And, I guessed right, for once!
But, much as I like my new Buckeye Amp, ain't nobody getting my SDP-75...
I have a vague memory that it was an older Denon that a guy fried the trigger circuit with a 100+ mA relay; Denon said it was rated for 50 mA. Don't quote me, I may be wrong. And at the time I was explaining why snubber diodes and a bit of RC was critical across relay coils and contacts to prevent large voltage spikes, so I am not sure what exactly blew out his AVR's trigger circuit. The Emotiva repeater was cheap insurance for many $$$ worth of components.
I built a trigger circuit using a small relay to switch a 12 V wall-wart through a small resistor to limit current
if when I accidentally short the output. I can source about 750 mA. More than enough margin. I suppose that means I need more amplifiers...