Avid Technology FC726, Manual

FC726 Guide

8

6. DIP Switches

These eight DIP switches (numbered 1–8 from left to right) set 
various modes on the FC726. Switches 3–5 and 7 are not cur-
rently implemented.

Switch #1 Bidirectional mode

Flip this switch when converting between third-party formats 
using one FC726.

Switch #2 MADI MERGE

When set to MADI MERGE (down), Format B MADI Input 1 
channels 1–24 are merged with Format B MADI Input 2 chan-
nels 1–28 and Format B MADI Input 1 channels 25–28 to form 
a single 56-channel input stream. Format B MADI Output 1 
sends channels 1–56 and Format B MADI Output 2 sends 
channels 25–56 followed by 1–24 from the third-party inputs.

Switch #6 AES MASTER/SLAVE

When set to SLAVE (up), the Format A AES outputs lock to 
their corresponding AES inputs. Within each bank, all AES 
outputs operate at the sample rate of the lowest-numbered, 
locked AES input. For example, if the first bank (channels 1–8) 
has a 44.1 kHz AES signal connected to inputs 1–2 and a 48 
kHz input connected to inputs 5–6, then AES output channels 
1–8 will all run at 44.1 kHz. If AES inputs are not present on a 
bank, Format A will get sample clock from the Format B Sync 
input. If sync is not present, Format A will then lock to the 
Format B Sync Input.

When set to MASTER (down), Format A AES outputs get sam-
ple clock from the Format A Sync input. If Format A sync is 
not present, the Format A AES outputs will then lock to the 
Format B Sync Input.

Switch #8 AES STEREO/AES MONO

Set this switch to AES Stereo (up) for the normal configuration 
where each AES signal contains two discreet channels. If the 
sample rate is above 52 kHz (such as 88.2 or 96 kHz), and the 
AES signal connected to the FC726 implements two-wire AES 
(also referred to as mono mode AES), set the switch to AES 
Mono (down). This setting treats each AES signal as a single 
channel with a frame rate running at half its sample rate. For 
example, a 96 kHz two-wire AES signal runs at 48 kHz by using 
the left channel for the even samples and the right channel for 
the odd samples. This switch affects both the AES inputs and 
outputs.

7. Format A AES Sync In

Connect an AES sync signal to this XLR connector to synchro-
nize the Format A MADI signal. According to the AES specifi-
cation, the AES sync signal must use the same sample rate as 
the incoming MADI signal to operate correctly. 

8. SDIF-2 or SLAVE CLK IN

This connector can receive either an SDIF or slave clock sync 
signal. The FC726 automatically detects which signal type has 
been connected. 

An SDIF device must send a word sync signal to this connector 
to properly connect to the FC726. 

9. SLAVE CLK OUT

If Slave Clk In has a valid sync signal, it is passed through to 
Slave Clk Out. If Slave Clk In does not have a valid sync signal, 
the lowest numbered bank that is locked and in use is selected 
as the clock source. 

It is possible, but not recommended, to connect a 
MADI signal without using a corresponding sync 
signal. Providing an AES or Word sync results in 
lower jitter and should be used whenever possible.