Always be sure to perform the Level-Setting Procedure when connecting to LINE inputs that have TRIM controls, and check the level and adjust it externally on the stereo inputs without TRIMs.

To connect balanced sources to the line-level inputs, use a 1/4" tip-ring-sleeve (TRS) plug, the type

MIXER ANATOMY: CHAPTER 2

sound, but the guitar will lose punch and treble. The proper way to connect an instrument pickup directly to a Mackie mixer is to use a Direct Box (or DI =Di- rect Injection) between the guitar and a MIC input.

Hi-Z Guitar Inputs

found on some stereo headphones:

RING SLEEVE

SLEEVE RING TIP

TIP

RING

TIP

SLEEVE

To connect unbalanced line-level sources, use a cable with 1/4" mono (TS) plugs. In music store lingo, that’s an “instrument cable” or “quarter inch patch cord.” When a TS plug is inserted into a TRS jack, the Ring (low signal) and Sleeve (ground) get connected together.

1

YX MIC

P

ON

 

RE

HI-Z

1

MIC

HI-Z

48V

20 U

30

40

U 60 -20dB +40dB

GAIN

After all that, we decided that it would be a good idea to build a direct instrument input into some of our mixers. On channels 1 and 2 of the Onyx series mixers and 800R preamp, the MIC/HI-Z switch switches the channel input from the XLR mic connector to the 1/4" input jack. This jack provides a high impedance input suitable for directly connecting an instrument pickup, saving you the cost and fuss of using a DI. We’re not stuffy – you can plug your bass in here, too.

See the Mixer Tips section for more information on balanced and unbalanced connections.

The TRIM Control

TRIM

 

1

The TRIM control adjusts the

 

input sensitivity of the MIC or LINE

d

 

-10

BV

 

IC GAI

 

U M

N

 

IN jack, to match the input signal

 

 

 

0

60

 

to the operating range of the mixer.

 

On all Mackie mixing consoles with

+15dB

-45dB

 

 

 

 

the exception of the PPM series,

the TRIM control is located at the top of the channel strip. That makes it easy to find, since TRIM is the first control the signal encounters on its way through the console. The PPM series has an Input Level Set control and LED indicator above each channel’s VOLUME control.

Whenever you connect a new input, or the input source changes (you move the mic from the dulcimer to the kick drum), you should perform the Level-Setting Procedure. That procedure is “how to use the TRIM control.”

Connecting Electronic Instruments

Synthesizers, guitar processors, other

electronic instruments, and computer sound cards work fine when connected to the LINE inputs. The pickups on electric guitars

and basses, even though the plug fits, are a different animal, however. Pickups require a higher input impedance than the Mackie LINE IN provides. Plugging a guitar into a LINE IN jack will probably make some

The Hi-Z jack also serves as a line input jack (it has the same gain as the line inputs on the other channels). When using line inputs with channels 1 and 2, don’t forget to push the “Guitar” button.

Tape Returns (8-Bus Only)

The TAPE RETURN jacks on the rear panel of the 8-Bus console are for connecting the outputs of a multitrack recorder.

15

13

11

9

OPERATING

LEVEL CH. 9-16

IN –10dBV

OUT +4dBu

16

14

12

10

+4 / –10 BALANCED / UNBALANCED

TAPE RETURNS 9-16

These are balanced 1/4" TRS jacks which will also accommodate unbalanced connections. They’re grouped in sets of eight, with each group having an OPERATING LEVEL switch to properly match the gain of these inputs to pro (+4 dBu) or semi-pro (-10 dBV) recorders.

TAPE RETURN jacks can be routed to either the channel (for mixing) or Mix-B (during tracking). Their fate is determined by the FLIP and MIX-B SOURCE switches.

Tape Inputs

These unbalanced RCA TAPE INPUT jacks are designed to work with semi-pro as well as pro record- ers. The provide an unbalanced input at 0 dBu. Connect your 2-track tape recorder’s outputs here, using standard RCA cables.

 

 

Compact Mixer Reference Guide

19