Directed Audio 1200T manual Subsonic Filter Adjustment, Sealed Enclosure, Ported Enclosure

SUBSONIC FILTER ADJUSTMENT

This amplifier incorporates a subsonic filter to maximize the performance of a subwoofer. The subsonic filter is a high pass filter that removes unwanted bass output at very low frequencies from the woofer. This increases the output of a subwoofer by as much as 3 dB by increasing the mechan- ical power handling of the subwoofer. Depending on the type of enclosure the subsonic filter can increase the useable low frequency output by an additional 10 dB! Acceptable boost levels are determined by the type of enclosure used, wattage of the

amplifier, and the woofer’s excursion capa- bility.

To adjust this filter, place the Subsonic Filter switch to the IN position and turn the Subsonic Frequency adjustment to the desired frequency (15–50 Hz).

The following guidelines should be used for proper set-up of the subsonic filter to provide optimum performance and relia- bility from your system.

„	Sealed Enclosure:	Set to Fs of the woofer or higher.
„	Ported Enclosure:	Set to tuning frequency of enclosure or higher.
„	Sealed Bandpass:	Set to Fs of enclosure.
„	Ported Bandpass:	Set to low tuning frequency of enclosure.
„	Infinite Baffle:	Set to Fs of the woofer or higher.
„	Aperiodic:	Set to Fs of the woofer or higher.

© 2004 Directed Electronics, Inc 15