Atlantic Technology 642e SB instruction manual Care of Your Subwoofer, Dual Subwoofer Placement

10 Care of Your Subwoofer

Model 642e SB Powered Subwoofer

Dual Subwoofer Placement

When two subwoofers are used,you may wish to place them asymmetri- cally; that is, in slightly different positions in the room (Figure 7). This will reduce common mode room resonances that occur with symmetri- cally positioned subwoofers.You can also try placing the subwoofers in the same corner,if you wish.Experiments have shown this to be a viable means of producing smooth bass response in many rooms.

Figure 7

Asymmetrical arrangement for 2 subwoofers in a home theater, for example, one closer to a corner than the other

Place subwoofers

assymmetrically in room

for smoother bass

Using the Subwoofer LowPass Control

		When used with the complete System 4200e,
LOWPASS
		the 642e SB Low-pass control should be set at
60	80	around 80Hz unless you are using a proces-
		sor with its own built-in crossover. The goal
		is to optimize the performance of the system
		by ensuring that the subwoofer and satellites
		produce a cohesive and well integrated sound
40	140	“picture.” The low-frequency response of the
		System 4200e satellites has been optimized to
work with approximately an 80Hz crossover point.

Higher crossover frequencies pass more bass but can sound boomy and may be more easily localized to the subwoofer. Higher crossover frequencies may be suitable, however, when using very small satellites that have no real low frequency performance. Settings lower than 80Hz should be employed if you are using larger speakers that have extended bass response.This way,the subwoofer will only reproduce the very low- est bass frequencies that are in the range where the large main speakers begin to roll off.

It’s generally undesirable to have the main speakers and the subwoofer overlap too much. Larger speakers means a lower Low-pass crossover frequency, smaller speakers means a higher Low-pass crossover fre- quency. Consult the manufacturer’s specified low frequency response for your main speakers to determine the appropriate Low-pass setting on your subwoofer.In the end,however,a little time spent experimenting will generally result in dramatically better bass response.

The Phase Invert Control

A subwoofer operating out of phase with the rest of the

PHASE system won’t provide optimum low frequency perfor- NORMAL mance.Also, the correct subwoofer phase can enhance room acoustics. Since there is so much variation in the industry regarding phase, a switch that will reverse the

INVERT phase of the subwoofer is provided on the amplifier panel.Listen to a monaural musical source with strong bass content.(For example,you can use the mono switch on an FM tuner

or preamp, or use a Y-connector on the outputs of one of your source components to get a mono signal.)

Experiment with the position of the phase switch to get the smoothest bass.It should be obvious which is the correct setting.In particular,there will be a more integrated transition between the satellites and the sub- woofer when they are properly phased.

A Word About Bass, Center Channel Modes and System Set Up

Many surround processors and receivers feature a“Wide” and“Normal” mode for the center channel speaker.Atlantic Technology recommends that the center channel be operated in the “Normal” mode when using a powered subwoofer. The center channel speaker will sound more dynamic and the intelligibility of the system will generally be improved when in the“Normal” mode.

With discrete digital“5.1,6.1,or 7.1” channel systems (Dolby Digital,DTS, etc.) many controllers provide a Bass Management option,which lets you set the front and rear speakers in a limited bandwidth (Small) or full range (Large) mode.When using a subwoofer with Atlantic Technology speakers we recommend setting such a controller to the Small position for all the speakers in the system.

Care of Your Subwoofer

The 642e SB is constructed from 3/4” Medium Density Fiberboard.MDF is a non-resonant material ideal for speaker system enclosures. To clean the cabinet you may use a soft cloth either dry or slightly dampened with clean water. Be careful not to wet the cabinet or allow any water to enter the cabinet seams.Avoid placing your speakers in direct sunlight or near a source of heat that may, over time, damage the finish.

IMPORTANT: Save Your Boxes! If you can do so, save the carton, packing pieces and plastic bags that came with your subwoofer. They will be useful in case you move or have to ship your sub- woofer for any reason. In any case, save all packing materials until you are certain that the system has suffered no damage in ship- ment. If you find such damage, either visible or internal, contact your dealer immediately for the proper return procedure.