Mackie HD1221 Appendix B: Connections, “XLR” Connectors, Daisy-ChainingMULTIPLE HD1221s, XLR

Appendix B: Connections

Owner’s

“XLR” Connectors

The HD1221 has one female XLR input that accepts a balanced line-level signal. When connecting a balanced signal, be sure it’s wired per AES (Audio Engineering Society) standards:

Balanced XLR Connectors

XLR

Pin 1 – Shield (Ground) Pin 2 – Hot (+)

Pin 3 – Cold (–)

There is also a male XLR connector on the HD1221 labeled LOOP OUT. This is also wired according to the AES standards listed above.

The LOOP OUT connector allows you to connect several HD1221s. Simply plug the signal source

(i.e., mixer output) into the input jack, and patch that speaker’s LOOP OUT jack to the next speaker’s input jack, and so on, daisy-chaining multiple speakers. See below for a visual example of daisy-chaining.

There is a limit to how many HD1221s may

be daisy-chained together. A general rule

is to maintain a load impedance ten times

or more than the source impedance to prevent excessive loading on the source. For example, if the mixer has an output impedance of 120 , then you can daisy chain up to nine HD1221s. This is a load of 1222 (HD1221 input impedance=11 k; 9 of these in parallel=1222 ). Since microphones typically have a higher output impedance, you should limit daisy-chaining from a mic source to two HD1221s.

The LOOP OUT jack is wired straight from the main input connector — there is no electronic circuitry between — so the signal coming out of the LOOP OUT jack is exactly the same as the signal going in.

Manual

to next speaker

L	HD1221		L	HD1221		PARALLEL	HD1221		PARALLEL	HD1221
LOOP	2-WAY HIGH DEFINITION POWERED LOUDSPEAKER		LOOP	2-WAY HIGH DEFINITION POWERED LOUDSPEAKER		MAIN	LOOP 2-WAY HIGH DEFINITION POWERED LOUDSPEAKER		MAIN	LOOP 2-WAY HIGH DEFINITION POWERED LOUDSPEAKER
OUT			OUT			INPUT	OUT		INPUT	OUT
	VOICING MODE	POWER		VOICING MODE	POWER		VOICING MODE	POWER		VOICING MODE	POWER
		LIGHT ON			LIGHT ON			LIGHT ON			LIGHT ON
		+			+			+			+
		LEVEL			LEVEL			LEVEL			LEVEL

L/R

MAIN

OUT

POWER	POWER	POWER	POWER
ON	ON	ON	ON
REVISION	REVISION	REVISION	REVISION
		Mixing Console
		(Mackie 1604-VLZ3 shown)

Daisy-Chaining MULTIPLE HD1221s

Owner’s Manual