Actually, there is no Model 6B, only the Model 6 (shown above). I haven't heard any Aerial speakers, so I can't comment from personal experience. Stereophile's review of the 7B includes its specs, which I compared with those of the Model 6 from Aerial's website. They are almost identicalvirtually the same bottom end (35Hz for the 7B versus 38Hz for the 6), the same sensitivity (86dB/W/m), and the same nominal impedance (6Ω).
In terms of drivers, the 6 and 7B are very similar as well. Both use the same tweeter, midrange, and woofer, though the 7B has two woofers while the 6 has one. According to Aerial, they are voiced similarly, so they should sound very much alike.
All that being said, the 6 is actually better-suited for smaller rooms because it's front-ported, while the 7B's port is on the back. This allows the 6 to be placed closer to a wall, which could be important in a smaller space. Given that you like the sound of the 7B, I recommend that you get the 6 for your new, smaller digs.
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