Specifications

APPENDIX B
CAT. NO. 683 ELECTRONIC CROSSOVER
B.1 Description and Features
The Cat. No. 683 Electronic Crossover Board is designed for use in the CP500
Digital Cinema Processor. When installed in a CP500, it provides the following
features:
• Electronic crossover filters for three bi-amplified channels (L, C, R)
are configured to create a 4 pole Linkwitz-Reilly crossover, taking into
account common loudspeaker characteristics. The crossover frequencies
are programmable by means of 16 pin DIP headers containing resistors.
Standard factory values are presently 500 and 800 Hz, designed to
accommodate most popular cinema loudspeakers. Other frequencies can
be programmed by user-made headers.
• Low frequency driver time delays to ensure correct time alignment
of low frequency driver and HF horn signals. The time delay value is
programmable by means of 18 pin DIP headers containing resistors.
Standard factory values are presently 1.9 ms and 0.8 ms, designed to
accommodate most popular cinema loudspeakers. Other delays can be
programmed by user-made headers.
• Low-pass filters for use with two (Ls, Rs) surround bass bins. Two
pole filters are provided, programmable with a 16 pin DIP header. As
delivered, this is the same header furnished on the Cat. No. 682 and is
reversible to accommodate either 50 or 100 Hz Butterworth filter
characteristics. These filters plus the high-pass filters on the Cat. No. 682
provide the ability to bi-amp the surround channels in order to improve
the bass response and the power handling capabilities of these channels.
• A secondary crossover system with manual adjustments for use
when in Bypass.
• All adjustments necessary to permit correct alignment and
equalization of a complete bi-amplified system.
B.2 Installation
Remove Cat. No. 682 from the CP500 and move jumpers J901, J3, J4, J5 to the
"YES" position to enable the crossover features of the Cat. No. 683.
The Cat. No. 683 is installed in the left-most slot (J1) in the CP500 after jumpers
and headers are configured. When the Cat. No. 683 is installed in a CP500, the
MAIN screen channel connector on the rear panel becomes the LF output
connector. The HF horn outputs are available at the additional rear panel connector,
XOVER OUT, located to the right of the main output connector. The Left and
Right Surround bass speaker outputs are also available at this connector. An ID pin
on the card automatically tells the Cat. No. 684 System Controller card that a
crossover card is present.