Mackie instruction manual Installing the SP400C, Placement, Installation

6. Installing the SP400C

The SP400C can be installed into suspended or drywall-based ceilings. The speaker is secured in place with the four rotating mounting tabs. The support rails are used with suspended ceilings (standard 24" spacing) to transfer the weight of the speaker to the T-channel runners.

2.Insert the C-ring (2) through the hole so the hanging brackets on the C-ring point up. If installing in a suspended ceiling, align the support rails (3) on either side of the hole and hook them onto the T-channel runners in the suspended ceiling support grid. Then slide the C-ring brackets over the support rails as shown in the illustration below.

Placement

There are two considerations when deciding where to place the SP400C speakers.

Location: When installing the speaker in a suspended ceiling with conventional ceiling tiles, the location of the speaker is determined in part by the support grid of the suspended ceiling system.

When installing the speaker in a drywall ceiling, the location of the speaker is determined in part by the location of the ceiling joists.

Coverage: It is important to locate the speakers in such a way that the sound is evenly distributed over the entire area. Keep in mind that the sound has farther to travel on the outside edge of the coverage area for each individual speaker than directly below the speaker, resulting in a decrease in SPL at the outer edges of the listening plane. The SP400C is

–6 dB at an off-axis angle of 55º from 1 kHz to 6 kHz (110º coverage).

The speaker placement should be designed such that the edges of the coverage pattern for each speaker are at least touching. The more overlap that is provided (higher density coverage), the more SPL the system is capable of providing and the less variation in level as you move around the area. The downside of higher density coverage, of course, is that more speakers are required for a given area.

Installation

Note: Observe all local and national codes when installing the SP400C.

1.Cut the hole for the speaker using the supplied cutout template. If using a circular cutter, set the diameter to 10.8 inches (274 mm).

Support Rails

C-Ring

Bracket

Ceiling Tile

T-Channels

3.You can install the SP400C speakers using either conduit or plenum-approved jacketed cable.

A.Installation with Plenum-Approved Jacketed Cable or Flexible Conduit

Note: If you can access the back of the SP400C once it is mounted, you may prefer to do steps A3 and A4 before doing steps A1 and A2.

A1. Attach the speaker cable to the supplied Phoenix-type connector (8). This is a 4-position connector, with two "+" and two "–" terminals. Connect the speaker cable to the "+" and "–" terminals labeled IN. If connecting another speaker in a distributed system (in parallel), connect the speaker cable running to the next speaker to the "+" and "–" terminals labeled

LOOP THRU.

A2.Open the terminal cover plate (7) on the back of the SP400C. Route the speaker cable through the strain relief bracket (9), and connect the

			P
			O
		LO
			THRU
P		IN	+
	IN
O		+
LO	–
THRU–

	1
+
LOOP	2
THRU	+	3
	IN
	–
	IN	4
		–
		LOOP
	THRU

SP400C – 4