Guided Tour - Channel1: Level (white) - This knob determines the final signal level being sent by achannel to the main speaker outputs. In practice, this will be used to adjust thelevels of the various signals being blended together by the SD8. The “0”position indicates unity gain (no level attenuation or boost). Turning the Levelcontrol clockwise from the “0” position (towards the “10” position) causes thesignal to be boosted by as much as 10 dB. Turning it counterclockwise from “0”(towards the “∞” position) causes the signal to be attenuated (when fullycounterclockwise, the signal is attenuated infinitely—in other words, there isno sound). For best signal-to-noise ratio, all channel level controls should bekept at or near the 0 level.2: Aux 1 / Monitor (violet) - This knob allows you to send signal from one ormore channels to the SD8’s monophonic Monitor output or to an external deviceconnected to the Aux Send 1 output jack on the rear panel. This send ispre-fade; that is, the level of the signal is determined solely by the channel’sinput Trim (see #4 below), and is unaffected by its EQ settings and the positionof its Level control. At the “0” position, the signal is routed with unity gain (thatis, no boost or attenuation). As each Aux 1 / Monitor knob is turned clockwisefrom the “0” position (towards the “10” position), the signal is boosted by asmuch as 10 dB; as it is turned counterclockwise from the 0 position (towardsthe “∞” position), the signal is attenuated. When turned fully counterclockwise,the signal is attenuated infinitely—in other words, no signal is routed. For moreinformation, see the “Using Aux Sends and Returns” section on page 19 of thismanual.3: DSP / Aux 2 (violet) - This knob allows you to send signal from one or morechannels to the SD8’s internal Zoom Digital Signal Processor (DSP) or to anexternal device connected to the Aux Send 2 output jack on the rear panel.This effects send is post-fade; that is, the level of the signal is determined bythe channel’s input Trim (see #4 below), its EQ settings (see #6 below), and theposition of its Level control. At the 12 o’clock position, there is no signal routed.As the DSP / Aux 2 knob is turned clockwise (towards “Aux 2”), signal is routedincreasingly to Aux Send 2. As the DSP / Aux 2 knob is turned counterclock-wise (towards “DSP”), signal is routed increasingly to the internal Zoom DigitalSignal Processor. For more information, see the “Using Aux Sends andReturns” section on page 19 of this manual and the “Using the Internal DSP”section on page 20 of this manual.4: Trim (black) - This knob allows you to set the input gain of the connectedmic or line signal over an exceptionally wide range. Continuously adjustablefrom -6 dB to -50 dB, the input gain is raised when the Trim knob is turnedclockwise and attenuated when it is turned counterclockwise. For informationon how to use this, see the “Setting The Correct Gain Structure” on page 13 inthis manual.5: Peak LED (red) - This warning light indicates an overload situation. It lightswhenever a channel’s signal is 5 dB short of clipping. To stop it from lighting(and to eliminate the accompanying sonic distortion), turn down the channel’sinput Trim knob (see #4 above) or reduce the amount of equalization boost (see#6 on the next page).55LINEMICPEAKCHANNEL 1+10O∞ HIGH+15O-15LEVEL+10O∞MID+12O-12-6 -50TRIM-20LOW+15O-15DSP AUX2L RPANAUX1/MON123468 79