Mackie 1642-VLZ Pro Owner's Manual Glossary - Page 7

as an insert processor (serial) on a particular input or subgroup, or it may be used via the aux send/return system (parallel). See also echo, reverb. EIN Equivalent Input Noise. A specification that helps measure the "quietness" of a gain stage by deriving the equivalent input noise voltage necessary to obtain a given preamp's output noise. Numerically, it's the output noise at a given gain setting minus the gain. EIN is usually measured at maximum gain and typically ranges from -125 to -130 dBm. EMI Electro-Magnetic Interference. This refers to current induced into the signal path as a result of an external magnetic field. In audio systems, this is usually manifested as a 60 Hz or 120 Hz hum or buzz (50 Hz or 100 Hz in 50 Hz systems). The source of this noise can be from a ground loop or from the signal wire coming too close to a strong magnetic field such as a transformer or high-current linecord. EQ Short for equalization. EQ curve A graph of the response of an equalizer, with frequency on the x (horizontal) axis and amplitude (level) on the y (vertical) axis. Equalizer types and effects are often named after the shape of the graphed response curve, such as peak, dip, bell, shelf, or notch. equalization Equalization (EQ) refers to purposefully changing the frequency response of a circuit, sometimes to correct for previous unequal response (hence the term, equalization), and more often to boost or cut the level at certain frequencies for sound enhancement, to remove extraneous sounds, or to create completely new and different sounds. Bass and treble controls on your stereo are EQ; so are the units called parametrics and graphics and notch filters. A lot of how we refer to equalization has to do with what a graph of the frequency response looks like. A flat response (no EQ) is a straight line; a peak looks like a hill, a dip is a valley, a notch is a really skinny valley, and a shelf looks like a plateau (or a shelf). The slope is the grade of the hill on the graph. Aside from the level controls, EQs are probably the second most powerful controls on any mixer (no, the power switch doesn't count!). F fader Another name for an audio level control. Today, the term refers to a straight-line slide control rather than a rotary control. family of curves A composite graph showing on one chart several examples of possible EQ curves for a given equalizer or equalizer section. filter A simple equalizer designed to remove certain ranges of frequencies. A low-cut filter (also called a high-pass filter) attenuates frequencies below its cutoff frequency. There are also highcut (low-pass) filters, bandpass filters, which cut both high and low frequencies but leave a band of frequencies in the middle untouched, and notch filters, which remove a narrow band but leave the high and low frequencies alone. flanging A term for an effect similar in sound to phasing. Before we had electronic delay units, flanging was accomplished by playing two tape machines in synchronization, then delaying one slightly by rubbing a finger on the reel flange. Get it? 7