User`s guide

APOGEE ELECTRONICS

AD-16X – User’s Guide

Saving calibration

settings

7) CAL mode indicator – This LED indicates that either Global or Channel CALibration mode is enabled, and that the

analog to digital conversion level may be calibrated. Global CAL allows the calibration of all 16 channels simultane-

ously, while Channel CAL allows calibration of individual channels. Global CAL mode is enabled by scrolling through

the 7 front panel parameters until the CAL LED ﬂashes; “global Cal” will scroll across the Sample Rate display,

followed by the digital output level of channel 1. Once enabled, all 16 analog input levels may be adjusted simultain-

eously by one of three operations:

• Press and Hold UP to raise the analog input level and DOWN to lower the level.

• Press and release UP or DOWN to modify the analog inputs +-.01 dB;

• Quickly tap UP or DOWN twice (think of a double mouse click) to modify the analog inputs +- 1.0 dB.

This double press function may be used to quickly jump from a “house” reference level to another

reference level in precise 1 dB steps.

Channel CAL mode is enabled by scrolling through the 7 front panel parameters until the CAL LED ﬂashes,

then pressing and holding either the PREV or NEXT buttons until “ch 1” scrolls across the Sample Rate display.

Keeping in mind that Setup mode is always enabled while in Channel CAL mode, channel 1’s analog output may

be modiﬁed by the same operations described on the previous page. To adjust channels 2-16, press either the

PREV or NEXT button until the LED corresponding to the channel to be modiﬁed is lit.

To exit Channel CAL mode, press and hold either PREV or NEXT again. Keep in mind that values entered while

in either Global or Channel calibration mode won’t be saved in non-volatile memory until Channel CAL mode is

exited and the Setup mode LED goes out.

When either Global or Channel CAL modes are enabled, the Sample Rate Display operates as a digital level me-

ter with a range of -24 to 0 dBFs; if the level is below -24dBFs (or there is no analog input present), the Display

will read “----”. In Global CAL mode the level of Channel 1 is indicated; when in Channel CAL mode the level of

the selected channel is indicated.

Individual channel level changes made in Channel Cal mode are preserved when modifying all channel levels in Global Cal mode.

To quickly calibrate the AD-16X, reset the unit (by pressing DOWN while powering on) and connect a 1 kHz tone

at the desired analog reference level (usually +4 dBu) to channel 1. Enable Global CAL and press UP or DOWN

to modify the level indicated by the Sample Rate Display to the desired digital reference (usually between -20

to -12 dBFs). Keep in mind that digital levels are expressed as a minus reading below 0 dBFs; thus a change from -16

dBFs to -14 dBFs is an increase of the coversion level.This procedure calibrates ALL channels to approximately the

same conversion level.

To reﬁne the calibration of each channel, press and hold either PREV or NEXT to enter Channel CAL mode,

connect a 1kHz tone to the channel to be modiﬁed, select that channel using PREV or NEXT (the selection is

indicated by the red ﬂashing LED) and press UP or DOWN to attain the desired digital level.

8) UV22HR – This LED indicates the status of UV22HR processing, which reduces bit resolution from 24 to 16

bits when applied to the converted digital signal . When the UV22HR LED is illuminated, UV22HR process-

ing is engaged on channel pairs selected in UV22HR Channel Select Mode. To enable this mode, press

and hold either PREV or NEXT (while the UV22HR LED is ﬂashing). To select channel pairs, press PREV

or NEXT until the red OVER LEDs of the desired pair are lit, and press UP or DOWN to select the pair, as

indicated by the illumination of the corresponding green LEDs. UV22HR may only be engaged when the

SAMPLE RATE is set to 44.1 or 48kHz

Navigating the Front Panel - continued