You could use them as "real" Neve 1272 like buss/summing amps.
The GA73 does have a line input but the Neve 1272 was basically the output circuit of the 1073 with a Mic input transformer as the buss/summing input.
If you go into the mic input transformer and turn the gain all the way down then you basically would have a Neve summing amp.
Cheers, Dave
Would it be difficult to match the levels - and does it take line input...?
cheers

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