4 Low Frequency Fine Tuning

The Symbol Subwoofer will produce prodigious quantities of low frequency energy with accurate phase and transient response. Any thickness or overhang in the low frequency presentation will be easily discernable and is the direct result of improper setup. The following guidelines should be regarded as a sound starting point; those who have extensive experience in sophisticated low frequency tuning may improvise beyond these rules of thumb.

Placement

For best phase alignment the Center/Subwoofer combination should be at the same plane as the Symbol Satellites. Since this is the case, the Subwoofer will optimally be placed a few feet from the wall on which the video will be displayed, centered from left to right between the Symbol Satellites. Any deviation from this configuration should be re-aligned through compensation within your surround sound processor. Most processors will have easily adjustable “distance to listener” parameters. Once a final position has been determined, the included spikes should be installed, leveled and locked in place with the supplied spike nut.

Any low frequency acoustic transducer will produce non-uniform loading when in close proximity to a boundary layer, such as a wall. Full output at low frequencies and accurate transient response will exacerbate this effect. For this reason it is strongly recommended that a DAAD4 acoustic device (more information is available at www.acusticaapplicata.com ), be placed between the Subwoofer and wall horizontally on the floor. Absorption of this energy buildup will reveal much of the true transient characteristics of the system.

Surround Sound Processor Tuning

Most sophisticated SSP chipsets allow flexible bass management. Usually flexible crossover points between sub and satellites are matched with second order filter slopes. In such cases the crossover point should be set at approximately 60 Hz (+/- 5 Hz), with both the Subwoofer and Symbol satellites being actively crossed. The Symbol Subwoofer should ALWAYS be set to the HIFI MODE under these circumstances. Overall satellite to Subwoofer volume balance should then be adjusted for optimal results. Usually the appropriate Subwoofer gain setting will fall between 65 and 70 on the digital display. Matching the “speed” between satellites and Subwoofer is critical. Miniscule changes in Subwoofer gain will result in significant differences in overall presentation, and should be fine tuned through SSP subwoofer gain settings.

Only when any thickness or overhang has been eliminated in the 60 Hz-120 Hz region by careful gain adjustment, will the system perform as designed.

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