needed to power the internal circuitry of active mics and to charge the capsules of true condenser mics. Supply voltages come from external power supplies, phantom power, or from DC-bias voltage.
What is surround sound and how does it apply to microphones? Surround sound is a method of enriching the listening experience with multiple audio channels from multiple speakers that surround the listener. Surround sound can be achieved in a mix by using pan pots. “True” surround sound, like true stereo, is captured by surround sound miking technique.
Surround Sound Miking
What is surround sound miking? Surround sound miking is typically “true-surround,” where each surround sound channel (left, right, centre, surround left, and surround right) has at least one microphone assigned to it for surround sound mixing. Some techniques (especially when recording ambience), however, drop the centre channel.
For more information on surround sound miking, check out my article Top 4 Best Surround Sound Miking Techniques (With 3 Extras).
Here is a list of common surround sound miking techniques:
- Ambisonic Array (when formatted to surround sound)
- Ambisonic Microphone (when formatted to surround sound)
- Ball Boundary Technique
- Cardioid Trapezoid
- Corey/Martin Tree
- Double Mid-Side Array
- Double ORTF Array
- Fukada Tree
- Hamasaki Surround System
- IRT Cross
- OCT Surround
- Omni+8 Surround
- Polyhymnia Pentagon
- Spherical Microphone Array
- Wide Cardioid Surround Array
What is suspension and why is it important to microphones? Suspension allows for relative motion and isolation between two connected objects. The suspension is critical in a microphone shock mount and is even designed into some mic capsules in order to provide the microphone with isolation from mechanically transmitted noise.
What is a microphone sweet spot? The sweet spot is the microphone position that yields the best sound of the given sound source in the given acoustic environment with the given musician/performer. Critical listening is invaluable when searching for a mic’s sweet spot since it’s rarely the same when the above variables are changed.