Mackie 1640 Auxiliary Section, 35. AUX 1 -6MASTERS, 36. AUX PRE/POST, SENDS, glorious sound, Aux “Pre vs. Post”, Signal Flow Diagram, down, but that never happens.)

Auxiliary Section

This section includes the AUX MASTERS (Sends) and the AUX RETURNS. These can be a bit confusing to the uninitiated, so here’s the whole idea behind aux sends and returns: sends are outputs and returns are inputs. AUX SENDs tap signals off the channels, via the AUX knobs [11], mix these signals together, then send them out the AUX SEND jacks [62].

These outputs are fed to the inputs of an external processor like a reverb or digital delay. From there, the outputs of this external device are fed back to the mixer’s AUX RETURN jacks [61]. Then these signals are sent through the AUX RETURN level controls [38], and finally delivered to the MAIN MIX [46].

So, the original “dry” signals go from the channels to the MAIN MIX and the affected “wet” signals go from the AUX RETURNS to the MAIN MIX, and once mixed together, the dry and wet signals combine to create a

(pre-fader) or after the fader (post-fader). Typically, you use a pre-fader send for monitors so you can control the monitor levels independently from the MAIN MIX. Use a post-fader send for effects, so that the “wet” signal level follows the “dry” signal level.

Most other mixing consoles require you to assign the pre/post function in pairs (Aux 1/2, Aux 3/4), which can be very limiting if you want to provide three monitor sends and one effects send, for example. The Onyx 1640 allows you to assign the pre/post function for each AUX SEND individually!

Both pre- and post-fader sends are affected by the MUTE button and the EQ controls (unless the EQ is bypassed, of course).

AUX MASTERS

AUX	AUX	EFX
SENDS	RETURNS	TO
		MON

Manual s’Owner

glorious sound!

The AUX SENDS can also be used to provide another mix for stage monitors, for example. In this case, the AUX RETURNS aren’t used to return the signal. Instead, they can be used as additional stereo inputs.

35. AUX 1 -6 MASTERS

1

	MON
OO	+15

2

MON

OO +15

PRE

POST

SOLO

PRE

POST

SOLO

1

OO +10 OO +10

TO AUX 5

2

OO +10 OO +10

TO AUX 6

The AUX MASTERS provide overall control over the AUX SEND levels, just before they are delivered to the AUX SEND outputs [62]. These knobs go from off (∞) to +15 dB when turned all the way up.

This is usually the knob you turn up when the lead singer glares at you, points at his stage monitor, and sticks his thumb up in the air. (It would follow that if the singer stuck his thumb down, you’d turn the knob

PRE

POST

	3			3
	MON			+10	SEND
OO	+15	SOLO	OO
					TO
		PRE
	4	POST		4	MAINSUBS
	MON
OO	+15	SOLO	OO	+10

down, but that never happens.)

36. AUX PRE/POST

The PRE/POST switches determine whether the AUX SEND signal is tapped from the channel before the fader

5

MON

OO +15

6

	MON
OO	+15

PRE

POST

SOLO	CR/	SUBS
	PHONES	1-2
	ONLY	3-4

PRE

POST

SOLO

FADER

ASSIGN

PAN

INPUT GAIN LOW CUT INSERT EQ		MAIN MIX
EQ	MUTE
IN/OUT
		SUB 1-2
		SUB 3-4	MASTER SECTION
		AUX SEND 1	AUX SEND 1 MASTER
			TO AUX SEND 1
		"POST" SIGNAL	OUTPUT
	"PRE" SIGNAL		AUX SEND 1 PRE/POST SWITCH
Aux “Pre vs. Post”		AUX SEND 2	AUX SEND 2 MASTER
Signal Flow Diagram
			TO AUX SEND 2
			OUTPUT
			AUX SEND 2 PRE/POST SWITCH

Owner’s Manual 17