Mackie CR1604 - VLZ Output Section Description, Vlz Mix Architecture, Subgroup Faders, and TAPE

OUTPUT SECTION DESCRIPTION

						You’ve just learned about the
				TM		input channels and how the sig-
CR1604-VLZ					12V
					0.5A	nals get in and out. The signals
16-CHANNEL MIC/LINE MIXER					LAMP
						come in via MIC and LINE input
	U		U	U		jacks, are manipulated by the
1		1		1	TO AUX
					SEND 1	channels, and then sent to the
OO	+10	OO	+20	OO	+15 EFFECTS TO
	U		U	U	MONITORS	output section. In the output
					TO AUX
2		2		2		section, things get a bit more
					SEND 2
OO	+10	OO	+20	OO	+15
						complicated, so put on your
AUX
SENDS			U	ASSIGN OPTIONS		thinking caps.
1		3
SOLO			+20	MAIN MIX	1–2	MAIN L-R MIX FADER
		OO		TO SUBS	3–4
2			U
SOLO		4				As the name implies, this
		OO	+20	C-R / PHNS	RETURNS
PHAN	PWR			ONLY	SOLO	fader controls the levels of
			STEREO AUX RETURNS
			U		LEFT RIGHT	signals sent to the MAIN OUT
				CLIP	0 dB=0 dBu	1	and TAPE
				28		/4" TRS jacks
OO	MAX	OO	+20	10		OUTPUT RCA jacks		. All
C-R / PHONES		TAPE IN		7
						channels and AUX RETURNs
				4
TAPE		TAPE TO		2		that are assigned to the MAIN
		MAIN MIX		0
						L-R MIX, not muted and not
SUBS 1–2				2
						turned fully down will appear
				4
		OO	MAX	LEVEL 7
						at the MAIN OUT. Before the
SUBS 3–4		SOLO		SET
				10
				20		main mix gets to this fader, the
MAIN MIX		MODE
				30		signals pass through the MAIN
SOURCE		NORMAL (AFL)		RUDE
		LEVEL SET (PFL)		SOLO
				LIGHT		INSERT .
	ASSIGN TO MAIN MIX
						The MAIN L-R MIX signals
LEFT		LEFT	LEFT	LEFT		are off with the fader fully
					PHONES	down, the “U” marking is unity
RIGHT		RIGHT	RIGHT	RIGHT	MAIN
						gain, and fully up provides
1		2	3	4
					L-R MIX
				dB	dB	10dB additional gain. This ad-
				10	10
				5	5	ditional gain will typically
				U	U	never be needed, but once
				5	5	again, it’s nice to know it’s
				10	10	there. The fader itself is a ste-
				20	20	reo version of the channel and
				30	30	subgroup faders — same su-
				40	40	persmooth custom taper, same
				50	50
				60	60	dead silence when turned fully
				OO	OO
						down. This is the fader to pull
						down at the end of the song
				when you want “The Great Fade-Out.”

VLZ MIX

ARCHITECTURE

When designing a mixing

circuit, the lowest noise and best crosstalk specs are

achieved by using Very Low Impedance (VLZ). To implement VLZ in a mixer, the power supply must be able to deliver plenty of current to the circuitry. That’s why those “wall wart” mixers are often noisy — they can’t power a VLZ circuit.

At Mackie, audio quality is much more im- portant than the price of wall warts. All of our mixers now employ VLZ and built-in power supplies that deliver more than enough cur- rent, resulting in sonic specifications that rival consoles upwards of $50,000!

SUBGROUP FADERS

As you might expect, these faders control the levels of signals sent to the SUB OUTS. All chan- nels that are assigned to subgroups, not muted and not turned fully down will appear at the SUB OUTS. Unlike the MAIN OUT, the sub- group signals do not pass through an insert jack on their way to the subgroup faders. That’s no problem — should you want to send these sig- nals through a serial effects processor, simply patch from the SUB OUTS to the effect’s input, and from the effect’s output to whatever the fi- nal destination is, usually a multitrack recorder.

The subgroup signals is off when its fader is fully down, the “U” marking is unity gain, and fully up provides 10dB additional gain. Re- member that if you’re treating two subgroups as a stereo pair, subgroup 1 and 2 for example, make sure that both subgroup faders “ride” together, to maintain the left/right balance.

ASSIGN TO MAIN MIX

One popular use of the subgroups is to use them as master faders for a group of channels on their way to the MAIN L-R MIX. Let’s say you’ve got a drum kit hogging up seven channels and you’re going to want to fade them out at a different rate than the other channels. You don’t want to try that with seven hands or seven fin- gers, so just un-assign these channels from L–R, reassign them to subgroup 1–2, engage the AS- SIGN TO MAIN MIX, LEFT on subgroup 1 and the ASSIGN TO MAIN MIX, RIGHT on subgroup 2. Now you can ride the entire stereo drum mix with two faders — 1 and 2.

If you engage just one ASSIGN TO MAIN MIX switch per subgroup (LEFT or RIGHT), the signal sent to the MAIN L-R MIX will be the same level as the SUB OUTS. If you want the subgroup to appear in the center of the main mix, engage both the ASSIGN TO MAIN MIX, LEFT and ASSIGN TO MAIN MIX, RIGHT switches. The signal will be sent to both sides, and will be attenuated just enough to pre- serve constant loudness , just like the channel PAN knobs when set center.

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