Pull Up/Down (Vso); Wc Out 5 - Apogee BIG BEN User Manual

BIG BEN – User's Guide
Navigating the Front Panel -
In VSO mode:
due to the limitations of a
4 digit display, only one
of the three units of measurement
can be displayed accurately; display
values for the remaining two units
are approximated. Whichever unit
of measurement is displayed when
modifying SAMPLE RATE accurately
represents the output; if a second unit of
measurement is selected and SAMPLE
RATE is modified, that second unit of
measurement becomes the accurately
displayed unit. For this reason it's
recommended to choose the unit of
measurement desired before setting the
SAMPLE RATE value.
When in VSO mode, please
note that the SAMPLE RATE
value is not retained in Non-
Volatile memory, and will be lost when
Big Ben is power cycled. All other
settings are memorized.
To clock most digital systems, a word
clock of the same frequency as the
audio sample rate is required. For
those systems where the required word clock
is a multiple of the sample rate, WC Out 5 & 6
may be set accordingly.
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8) PULL UP/DOWN – The Pull Up/Down parameter is active only
when SAMPLE RATE is set to INTernal or VIDEO. The frequency of
the SAMPLE RATE may be modified by 4 defined percentages to ac-
commodate specific situations encountered during video production
and post. The +- 4% values are usually employed when transferring
between PAL video and film, while the +- 0.1 values are employed
when transferring between NTSC video and film.
VSO (Variable Speed Override) is the term historically used to
denote the variable speed control on a tape machine. Variable Speed
is accomplished in the digital audio domain by modifying the sample
rate. Big Ben allows this modification of the SAMPLE RATE over
a wide range of values when CLOCK SOURCE is set to INTernal
and the PULL UP/DOWN parameter is set to VSO, Moreover, the
SAMPLE RATE may be displayed in three units of measurement : 1)
absolute frequency in Hz 2) amount of change in percentage, and 3)
amount of change in cents (i.e. subdivisions of a semitone).
For VSO operation,
1) Ensure that CLOCK SOURCE is set to INTernal, and that the
desired base SAMPLE RATE has been selected.
2) Set PULL UP/DOWN to VSO
3) Select the SAMPLE RATE parameter, and set the desired
amount of varispeed with the UP or DOWN buttons (Pressing
and holding the UP or DOWN key causes values to scroll more
rapidly) The SAMPLE RATE value will now vary in increments of
1 hz,, 0.1% (1% when the amount of change is greater than 10
%) or 1 cent, depending on the unit of measurement displayed.
To change the units of measurement displayed, select the SAMPLE
RATE parameter and press and hold either the PREV or NEXT button.
To reset the SAMPLE RATE to an unchanged state, select the SAM-
PLE RATE parameter and press and hold both the UP and DOWN
buttons. Alternatively, it's possible to toggle the PULL UP/DOWN
parameter between NONE and VSO.
9) WC OUT 5 – This parameter allows the frequency of Word Clock
Output 5 to be set to a multiple of the SAMPLE RATE.