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                        4-Channel Line Mixer with FireWire
O W N E R ’ S M A N U A L
1 2 3 4
LEVEL LEVEL
SET SET
U U U U
GAIN GAIN
POWER
-14 +14 -14 +14 -14 +14 -14 +14
U U U U
EQ EQ
HIGH HIGH
L R
OL
KILL +10 KILL +10 KILL +10 KILL +10
10
U U U U
7
MID MID
4
0
KILL +10 KILL +10 KILL +10 KILL +10
U U 4 U U
10
LOW LOW
20
KILL +10 KILL +10 KILL +10 KILL +10
AUX AUX
MAX MAX
MAX MAX MAX MAX
FW IN PHONES
U U U U
LEVEL LEVEL
LOOP
OUT
MAX MAX MAX MAX
MAX
OO
OO OO OO OO
OO OO OO OO
OO OO                                         
                    
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                        Important	 Safety	 Instructions 12.Use 	 	 only	 with	 a	 cart,	 stand,	 tripod,	 bracket,	 or	 table	 specified	 by	 the	 1.	 Read 	 these	 instructions.		 manufacturer,	 or	 sold	 with	 the	 apparatus.	 When	 a	 cart	 is	 used,	 use	 2.	 Keep 	 these	 instructions. caution	 when	 moving	 the	 cart/apparatus	 combination	 to	 avoid	 injury	 from	 tip-over. 3.	 Heed 	 all	 warnings. 13.Unplug 	 	 this	 apparatus	 during	 lightning	 storms	 or	 when	 unused	 for	 long	 4.	 Follow 	 all	 instructi
                    
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                        Owner’s Manual Contents IMPORTANT	 SAFETY	 INSTRUCTIONS	 ........................ 2 TOP	 PANEL	 FEATURES	 ........................................... 12 INTRODUCTION	 ...................................................... 4 CHANNEL	 CONTROLS	..................................... 12 FEATURES	............................................................... 4 10.	 LEVEL	 SET	 LED	 ......................................... 12 GETTING	 STARTED	................................................... 5 11.	
                    
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                        FEATURES Introduction • 4 stereo line-level input channels. Thank you for choosing a Mackie U.420 mixer. It • Built-in FireWire 2x2 interface provides easy  contains all your favorite features in a ultra-compact input from computer to the main mix, and easy  4-channel line mixer, along with a built-in FireWire outputs to the computer from the main mix. It  interface, and a phono input for turntablists. has 24-bit resolution, and 44.1, 48, 88.2, and 96  kHz sample rates. The U.420 is equally at h
                    
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                        Owner’s Manual Set	 the	 Levels Getting	 Started To set the gain controls, it’s not even necessary to  hear what you’re doing at the outputs of the mixer. If  READ	 THIS	 PAGE!! you want to listen while you work, plug headphones into  the phones jack on the front panel, then set the phones  Even if you never read manuals, please  knob up a little. read and digest the safety instructions  on page 2, and this page before you  1. Play something into the selected input. Be sure  begin using your mix
                    
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                        Hookup	 Diagrams HR824 Powered Monitors Drum machine Effects/ Sampler Headphones MAIN AUX L OUT OUT L L (MONO) L (MONO) L (MONO) 4 3 2 1 (MONO) GND PHONO L POWER 18V,1.5A R R R R R R ground wire Laptop Keyboard Turntable with phono-level out This diagram shows a stereo synth, and a drum machine connected to channels 1 & 2, and a turntable  connected to the phono inputs of channel 4. The stereo aux output sends signals to the effects/sampler,  and the wet signal is returned into channel 3. The ma
                    
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                        Owner’s Manual SRM450 Powered Speakers Guitar SRM450 Powered Drum machine Stage Monitor Headphones MAIN AUX L L L L L OUT OUT (MONO) (MONO) (MONO) (MONO) 4 3 2 1 GND PHONO L POWER 18V,1.5A R R R R R R ground wire Laptop Keyboard Turntable with phono-level out This diagram shows a guitar connected to channel 1, plus a stereo synth and drum machine connected  to channels 2 & 3. A turntable is connected to the phono inputs on channel 4. Use the left aux send to  connect to a Mackie SRM450 for stage
                    
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                        Personal Stereo Monitors (SRM150 powered monitors) This diagram shows an acoustic  Acoustic guitar connected to channel 1, plus  Guitar a stereo performance synth like a  Nord Lead on channel 2, a good  Main Mix organ like a Korg CX-3 on chan- to front-of-house Electronic Piano nel 3, and an electronic piano on  mixer channel 4 (with a dab of chanel #5  behind each ear for good measure).   The main outputs are fed to the  FOH (front of house) mixer for the  MAIN AUX L OUT OUT L L (MONO) L (MONO)
                    
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                        Owner’s Manual Digital Video Camcorder HR824 Powered Monitors Headphones MAIN AUX L L L (MONO) L (MONO) L (MONO) OUT OUT (MONO) 4 3 2 1 GND PHONO L POWER 18V,1.5A R R R R R R Video out DV Recorder 1 TM Video out iPod Docking Station Desktop computer and large display DV Recorder 2 Video Monitor This diagram shows a DV camcorder audio connected to channel 1, DVR decks connected to channels  2 and 3, and an iPod docking station connected to channel 4. The main outputs are fed to a pair of Mackie H
                    
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                        Rear	 Panel	 Features MAIN AUX L L L L L OUT OUT (MONO) (MONO) (MONO) (MONO) 4 3 2 1 GND PHONO L POWER 18V,1.5A R R R R R R 1. INSTRUMENT/LINE Input . PHONO Inputs These inputs accept either 1/4" TRS balanced or TS Channel 4’s RCA jacks accept stereo phono-level  unbalanced connectors. signals from turntables. Check that your turntable has  a phono-level output and a moving-magnet cartridge.  Unlike the other inputs, channel 1’s left input can  Turntables usually have a ground wire that needs t
                    
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                        Owner’s Manual If you plug a cable into the left aux output Warning: The headphone amp is designed to  jack, and leave the right output jack empty, drive any standard headphones to a very loud  the right and left signals are summed together level. We’re not kidding! It can cause perma- to provide a mono output. nent hearing damage. Even intermediate levels may be  painfully loud with some headphones. Be careful!  The stereo aux output from these connectors is the  sum of all channels whose aux l
                    
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                        Top	 Panel	 Features 1 2 3 4 LEVEL LEVEL SET SET U U U U GAIN GAIN POWER -14 +14 -14 +14 -14 +14 -14 +14 U U U U EQ EQ HIGH HIGH L R OL KILL +10 KILL +10 KILL +10 KILL +10 10 U U U U 7 MID MID 4 0 KILL +10 KILL +10 KILL +10 KILL +10 U U U 4 U 10 LOW LOW 20 KILL +10 KILL +10 KILL +10 KILL +10 AUX AUX MAX MAX MAX MAX MAX MAX FW IN PHONES U U U U LEVEL LEVEL LOOP OUT MAX MAX MAX MAX MAX When this switch is out, input 1 is a line-level input,  Channel	 Controls just like inputs 2–4. You can connect 
                    
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                        Owner’s Manual -BAND EQ 1. AUX The U.420 has 3-band equalization at carefully These stereo controls allow you to adjust how much of  selected points — low shelving at 300 Hz, mid peaking the channel signal is added to the aux bus. The aux bus  at 1 kHz, and high shelving at 4 kHz. “Shelving” means contains the sum of all channels whose aux controls are  that the circuitry boosts or cuts all frequencies past the set to more than minimum. specified fr equency. For example, rotating the low EQ  T
                    
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                        1 2 3 4 LEVEL LEVEL SET SET U U U U GAIN GAIN POWER -14 +14 -14 +14 -14 +14 -14 +14 U U U U EQ EQ HIGH HIGH L R OL KILL +10 KILL +10 KILL +10 KILL +10 10 U U U U 7 MID MID 4 0 KILL +10 KILL +10 KILL +10 KILL +10 U U U 4 U 10 LOW LOW 20 KILL +10 KILL +10 KILL +10 KILL +10 AUX AUX MAX MAX MAX MAX MAX MAX FW IN PHONES U U U U LEVEL LEVEL LOOP OUT MAX MAX MAX MAX MAX Control	 Section 18. POWER LED 0. FW IN This will light whenever the external power supply is  This control lets you adjust the signa
                    
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                        Owner’s Manual 1. FW LOOP OUT . MAIN LEVEL In addition to a mix of channels 1 to 4, the FireWire This big handy knob adjusts the main mix output level  output to the computer can contain any FireWire input, at the main outputs [6]. Use it wisely to turn up the  if this switch is down. (The mains and phones are not tunes in your main speakers, or to turn it down when- affected by the switch, and always provide a full mix of ever you think the room could benefit from a little less  1 2 3 4 chan
                    
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                        Appendix	 A:	 Service	 Information If you think your U.420 has a problem, please check • If you are playing a guitar into channel 2, 3, or 4,  out the following troubleshooting tips and do your best you need to use a DI box for the correct impedance  to confirm the problem. Visit the Support section of our match and high frequency fidelity. website (www.mackie.com/support) where you will find  • Try the same source signal in another channel, set  lots of useful information such as FAQs, document
                    
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                        Owner’s Manual Repair For warranty repair or replacement, refer to the war- ranty information on page 27. Non-warranty repair for Mackie products is available  at a factory-authorized service center. To locate your  nearest service center, visit www.mackie.com, click  “Support” and select “Locate a Service Center.” Service  for Mackie products living outside the United States can  be obtained through local dealers or distributors. If you do not have access to our website, you can call  our Tech 
                    
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                        Appendix	 B:	 Connections 1/4"	 TRS	 Phone	 Plugs	 and	 Jacks RCA	 Plugs	 and	 Jacks “TRS” stands for Tip-Ring-Sleeve, the three connection RCA-type plugs (also known as phono plugs) and jacks  points available on a stereo 1/4" or balanced phone are often used in home stereo and video equipment and  jack or plug. TRS jacks and plugs are used for balanced in many other applications. They are unbalanced and  signals and stereo headphones: electrically equivalent to a 1/4" TS phone plug. SLEEVE TIP
                    
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                        Owner’s Manual Appendix	 C:	 Technical	 Info Specifications Frequency Response (0 Hz to 0 kHz, unity gain) :  Input Impedance:    Line input to any output:  +0/–0.5 dB Line input:  100 k Ω balanced Phono input to any output:  ±0.5 dB of RIAA EQ   Phono input:  47.5 k Ω shunt with 200 pF   curve Maximum Output Levels:    FireWire output to FireWire input     Main out:  +15 dBu (with loop out switch engaged): +0/–0.5 dB  Aux out:  +15 dBu Distortion (THD+N):    Phones:  1.5 Vrms into 32 Ω (70 mW
                    
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                        	 0 U.40 4-Channel Line Mixer U.420 4-Channel Line Mixer Block Diagram Main Out level Channel Main Mix Sum Sum Level Set Main Out L Level L Normal Main Out L Channel 1 3-Band EQ HI-Z LO MID HI L R R HI–Z Level Gain LO MID HI R Phones Main Out R level Aux Level Set FireWire In Phones from Computer Channels 2-3 3-Band EQ Firewire FireWire Out LO MID HI Sum to Computer ADC DAC L L L Gain Level LO MID HI Firewire R In Level R R Ch.1-4 to FW output FireWire input and Ch.1-4 to FW output Aux Out L L