A little late to the party here. The SA12/e is a parallel amp design and the S1600e is bridged design. You would need to add a second FEB to the 12/e to convert to the 1600e. Both the SA12/e and the S1600e have 2 amps inside each monoblock. Parallel set up in the 12/e and bridged in the 1600e. Thus you need a second FEB for the inverted bridged connection to the second amp in the 12e to make it a 1600e. But, if you have a 1600e, you should be able to convert it to a 12/e with whats in there. I got this from the service manual of the 12/e which I have posted on DIYAudio. I have not read enough into it to know how you'd set bias, but I'm sure that could be figured out.
Disclaimer .... I may not really know what I'm talking about. If you have a 12/e or 1600e, better run this by Mr. Pass before you dive in with wire cutters and soldering iron!
Disclaimer .... I may not really know what I'm talking about. If you have a 12/e or 1600e, better run this by Mr. Pass before you dive in with wire cutters and soldering iron!