We have some supermicros that have about 12TB RAM, but the built in fans sound like a jumbo jet taking off so consider the noise pollution for a second there.
Er, are you summing a TwinBlade chassis? You have to be.
6TB is about where single machines currently top out due to the hardware constraints of multiple vendors and architecture, and memory bandwidth starts being an issue. You have to throw 96x64GB at the ones that exist so wave buh bye to a cool half a million USD or so. If you're sitting on a 12TB box I want a SKU (I want one!).
I don't actually think Supermicro makes a 6TB SKU, even. That's Dell and HP land.
We do have a twinblade chassis, but I'm pretty sure they are a 6TB SKU. To be honest, I'm not the one who procured them so I can ask if you are interested in a SKU.