Mackie SR244 / SR324 Owner's Manual - Page 18

Layout and Function MIC GA-1IN0 U TRIM 2 10 60 +10dB -40dB TRIM CONTROL The white knob at the top of the channel strip is the TRIM con- U AUX trol [8]. TRIM sets the gain 1 (volume level) of PRE the SR24•4 input OO OO +15 amplifier, and is U labeled with gain 2 sensitivity mark- PRE ings for both +15 LINE (the outer U circle) and MIC inputs (the inner circle marked MIC GAIN). Proper setting of the TRIM control is essential for good noise and headroom performance. Since you might be using your SR24•4 to mix dynamic or condenser microphones, elec- tronic keyboards or even guitar amplifier heads, the signals connected to the channel inputs could vary from extremely small to very large. With the TRIM level adjusted correctly, the Mackie input amplifier can accept a wide range of input levels. See Setting Levels With Solo just above, and Important Sensitivity Adjustment Procedure! in the Introduction. EQ SECTION Channels 1-20 (1-28 on the SR32•4) each have a three-band EQ (Equalizer) plus a switchable LOW CUT filter. When any HI, MID or LOW EQ knob is set at its Unity Gain "U" detent, it does not affect the signal. +15 HI EQ +10 +5 The HI 0 section [9] is -5 a fixed 12kHz -10 shelving EQ -15 with ±15dB of 20Hz 100Hz 1kHz 10kHz 20kHz equalization available. This is a great treble control, with the same range as the HI EQ in the Mackie 8•Bus console. Shelving equalizers work on a very broad range of frequencies and consequently are very "musical." In a 12kHz shelf like this section, that means that all the upper harmonics of a sound are raised evenly, basically keeping their original musical relationship to each other. A highfrequency shelving EQ is great for putting shimmer into acoustic guitar and piano tracks or sizzle into vocals and recordings of eggs frying. MID EQ The MID section [10] is a sweepable peak- ing/dipping EQ with a fixed bandwidth of 1.5 octaves (Q=0.9). The FREQ knob sweeps the EQ over a range from 100Hz to 8kHz, and the MID knob selects up to ±15dB of equalization. +15 It's true you +10 can't get along +5 very well with- 0 out high or low -5 EQ, but mid- -10 range EQ often -15 seems to be +15 the most pow- +10 erful. Much of +5 the essential 0 character of a -5 voice or in- -10 strument is -15 20Hz 100Hz 1kHz 10kHz 20kHz determined by U EQ HI 12k -15 +15 U -15 +15 MID FREQ 100 8kHz U -15 +15 LOW CUT 75 Hz 18dB/OCT LOW 80Hz 16