John's suggestion would be a good thing to try but I don't think the woofers will give that mid warmth. BTW, I now have my M80s running bi-wired on A+B. I wanted to hear what the woofers and mids/tweeters sounded like separately. The woofers on their own almost sound like Bose 501s (a slight exaggeration but not too far off) and the mids/tweeters like M22s. If I disconnect one of the mids and tweeters, I wonder if they'd sound like M60s?

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated