Usl XTM-300, Инструкция по эксплуатации

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Screen and Horn EQs:
Generally, all six dipswitches should be “On”.
In some cinemas, the left and right speakers are mounted outside the screen area. In this case,
turn the left and right screen EQ switches to “Off”.
Some high frequency horns are very flat to 20kHz. In this case, you may want to turn the horn
EQ switches to “Off”.
The screen and horn equalizers each add a shelving high pass filter boosting 7kHz by 5dB and
20kHz by 8dB. The combination of horn and screen EQ results in about 16dB boost at 20kHz.
Using a Real Time Analyzer and feeding a pink noise signal from the cinema processor, set the
appropriate trimpots for a flat response around the crossover frequency and a total SPL level of
85dB on each of the front three channels. There should be enough range in the output pots to
allow setting the amplifier gains between 50 to 100% of maximum.
Set the NORMAL/BYPASS switch to BYPASS.
The Bypass Crossover is fixed at about 430Hz with no time delay. It combines the left, center
and right signals and then feeds the center output only.
Using a Real Time Analyzer and feeding pink noise from the center channel of the cinema pro-
cessor, set the bypass levels for flat response around 400 to 500Hz and SPL level of 85dB.
Return the BYPASS/NORMAL switch to NORMAL.
9. XTD-680 Setup
Digital Crossover Module Instructions
The USL XTD-680 is a digital crossover card for use in the XTM-300. When used in the XTM-
300, the XTD-680 provides bi-amp crossovers for the left, center, and right channels. It also
provides gain and delay controls for the LFE channel. The card is configured using a graphical
user interface running on a laptop computer. The computer communicates with the XTD-680
over USB. A library of standard cinema speakers is provided. In addition, specific crossover
characteristics can be set manually. The XTD-680 also includes a passive bypass crossover
for emergency use.