Sorry – I’ve been busy lately, so I haven’t been too active on the blog.
Here are some internal shots of the BeoLab 17 and BeoLab 20 loudspeakers. As you can see in the shot of the back of the BeoLab 17, the entire case is the enclosure is for the woofer. The tweeter has its own enclosure which seals it from the woofer cabinet.
What’s not obvious in the photos of the BeoLab 20 is that the midrange and woofer cabinets are separate sealed boxes. There is a bulkhead that separates the two enclosures cutting across the loudspeaker just below the midrange driver.