L-ACOUSTICS LA4X [36/47] La4x amplified controller

LA4X AMPLIFIED CONTROLLER

USER MANUAL

VERSION 2.0

LA4X_UM_EN_2.0 w w w . l - a c o u s t i c s . c o m 36

When the LOCK status has been recovered, the user can manually reactivate channel pair AB applying the sequence

described in Figure 35:

Figure 35: Reactivating channel pair AB

4.9.2 FALLBACK MODE

An automatic fallback option can be enabled or disabled. When enabled, and when the AES/EBU input mode is

selected for input pair AB, the amplified controller will automatically switch from input pair AB to input pair CD in case

of digital signal failure on input pair AB (no clock, loss of lock, CRC error, bipolar encoding error, data slip). This option

prevents sound cut.

After the digital signal has returned to normal state, reverting to input pair AB is not automatic and must be done

manually by the user. This can be done simultaneously for all concerned amplified controllers from LA NETWORK

MANAGER software.

Precautions for using the automatic fallback option

Before enabling the automatic fallback option, some precautions have to be taken in order to avoid sound cut or

level differences in case of switch from input pair AB to input pair CD:

 Input pair CD must be connected to an audio source (analog or digital) playing the same program as the digital

audio source connected to input pair AB.

 When an analog audio source is connected to input pair CD, the level of the digital audio source connected to

input pair AB must be aligned to the level of the analog audio source using the AES/EBU GAIN control (see

section 4.9.3).

Two FALLBACK MODE settings are available, as described in the following table:

Table 8: FALLBACK MODE settings

OFF

Automatic fallback option disabled.

The sound will be cut off in case of digital signal failure on input pair AB, but it will

automatically be recovered when the signal has returned to normal state.

Automatic fallback option enabled.

Input pair CD will automatically be selected in case of digital signal failure on input pair AB.

Revert to input pair AB is not automatic and must be done manually by the user.

To select the fallback mode follow these steps (see also Figure 36):

From the main menu select INPUT SETTINGS and press the OK key or the encoder wheel (or ESC to 1.

abort).

Turn the encoder wheel to select FALLBACK MODE. 2.

Press the OK key or the encoder wheel to enter the page (or ESC to abort). 3.

Turn the encoder wheel to select the chosen setting. 4.

Press the OK key or the encoder wheel to validate the setting (or ESC to abort). 5.

Figure 36: Selecting the fallback mode

Invalid audio (validity bit)

A validity bit at non-audio value will not trigger the automatic fallback. Instead the signal will be muted.