Mackie M1200/M1400 owner manual Signal whose level falls between -10 dBu and +30 dBu

Maintaining proper circuit impedance rela- tionships is important to avoid distortion and minimize added noise. Mackie input and out- put impedances are designed to work well with the vast majority of audio equipment.

knee

A knee is a sharp bend in an EQ response curve not unlike the sharp bend in your leg. Also used in describing dynamics processors.

level

Another word for signal voltage, power, strength, or volume. Audio signals are some- times classified according to their level. Commonly used levels are: microphone level (–40 dBu or lower), instrument level (–20 to –10 dBu), and line level (–10 to +30 dBu).

line level

A signal whose level falls between –10 dBu and +30 dBu.

master

A control affecting the final output of a

mixer. A mixer may have several master con- trols, which may be slide faders or rotary controls.

mixer

An electronic device used to combine vari- ous audio signals into a common output. Different from a blender, which combines vari- ous fruits into a common libation.

monaural

Literally, pertaining to or having the use of only one ear. In sound work, monaural has to do with a signal which, for purposes of commu- nicating audio information, has been confined to a single channel. One microphone is a mono pickup; many microphones mixed to one chan- nel is a mono mix; a mono signal played through two speakers is still mono, since it only carries one channel of information. Several monaural sources, however, can be panned into a stereo (or at least two-channel, if you are going to be picky) mix. Monaural sound rein- forcement is common for environments where stereo sound reinforcement would provide an uneven reproduction to the listener.

monitor

In sound reinforcement, monitor speakers (or monitor headphones or in-the-ear monitors) are those speakers used by the per-

formers to hear themselves. Monitor speakers are also called foldback speakers. In recording, the monitor speakers are those used by the production staff to listen to the recording as it progresses. In zoology, the monitor lizard is the lizard that observes the production staff as the recording progresses. Keep the lizard out of the mixer.

noise

Whatever you don’t want to hear. Could be hum, buzz, or hiss; could be crosstalk or digital hash or your neighbor’s stereo; could be white noise or pink noise or brown noise; or it could be your mother-in-law reliving the day she had her gallstone removed.

noise floor

The residual level of noise in any system. In a well-designed product, the noise floor will be a very quiet hiss, which is the thermal noise generated by bouncing electrons in the transis- tor junctions. The lower the noise floor and the higher the headroom, the more usable dynamic range a system has.

parametric EQ

A “fully” parametric EQ is an extremely pow- erful equalizer that allows smooth, continuous control of each of the three primary EQ param- eters (frequency, gain, and bandwidth) in each section independently. “Semi” parametric EQs allow control of fewer parameters, usually fre- quency and gain (i.e., they have a fixed bandwidth, but variable center frequency and gain).

peaking

The opposite of dipping, of course. A peak is an EQ curve that looks like a hill, or a peak. Peaking with an equalizer amplifies a band of frequencies.

phone jack

Ever see those old telephone switchboards with hundreds of jacks and patch cords and plugs? Those are phone jacks and plugs, now widely used with musical instruments and audio equipment. A phone jack is the female connector, and we use them in 1⁄4" two-con- ductor (TS) and three-conductor (TRS) versions.

phone plug

The male counterpart to the phone jack. See above.

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