> Isn't it inefficient to store the samples as 16bit? If storing the 10bit samples as a > bitstream you could store 8 samples in 10bytes instead of 16...
It's inefficient to store on your hard drive as such. For transmission from the Domesday Duplicator board to your PC, however, absolutely not. Consider that the FPGA would need to construct that bistream from incoming parallel data, for which there might not be enough free logic elements. All in all, keeping the dumper-side pre-processing as minimal as possible is arguably better.
It's questions like these where I wouldn't really blame Simon if he just packed it in and didn't want to deal with the MAME community. A bunch of people acting like the MAME team, the DU, and the Domesday Duplicator project are simultaneously smart enough to accomplish all these various things, yet too dumb to account for something as simple as that. It really gives a lousy impression.