Strange rumbling/vibration when I drive my car over 40 miles an hour. What's wrong with it?

So over the last week whenever I drive my car over 40 miles an hour I hear this sort of rumbling noise and feel a vibration underneath my feet. It seems to be getting worse every day. It almost sounds like a machine gun or something. Any idea what could be wrong with my car?
Added (1). This car is a 97 Honda Accord. Mileage is 109,000. I usually keep up to date with any issues that arise, it's a good car but old and there's always something wrong with it lol. I just got 4 new tires recently I was thinking that the noise came from that, that's when everything pretty much started, it's just gotten worse over the last few weeks. I also need to get my car realigned, could that be the cause?

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