Notes
DIGITAL PERFORMANCE WITH OVERSHOOT PROTECTION YIELDS MAXIMUM LOUDNESS
The 8218 is an all-digital FM stereo encoder/generator with input flexibility, superb performance specifications, and a patented limiter that eliminates overshoots. Working with the OPTIMOD-FM 8200 or 2200 at the studio, the 8218 at the transmitter assures maximum loudness.
MAXIMUM LOUDNESS
OPTIMOD-FM processing produces a peak-controlled signal extremely well. Any change in the signal after the processing that adds overshoots will increase the peak-to-average ratio, forcing you to reduce modulation level to prevent over-modulation. This decreases the station's loudness. Analog studio-to-transmitter links add overshoot. Digital data-compressed links add overshoot. The filtering and pre-emphasis in most transmitter stereo encoders add significant overshoot. Combined, these overshoots force a reduction in loudness of 2 to 5dB. The Orban 8218 offers a complete system solution that maintains loudness. It includes a transparent digital limiter and overshoot compensator to eliminate overshoots introduced in the link. When used as a system with the 8200 or 2200, the 8218's encoder introduces no overshoot of its own, thus assuring maximum loudness and competitiveness, with no degradation of the clean sound produced by the OPTIMOD-FM processing.
INPUT FLEXIBILITY
The 8218 accepts left/right analog or AES/EBU digital inputs. The analog input can be flat or pre-emphasized. The digital input can be flat or pre-emphasized, and can also accept NICAM J.17 pre-emphasized audio, at any of the standard sample rates. The 8218 handles them all.
If digital input is selected, and the 8218 loses signal lock, it automatically reverts to the analog inputs until the digital input is restored, thus providing automatic switchover to a standby line. What's more, the 8218's digital input responds to status bits in the AES/EBU signal (from the 8200's SRC digital I/O card) to automatically sense and switch the 8218's pre-emphasis and/or J.17 de-emphasis networks.