Oh, I've got three chainsaws. I just figured "You go ahead first"...

Chainsaw juggler?

the midrange driver(s) are segregated, I believe with cylindrical tubes if memory serves.

About the M80's: According to an audioholics review:

"Let's talk ports for a moment. The M80ti(s) have three each, one on front and two on the back. The midrange drivers are completely isolated from the rest of the speakers via the internal chamber construction. The triple vortex ports are tuned solely for the dual 6.5" low frequency woofers, which contributes to them attaining such good frequency response."

And about the M60's:
The 5.25” woofer is actually encased in a sealed cylindrical enclosure. This ensures the proper box volume for the midrange to operate and isolation from the rest of the enclosure for optimal performance.

Now that I think about it, every >2-way speaker I've owned (well, both of them; a Fischer and a JBL) has been constructed this way with the isolated mid-range.

When I took them apart I didn't think anything extraordinary about the configuration. It just seemed the right thing to do. Are there manufacturers out there that expose the mid-range cone to the back-pressure of the woofer?

“cylindrical tubes”
Hmmm - that’s a little redundant

Actually, I would think a cylindrical tube would be a doughut.

Mmmmm, doughnuts.

You're making the bagels cry.

Cylindrical Tubes....a new Mike Oldfield album maybe?

OK, my tweeter went out over the weekend on one of my M60Ti. Removed the tweeter to confirm it was dead and did notice that the woofers are isolated from the mid and the tweeter. I also noticed the cylinder behind the mid. Very interesting. So yes, I've answered my own initial question that infact the woofers are separated from the mid and tweeter. No "chainsaw" needed this time around as the tweeter was very easy to remove.

Thank you all for responding.

jj