Gearboxing Mode - Antelope ISOCHRONE TRINITY User Manual

37. SD Video Outputs
BNC connections which provide SD video outputs as follows:
● SD 1 NTSC with black burst.
● SD2 PAL with black burst.
● SD3 NTSC 30 or PAL 24 composite sync. Toggled via front panel button (17).
● SD4 PAL 47.95 or PAL 48 composite sync. Toggled via front panel button (17).

GEARBOXING MODE

In Gearboxing Mode, Trinity always generates an output clock at the sample rate set by the
SAMPLE RATE knob for each channel, regardless of the incoming reference frequency.
This output clock is still phase-locked to the reference input, but the sample rates need
not match.
For example, you may set the SAMPLE RATE for AUDIO Channel A at 48kHz and apply a
44.1kHz reference. The device then 'gearboxes' 44.1kHz into 48kHz output as chosen by
the SAMPLE RATE knob for that channel. The ability to lock to one sample rate and
generate another is very useful for sample rate conversions. Gearboxing Mode dramatically
improves the sound quality of sample rate conversions.
For Gearboxing to work, the incoming reference must be one of 81 recognized valid
frequencies. A valid frequency is:
● One of the standard frequencies: 32, 44.1, 48, 88.2, 96, 176.4, 192, 352.8, 384kHz
● A standard frequency subjected to any of 8 possible combinations of US/European
pull-ups/pull-downs. Appendix A below contains a complete table with the valid
frequencies.
Note: Gearboxing can be disabled by using SPLIT mode. For this to work, at least
one of the AUDIO channels must be set to DA, otherwise the input is ignored.
SPLIT mode is to be used only if the input signal is known to be a varispeed
frequency and not a standard gearbox frequency.
Isochrone Trinity User Manual 17