OPERATION
Power On
Plug your speakers�AC cords into a wall outlet. Do not use the outlets on the back of the receiver. Initially set the subwoofer Level Controls ¹ to the �O� position. Turn on your subwoofers by pressing the power buttons rear panel of the speakers. on the
except for patient trial-and-error repositioning of the loudspeakers and listeners. Usually, the practical constraints of a living space and the impracticality of massive acoustical treatment mean that equalization is the only practical solution. Professional sound engineers routinely employ sophisticated measurement systems and equalizers to optimize speakers to the installation.This was never practical for the home audiophile. This is why the Bass Optimization System was created. It enables you to identify the dominant low-frequency response characteristic of your room. Once you know the problem, the Bass Optimization System provides the tools needed to optimize the low-frequency characteristics of the speakers to the room they are in, exactly as the professional sound engineers do it.
Turn on your entire audio system and start a CD or movie soundtrack at a moderate level.
Adjust Gain
Turn both subwoofer Level Controls ¹ up to the �5� position (half way). If no sound emanates from the subwoofers, check the AC-line cords and input cables.Are the connectors on the cables making proper contact? Are the AC plugs connected to �live� receptacles? Have the power buttons been pressed to the �On� position? (Note:The Level Control on the front panel will turn green when the power is on and there is a signal present. After about ten minutes with no audio signal, the indicator will turn red.) Once you have confirmed that the subwoofers are active, proceed by playing a CD, record or cassette. Use a selection that has ample bass information. Set the overall volume control of the preamplifier or stereo to a comfortable level. Adjust the subwoofer Level Controls ¹ until you obtain a pleasing blend of bass. Bass response should not overpower the room but rather be adjusted so there is a harmonious blend across the entire musical range. Many users have a tendency to set subwoofer volume too loud, adhering to the belief that a subwoofer is there to produce lots of bass. This is not entirely true. A subwoofer is there to enhance bass, extending the response of the entire system so the bass can be felt as well as heard. However, overall balance must be maintained or the music will not sound natural. An experienced listener will set the volume of the subwoofer so its impact on bass response is always there but never obtrusive.
Preparations
Before beginning the bass tests, please check the following: � Make sure all three Bass Optimization System controls, , µ and ¸, on both speakers are turned fully clockwise. � Make sure the loudness contour (if any) on your receiver/ processor/preamp is turned off. � Set the tone controls (Bass and Treble) to their center or flat positions. � Bypass all surround and effects features of your receiver/ processor/preamp or set to Stereo Bypass. � If you are using a multichannel surround processor or receiver, make sure all bass-management features are properly set.The Audio channels should all be set to �Small� or �HighPass� and the subwoofer set to �On.� � Set the Bass Optimization System selectors to �On.� For best results, it is recommended that all major furnishings are in place and that all doors and windows in the listening area are in their normal positions.That is, if you normally listen to music with all doors closed, then this is how they should be during this procedure. To solve a problem, it helps to first identify whether you have one and, if so, what it is. First, play a variety of music and films with energetic bass sounds, like bass guitar, kick drum, keyboards, etc. A kick drum should produce a tight �thump� not a flabby , �boom. Bass melody or harmony lines should have notes that are � about equally loud. If some notes disappear, or stand out because they are consistently too loud, there is a problem. Disappearing notes have to be handled by moving the listening position, or the loudspeakers, to slightly different locations. Often, but not always, this will be enough. Excesses in bass tend to be most annoying, and energetic resonances that cause �boomy� or �lumpy� bass can be truly aggravating over a period of time. Infinity�s Bass Optimization System can fix this. So, the first step is to exercise your music collection, and listen for low-frequency problems that crop up in several different recordings. Something that only happens in one recording is likely to be a problem in the recording � it happens! If you identify something that is consistently wrong, select a record that shows it very clearly, and put your CD/DVD player into a repeat mode (A-B repeat is especially helpful, because you can isolate a short musical passage).
BASS OPTIMIZATION SYSTEM�
Infinity�s Bass Optimization System is a simple-to-use, yet sophisticated, low-frequency calibration system. Each Interlude IL50 or IL60 subwoofer contains a parametric equalizer that you can adjust by following the directions below. By following these instructions, you can improve the sound of your system.
The Bass Optimization System Goal
It is a fact of audio that what we hear at low frequencies is determined as much or more by the listening room than by the loudspeaker itself. Placement of the loudspeakers and listeners and the acoustical characteristics of the room surfaces are all important determinants of bass quantity and quality. In most practical situations, there is little that can be done about this,
INTERLUDE
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