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Surround Processor/Receiver Set-Up

Digital surround sound receivers, preamps or processors must be configured properly to get the best performance from your speakers. This involves telling the surround processor where to send each channel's bass information. This is known as bass management. Most processors and receivers allow you to adjust these functions using an on-screen display. Check the user's manual of your electronics to learn how to access these functions.

The good news is that once you've selected the bass management mode that you're happy with, you can forget about it and just enjoy your system. The bad news is that bass management may be confusing at first. Take your time, read this section, and then experiment.

The bass management nomenclature and functions of Dolby Pro Logic are different than those of Dolby Digital. We will cover Dolby Digital setup first.

Dolby Digital and DTS Surround

When a channel is selected as "Large" it means the bass information for that channel, sound below 80 Hz, will be directed to that speaker along with all the other frequencies. When "Small" is selected, the bass is filtered out of that speaker and directed to either the subwoofer output jack or to the left and right channels (depending on whether the subwoofer is selected as "on" or "off"). For example, if you select the center channel speaker as "Large," the center channel bass will go to the center speaker. If you select "Small," the center bass will go elsewhere.

Subwoofer
- If you have connected your subwoofer to the subwoofer output jack, select subwoofer as "On." The subwoofer will now play the Low Frequency Effects bass channel and the bass of any other speakers in the system selected as "Small." If your subwoofer is connected to the system in any other way (such as L&R pre-outs or L&R speaker outputs), select subwoofer as "Off." LFE and bass from channels selected as small will now go to the left and right front channels.
Left and Right Front Speakers
- Sometimes the choice between "Small" and "Large" is not so clear-cut. These are the tradeoffs: When the main speakers are set to "Small" you will be increasing the top volume capability of those speakers and probably lowering their distortion as well. Experiment and see what works best for you. Here are some speaker set-up suggestions:
Floorstanding
- If your main front speakers are floorstanding models with good bass response, select "Large." If your subwoofer is connected to the subwoofer output jack and you wish to limit the bass response of your main speakers for the sake of higher volume, select "Small."
Bookshelf
- Choose "Small" unless you are not using a subwoofer anywhere in the system, in which case choose "Large."
Palm-sized satellite/subwoofer systems
- If the subwoofer is hooked up to the front left and right speaker or preamp outputs (recommended), select "Large." If the subwoofer is hooked up to the subwoofer output jack (generally not recommended), select "Small."
Center Speaker
- Very few center channel speakers can produce as much bass as a subwoofer or most main speakers. Unless you have a truly full-range (big) center speaker, set the center speaker as "Small."
Surround Speakers
- If you are using bookshelf, on-wall or in-wall speakers as surrounds, select "Small." If you have large floor-standing speakers with good bass response, or have a second subwoofer for the surround channels (a bass freak, eh?), select "Large."
Time Delay
- Dolby Digital processors have a "set speaker distance," or time delay function, that ensures that all channel sounds reach your ears at the correct time to aid proper imaging and localization. In most units this is accomplished by simply selecting the distance from your listening position to each speaker via an on-screen display. In other units you must select the amount of delay in milliseconds. Consult your owner?s manual for specific instructions. On most receivers, once this adjustment is set, you can forget about it.

Dolby Pro Logic

If you only have a Pro Logic processor, your set up job is a lot easier (but you won't be getting 5.1 discrete digital channels, of course).

Left and Right Front Speakers
- Not adjustable, always full-range output.
Center Speaker
- Selectable between "Normal," "Phantom," and "Wide." If you have no center speaker, select "Phantom." For almost all center speakers, select "Normal." If you have a large center speaker with good bass response and high power handling, select "Wide."
Surround Speakers
- Not adjustable, always filtered output.

Balancing Act

Once your speakers have been properly installed, consult your receiver or processor's owner's manual for instructions on balancing the output levels for all channels. Sitting in your normal listening position, engage the test tone on your receiver. and adjust the level until each channel produces identical volume.

We strongly recommend using a Sound Pressure Level (SPL) meter to set your channel balance. There is a good one available online from Amazon.com made by the Nady company. Getting the channel balance within 1 dB accuracy (something that's hard to do by ear) makes an enormous difference in the quality of surround sound. An SPL meter is worth every penny of its modest cost.

Many receivers today come with automatic microphone setups. These works well for setting relative level and distances out of the box, but it is important to double check the settings since nothing is as accurate as your ears. Also, we recommend using a camera tripod to mount the microphone near your ear height at the listening position. Please do not simply lay the microphone or SPL meter on the couch- or worse, on the floor. In certain products such as the SurroundBar family, we do not recommend the use of the automatic microhone setup.

It is always best to start out with balance set by SPL meter or the automatic setup, but don't be afraid to make minor level corrections by ear. If the dialog seems unclear on a given movie, boost the output by a dB or two. Likewise, if the surround speakers are calling too much attention to themselves, turn them down a bit. But resist the temptation to over-fiddle with the levels. Instead, just sit back and enjoy the movie!

This article was last modified Apr 16, 2014

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