Turntable and cartridge setup known for a marvelous bottom end.

well, you want to avoid a bloated low end. are you chasing something that isn’t there, and shouldn’t be?

best arm/plinth/spinner in the world should not be adding a bottom end, or anything for that matter, purpose is to prevent all problems, and to properly transmit fidelity.

CARTRIDGE

I’ve never heard one, but the Hana SH cartridge specs are certainly excellent, and if the low content is there, it should be sending it ...

Is it broken in, stylus/cantilever/suspension not worn/dried out, do you have the skills, tools, and are you confidenct that it is properly aligned in every way? Tightly fastened to Arm? Headshell rigid and rigidly fastened?

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Is it possible the cartridge is defective?

Perhaps change only the cartridge first!

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Have you asked Project for their advice about this?

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After that, if still in search of, I would try to determine suspected weak link

Then Arm, everything tight? are the vibrations getting down the line?

Arm to Plinth solid

Plinth not absorbing lows?

Phono cable (caution, my expensive one made zero difference) better ’protection’ from interference that doesn’t exist gets you nothing except less $.

I like the Technics 1200G and the Pickering XSV 3000.  Nice analog sound with very good bottom end.

I am not sure you have asked a "good" question, but my Stanton 981LZS has particularly excellent bass clarity and downward extension.  Really, low bass in the room will depend upon many many other factors, besides the cartridge and TT, not the least of which is the tonearm.

+1 @lewm 

i too was hesitant about a sub. My speakers are supposedly down to 20hz. It wasn't until I added a sub that I got the bass I was looking for. My point is, just because the specs say so doesn't mean it produces it at a level that you like. You will need to do more than change TT's & cartridges. Bite the bullet and get a  Rel sub which integrates very good and enhances your speakers output as well. Just my opinion