The Perfect Pickup: Mics

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The process of selecting the right equipment for the station often involves careful research into the needs of the users, and then matching these needs to the available choices. The available budget also figures into this equation, but it can sometimes have some flexibility based on the features.

It's amazing how often this process is ignored when it comes to selecting a microphone. It's easy to think that a mic is a mic. They all pick up sound. They all cover the audio spectrum. In general this is true, but the same careful consideration given to an audio processor can be applied to a microphone. Just as an audio processor has its own nuances and feel, so does a microphone.

For studio use, these nuances and the general specifications are the key aspects to consider. The studio mic sees as much regular use as any other piece of equipment, so a minor price difference should not be a limiting factor.

As a review, there are two general categories that can describe any mic. One category covers the mics electrical operation. The other details its pickup pattern.

For the electrical aspect, all mics can be categorized as either dynamic or active (usually condensers). Dynamic mics are purely passive devices. Sound resonates a diaphragm that creates a signal voltage. Ribbon mics, while not as common in regular use, are also categorized as dynamic mics, but because of their low output level and fragile construction, are not typically found in regular use for radio.

The other electrical type of mic is the condenser. In condenser mics, the pickup diaphragm affects a capacitor with an electrical charge on it. As sound waves move the diaphragm the capacitance changes, thereby causing changes to the electrical charge, which results in an output signal.

Both types are practical for use in a studio. Dynamic mics require no external power, so they do not require any special installation. Most condenser mics operate on phantom power — a power supply that is carried over the balanced audio path. Most current console designs and mic preamps can provide phantom power. Some condenser mics use batteries or require an external power supply.

Evaluating the sound quality of a dynamic or condenser mic is a subjective test. In general, condenser mics tend to cost more than dynamics. Some feel that condenser mics have a crisper, more present sound. While either is suitable for use in a studio, dynamic mics are usually preferred for field use because they do not need batteries or a phantom power supply, which few portable devices can provide.

The second general categorization of mics deals with the pick up pattern. In most radio applications an omnidirectional or cardioid pattern is used. There are other directional patterns, including super-cardioid, hyper-cardioid and figure eight or bidirectional, but they are not as commonly used in on-air applications. Some studio mics offer switchable patterns. This is a convenient feature in some applications, but is usually not necessary for the single-function use of a mic in a studio.

All cardioid mics exhibit proximity effect. This is an increase in bass response as the signal source gets closer to the mic. Some mic designs acoustically reduce this effect, which can prevent a mic's sound from becoming boomy when used closely. Also, many cardioid mics have a bass roll-off switch to tailor the low-end response. Announcers love proximity effect because of the richness it adds to the sound of their voices.

In a studio, either pattern will work, but most engineers prefer a cardioid pickup. The cardioid pattern by nature reduces the level of sounds from the side and rear of the microphone. This is particularly useful in a studio with more than one mic in use.

For field use, a cardioid mic is best when used only by one person. The reduction in unwanted sound is a benefit. However, if the mic will be used for interviews where the mic is shared, an omnidirectional pickup would ensure that all voices are heard equally.

The tonal quality of a mic is just as important as its application. As the first link in the audio chain, take the time to fully evaluate your next mic choice. You may be surprised at what you hear.

Resource Guide
An overview of available mics for the studio

The Studio Projects C1 is a cardioid condenser microphone with a 1.06" capsule, low-noise FET amplifier and balanced, transformerless output circuitry. It features a switchable 10dB pad and a 6dB at 150Hz high-pass filter. It includes a shock-mounted elastic suspension, foam wind screen and a hard-side carrying case. The mic's frequency response is from 20Hz to 20kHz with a maximum input of 142dB. The output impedance is less than 200ohms. It operates on phantom power.


The Audio-Technica AT3060 is a large-diaphragm, side-address, cardioid condenser element with a tube output. It does not require a dedicated power supply or special cable because it operates exclusively on 48Vdc phantom power. The hand-selected tubes are individually tested and aged to maintain peak performance. The tubes are shock-mounted to dampen mechanically-coupled vibrations. Large coupling transformer improves the low-frequency linearity. It features a 50Hz to 16kHz frequency response, 400ohms output impedance, a 117dB dynamic range and a maximum input level of 134dB. It includes a shock mount and protective pouch.


The Rode Broadcaster is an end-address, cardioid mic with a 20Hz to 20kHz frequency response and an output impedance of 40ohms. This large-diaphragm condenser mic includes a unique on-air indicator LED that can be connected to a studio's warning light. It has an internal shock-mounted capsule to reduce structure-borne noise and a fine mesh pop shield to eliminate plosives. It is housed in a rugged stainless-steel body and features a voice-tailored low-cut filter. It includes the BM1 microphone holder and a zip pouch.


The Electro-Voice RE27 N/D is a large-diaphragm dynamic mic featuring the Electro-Voice Variable-D design to reduce the significant increase in bass response from the proximity effect of the cardioid pickup. The N/DYM element design provides a 6dB increase in sensitivity compared to other dynamic mic designs. The integral wind and blast filter reduces breath noise and plosive transients. Frequency response is from 45Hz to 20kHz. The output impedance is 150ohms. It has three selectable filters (bass roll-off, low-mid cut and high-frequency roll-off) to tailor the frequency response. The mic includes a stand adapter, carrying pouch and hard-shell case.


A hyper-cardioid condenser mic, the Lawson Air features an original capsule design using a variant of the company's L47 capsule. The mic is a 48V phantom-powered, 1" large-diaphragm cardioid condenser mic with a six-micron gold-sputtered diaphragm. The capsule diaphragms have been edge-connected for more warmth, robust articulation and more resonant proximity effects. The mic features the Lawson Quick Change capsule system. The mic's solid-state circuit features a Neutrik transformer, hand-soldered all-discrete components and a gold-plated XLR connector. It features 20Hz to 20kHz frequency response and 150ohms output impedance. It includes a shock-proof carrying case and swivel mic holder.


The Sennheiser MD 421 II continues the tradition of the MD 421, which has been one of Sennheiser's most popular dynamic mics for more than 35 years. The large-diaphragm, cardioid dynamic element handles high sound-pressure levels. The mic features a five-position bass control switch to tailor the bass response. The frequency response is from 30Hz to 17kHz. The Nominal output impedance is 200ohms. To celebrate the 90th birthday of the company's founder, Fritz Sennheiser, a special-edition MD 421 SE with gold-plated hardware, a wooden case and a signed certificate was issued.


The AKG Acoustics C 4500B-BC is a cardioid, condenser microphone with transformerless output. Its all-metal housing and double-screening of all acoustically open sections of the microphone provide shielding capability. The C 4500B-BC offers a front-end firing capsule position, electro-magnetic screening and internal pop-filter. A 120Hz roll-off filter is integrated into the C 4500B-BC, while a 20dB pad allows users to replace dynamic microphones without changing the adjusted gain structure on associated equipment. The low self-noise and high overload point of the AKG C 4500B-BC offer a dynamic range of more than 135dB. The output impedance is 200ohms and frequency response is 20Hz to 20kHz.


The Shure KSM27 is a side-address condenser microphone with a cardioid polar pattern. It has an externally biased, 1" gold-layered diaphragm, low self-noise, a 20Hz to 20kHz frequency response and a Class A, discrete, transformerless preamplifier. It features a subsonic filter to eliminate rumble from mechanical vibration below 17Hz, a switchable 15dB pad, a three-position switchable low-frequency roll-off filter, an integrated three-stage pop protection grille and an internal shock mount. It can handle an input level of 137dB. It includes a protective pouch.


Built by Audio-Technica and based on the A-T 40 Series, the Sound Performance Lab Nugget condenser mic uses a 1" diaphragm and transformerless circuitry for accurate, musical reproduction with a maximum input of 145dB SPL. It features a switchable 50Hz high-pass filter and 10dB pad. The mic was designed for vocal and instrumental recording applications. A high-quality shock mount is included. The cardioid pattern has a 20Hz to 20kHz frequency response, a 129dB dynamic range, 50ohms output impedance and a 78dB S/N. It includes a suspension shock mount.


The Neumann TLM 103 large-diaphragm, cardioid condenser microphone uses the transformerless circuit found in numerous Neumann microphones and features low self-noise and high sound pressure level capability. The mic is available in satin nickel and matte black finishes. The mic provides flat frequency response to 5kHz with a 4dB presence boost in higher frequencies. It is capable of handling sound pressure levels up to 138dB. The K 103 large diaphragm capsule is based on the K 87, well known from the U 67/U 87 microphones.


The Heil Sound Goldline Pro dynamic mic achieves a low handling noise by mounting the wide frequency, dynamic element into a sorbothane shock-mount system. The mic has also been engineered to reduce the bass boost from proximity effect. It features a large aluminum 1.125" low-mass voice-coil assembly. The phasing plug assembly has equally placed ports that sense audio from behind the mic to produce a linear cardioid pattern. The frequency response is from 40Hz to 18kHz. It has a 600ohm output impedance. It includes a wooden case. A shock mount is also available.


The SE Electronics Z-2200 features discrete Class A FET electronics with a transformer-coupled balanced output. The mic's frequency response is from 20Hz to 20kHz and can handle a maximum input of 125dB. The audio response has a slight rise towards the high end. Its output impedance is less than 200ohms. Features include a 100Hz bass roll-off switch and a 10dB pad. The pickup pattern is a fixed cardioid. The mic's gold-sputtered diaphragm measures 1.07". The mic has a 3dB to 6dB lower self-noise than the company's previous models.


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