Microphones

Microphones come in a wide variety of styles: as headset units, desktop units, lapel units, handheld units and more. Whicever the style, you should consider a similar set of variations. These are:

Microphone Type: There are two types of microphones to choose from: Condenser and Dynamic. The selection of this specification depends on the scenario and equipment they will be connected to:

Condenser: Condenser microphones have a much greater frequency response, which is the ability to reproduce the "speed" of an instrument or voice. They also generally have a louder output, but are much more sensitive to loud sounds. They require the use of a power supply, generally 48 volt "phantom power", and that's supplied very easily by most mixing boards or external power supplies. On the downside, they are often more expensive than dynamic microphones, and due to more internal components are generally less durable.

Dynamic: Dynamic microphones don't require their own power supply like condenser microphones and are often cheaper and more durable than condenser microphones due to less internal components. On the downside, the sound quality is generally not as accurate as condenser microphones, and they support a limited frequency response.

Pickup Pattern: This specification refers to how the microphone picks up noises around it. There are several types of pickup patterns:

Omnidirectional

- Sound is picked up from all directions in a 360˚ radius.

Unidirectional

- Picks up sound predominantly from one direction.

Bidirectional

- Uses a figure-of-eight pattern and picks up sound equally from two opposite directions.

Sensitivity: This specification refers to how sensitive the microphone is to noise around it and its electrical output. This is usually presented using acronyms such as “dB” (decibels) or “dBV/Pa” (decibel to voltage). As reference levels, 0 dB SPL is the quietest sound a human can normally hear. For comparison, at three feet, speech conversation level is about 60 dB and a jackhammer's level is about 120 dB.

Impedance: This specification refers to the electrical output (ohms) the particular microphone requires to achieve its maximum signal strength. As a rule of thumb, first check the impedance of the device you’ll be connecting the microphone to and see if its supported impedance (ohms) is higher than the microphone. If a microphone is connected to an input with lower impedance, there will be a loss of signal strength.

Signal-to-Noise Ratio: The signal to noise ratio (S/N) is the difference in dB between a microphone's sensitivity and self noise. A higher S/N means that the signal is cleaner (less noise) and that the microphone has more "reach". Reach can be defined as the accurate pickup of quiet/distant sounds due to high S/N. As a general rule when evaluating S/N ratios, anything over 74dB is “excellent”, and an S/N specification of 64dB would be considered “good”.

Frequency Response: Frequency response measures how a microphone reacts to different sound frequencies. Typically, specification sheets will list frequency response as a range like "20Hz to 20kHz", meaning that the microphone can reproduce sounds that fall within that range. As a general rule of thumb, condenser vocal microphones have flatter frequency responses than dynamic. This means that a condenser would tend to be the better choice if accuracy of audio reproduction is the main goal.


IT Services recommends the following device(s), based on environment:

Office Use (Single User)

Logitech Desktop Microphone

- Wired USB (Plug-and-Play)

- Omnidirectional

- Noise Cancellation

- 100 Hz -16,000 Hz

 

logitechdeskmic

Price: $26.92 (CDWG)

Classroom Use (Multiple Users)

Logitech Desktop Microphone

- Wired USB (Plug-and-Play)

- 8 Built-in Microphones

- Adjustable Listening Presets

- Omnidirectional

- Noise Cancellation

- 100Hz to 11,250 Hz

 

acousticmagic

Price: $297.00 (AM)


For assistance with choosing a device, please check the IT Services Equipment Standards website or contact the Helpdesk.