Door or seals in a rental property

I literally did this swap last month. Started cheap: adhesive perimeter gasketing and an automatic drop seal under the door—big leap for speech leaking from the corridor. Later I replaced the hollow-core with a solid-core slab and that tightened the low/mid frequencies even more, but only after I tuned the latch side and threshold so there were no gaps. Also check the frame: tighten hinge screws into the stud and add a sweep or threshold if needed. If you want a quick sanity check, I got a friendly walkthrough from New York Soundproofing—they explained why mass + airtightness beats either alone and helped me phrase a simple ask for my landlord. If approval’s tricky, try seals first; if you can change the leaf, do both for the best result.