Mackie SR244 / SR324 Owner's Manual - Page 42

Appendices doesn't clip until +28dBu (balanced). Even pegging the meters hard, you still have around 12dB of headroom for your peaks. But, if your music is sounding good, don't worry if you're in the yellow a lot or if some parts of the track hardly read at all. You'll quickly get a feel for what works for you, when you can get away with really smacking the tape or the electronics too much. BUSES More often then not, the goal in a mixing console is to mix two or more inputs into one output. Like a coach who has two or more players to get to the same ballgame, console designers use a bus. Even Webster's Unabridged Dictionary agrees, defining the word bus in electronics as "a conductor serving as a common connector for three or more circuits." The Mackie SR24•4 has 15 audio buses. The four suggested in the name (SUBs 1-4) are important, but there are also the main LEFT and RIGHT buses, six AUX buses and three SOLO buses. We will try to be clear just what bus we are talking about when we do talk about buses. SENDS AND RETURNS Sends are buses fed to outputs, and returns are inputs. So why don't we call them outputs and inputs? Well, actually, the terms send and return can mean many things, but the way they are generally used in mixing console parlance is to refer to send buses, which tap off a little of a signal to send to some effects device (like a reverberation unit), and return inputs, which function to return that reverb back into the mix. Sends are also used to tap some mix of signal from a collection of channels for a headphone cue mix. For that matter, sends can be used as additional mix buses, if needed. In the same way, if you don't need them for reverb or effects, returns can be used as additional line-level inputs to your mix. Incidentally, the terms send and return also apply to insert jacks. The only difference is that they process the entire signal, not just tap a little bit of it. SOLO Solo is a standard console function which allows you to listen to one or more sources all by themselves (soloed). You can check EQ, possible distortion or buzz, or just listen to see if a particular mic is open or not. When soloing more than one source, you can listen to the blend of just part of your mix: only the sopranos, for example, or just the tom mics on the drums. The solo circuits are designed not to interrupt the recording process. The solo bus signal is sent directly to the control room monitors without affecting any of the inputs, outputs or recording buses. EQUALIZATION Everybody knows what EQ is, but just in case you'd like a refresher, we'll put a few paragraphs in here. 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 add or subtract level at certain frequencies for a pleasing effect. 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 would look 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. Graphic equalizers have enough frequency slider controls to form a graph of the EQ right on the front panel. Parametric EQs let you vary several EQ parameters at once. And a filter is simply a form of equalizer which allows certain frequencies through unmolested and other frequencies reduced or not at all. Passport, please? The equalizers on the SR24•4 use four different types of EQ in various places. The LOW and HI sections of the EQ are shelving equalizers, with a family of curves shown at right. As you can see, shelving EQs lift or lower the entire range of frequencies above or below a certain point. Most tone controls on home stereos are shelving EQs, often set at 100Hz for the bass and 10kHz for the treble. The LOW EQ on the SR24•4 is at 40