Q: I have a 722. I also have a Canon XL2. Am wondering if purchasing the Horita PTG (SMPTE Time Code generator) could make the XL-2 be the source device and the 722 a sync device? PTG takes the composite video signal from my camera, and derives the time code for it. I am not sure if "word clock" is compatible with SMPTE time code? If the above setup won't work, can the XL2 be made to lock sync with the 722? Both of them are set to 48 kHz, but - XL2 is only 16-bits, while 722 is set to 24 bits. What hardware generates a 722 compatible "word clock" from a composite video signal - if Horita PTG won't work with 722? A: Word clock and time code are related, but you will need a word clock signal for the 722 to accept it and lock its sampling rate to it. Our understanding of the XL-2 camera is that it does not have a genlock input nor a time code input. It uses its internal sync generator. That means that sound and picture will be running independently. For most applications, that is sufficient and marrying them in post will work well. However, for takes longer than ~15 minutes, there may be drift as each device will be clocked independently. Sample rate lock is not essential, but helpful. As long as each device holds its sync, you will be able to mate them in post. The tried and true method of using a slate (clap board) are still very relevant. I am not familiar with a device that generates word clock from a video signal. With such a device, you could clock the 722 from the composite output of the XL-2 camera.