Mcintosh 7270, impedance with Martin Logan Request.

I wouldn’t be surprised if your ML’s dipped down to 2 ohms at spots- I would probably go with the 2 ohm, but I’d also listen at 4 ohm and see which I preferred.

Recall, the 4 ohm rating is ’nominal’ and really doesn’t tell you anything of the impedance spread over the audio band.

i agree with zavato. try both.

Actually, try all three; 8, 4, and 2. The main difference is the output impedance/damping factor and the results will depend on your set up. I have found my Aerious i sounds best using the 8 ohm tap on my MC2200. The 4 ohm tap was very close but rendered a narrower soundstage. 

Thanks everyone for suggestions.