Weseixas - While the 40.1's would not appear to be easy to drive by looking at the efficiency rating (spec'ed @ 86db/1w/1m), they have a flat impedance curve, rated at 6 ohm nominal / 5 ohm minimum. Furthermore, the beauty of the Harbeth sound is that you don't need to crank up the volume to ear splitting levels (like I had to do with my Dynaudio C4's) to get them to sound their best.
Also, even though some at Stereophile had some critical things to say about the Harbeth 40.1's, they still gave it a class A rating.... also TAS gave it their Golden Ear award, so I think there's strong consensus that it's a highly acclaimed speaker, albeit not for everyone.
Also, even though some at Stereophile had some critical things to say about the Harbeth 40.1's, they still gave it a class A rating.... also TAS gave it their Golden Ear award, so I think there's strong consensus that it's a highly acclaimed speaker, albeit not for everyone.