4 or 8 ohm with Harbeth

try both and listen to which one you like best.

I've tried both the 4-6 and 6-8 taps on my amp and like the 4-6 better. Try them and see.

I own an ARC VS-115 which has 4 and 8 ohm taps. Although my fronts are nomonally rated at 8 ohms, the impedance drops to 4+ ohms in low bass. A couple of A'gon technies suggested that I try both taps and use the taps that sound better. I did. Interestingly, while the specs "suggested" that I might do better with the 4 ohm taps, the fonts sounded like they were being driven under water. I switched to the 8 ohm taps and all is good.

So, I agree with Riley and Tom. Tried both and use the taps that sound better. Good luck.

Ditto above,try both and decide for yourself. After all, you are the one that that's listening. If you're worried about damaging your speakers, don't.