Mackie Big Knob Owner's Manual - Page 10

BIG KNOB 2-TRACK A Level Switch This two-position switch sets the input level of the 2-TRACK A inputs to either +4 dB (balanced input) or -10 dB (unbalanced input). Use the +4 dB setting for professional equipment operating at the +4 dBu standard, and use the -10 dB setting for consumer equipment operating at the -10 dBV standard. 2-TRACK A Trim Control This control adjusts the input sensitivity of the incoming 2-TRACK A signal by ±10 dB (unity at center detent). This allows for precise level matching between the various incoming 2-track sources, which often do not have output level controls of their own. 2-TRACK B Inputs These stereo 1/4-inch balanced/unbalanced inputs are fed by the outputs of the second external 2-track recorder. If a mono signal is plugged into the LEFT input only, it is automatically routed to both LEFT and RIGHT inputs. 2-TRACK B Level Switch This two-position switch sets the input level of the 2-TRACK B inputs to either +4 dB (balanced) or -10 dB (unbalanced). Use the +4 dB setting for professional equipment operating at the +4 dBu standard, and use the -10 dB setting for consumer equipment operating at the -10 dBV standard. 2-TRACK B Trim Control This control adjusts the input sensitivity of the incoming 2-TRACK B signal by ±10 dB (unity at center detent). This allows for precise level matching between the various incoming 2-track sources, which often do not have output level controls of their own. DAW MIX These stereo 1/4-inch balanced/unbalanced inputs are fed by the master mix output of the DAW, usually the DAW outputs 1-2. If a mono signal is plugged into the LEFT input only, it is automatically routed to both LEFT and RIGHT inputs. DAW MIX Level Switch This two-position switch sets the input level of the DAW MIX inputs to either +4 dB (balanced input) or -10 dB (unbalanced input). Use the +4 dB setting for professional equipment operating at the +4 dBu standard, and use the -10 dB setting for consumer equipment operating at the -10 dBV standard. DAW MIX Trim Control This control adjusts the input sensitivity of the incoming DAW MIX signal by ±10 dB (unity at center detent). This allows you to precisely fine tune the incoming level of the DAW MIX input so it matches the signal level of other incoming 2-track sources. PHONO These stereo RCA unbalanced inputs are fed by the outputs of a turntable with a moving-magnet cartridge (MM). These inputs have a built-in precision RIAA preamplifier that provides the equalization and gain required for a phono-level signal to return it to a proper line-level signal. This allows you to playback vinyl records and dub them to a 2-track recorder, as well as send the phono signal to the input of the DAW for archiving/ restoration/CD burning. Note: Two RCA shorting plugs are provided, which should be plugged into the PHONO inputs when they are not being used. This terminates the inputs and reduces the noise floor should you accidentally push in the PHONO INPUT SOURCE SELECT button. PHONO Trim Control This trim control adjusts the input sensitivity of the incoming PHONO signal by ±10 dB. This allows you to precisely fine tune the incoming level of the PHONO input so it matches the signal level of other incoming 2-track sources. The PHONO input does not need a +4/-10 level switch since a phonograph is always at a consumer signal level, unlike tape decks and soundcards, which could be -10 or +4, depending on the model. PHONO Grounding Lug (GND) This small grounding lug allows you to connect the grounding wire from an attached turntable. This prevents ground loops and hum from showing up in the phono source's audio signal. DAW PHONES MIX INPUT These stereo 1/4-inch balanced/unbalanced inputs allow connection of a second stereo mix from the DAW for a custom headphone mix. POWER ON A B C MONITOR MONITOR MONITOR OUTPUTS 2-TRACK 2-TRACK A B -10dB +4dB L -10dB +4dB L -10dB +4dB L L +4dB -10dB +4dB -10dB L AC SELECT 100-120V 220-240V R R R R R DAW OUTPUT +4dB -10dB L R PHONES AMP +4dB -10dB L R STUDIO DAW PHONES MIX INPUT -10dB +4dB L L +4dB -10dB 2-TRACK A U -10dB +10dB R R DAW MIX U +4dB -10dB (MONO) L BAL/ UNBAL +4dB -10dB (MONO) L SOURCES 2-TRACK B R U -10dB +10dB PHONO R U BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL BAL/UNBAL -10dB +10dB BAL/ UNBAL -10dB +10dB +4dB -10dB (MONO) L R BAL/ UNBAL GROUND L R TALK BACK FOOT SWITCH RIAA 10 BIG KNOB