While there's really no reason not to make the 212 equal to 2 x 112, in this case I think there's an opportunity to push into new territory a bit with the 212 version.
Part of what happened is, a very useful little part recently became available that I think will make it practical for me to combine the Hathor's open-format midchamber with a good little horn-loaded compression driver. I'm not a big fan of the more compact bullet tweeters because they inherently beam pretty badly... a 45 degree pattern width (-6 dB at about 22.5 degrees to either side) is pretty much the norm for a bullet tweeter, but the baby butt cheeks horn w/compression driver that I use has a roughly 90 by 90 degree pattern, which is imo a worthwhile improvement.
My understanding is that the Hathor 1203 is okay but not great on upright. I'm working on a small cab for upright bass... or will be again hopefully next week. I lost several days to a bout of stomach flu, still not back up to speed yet, but will get back to work soon as I post this. There's two empty Hathor 1855 enclosures stacked in the living room that are calling my name...
I'm aware of quite a few posts that still call for a response from me, and I'll get to them when my brain is a bit less foggy, hopefully tomorrow.
Duke, the TC series is INSANE for upright. I never realized how much I had to fight my cab to find a good upright tone until I got the TC. That is why I will always keep a TC 112 around. I personally don't feel the need for smaller cab, but I know some upright guys might. It is small enough and light enough to do the job for me.

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