Mostly from a stop until 45-50 mph. It'* heard and felt mostly from the passenger front foot well where the floor angles up at the side of the car.
It'* been getting worse and I haven't really figured it out yet.
So far I've put a new front motor/trans mount in, the previous owner put a new dog-bone motor mount in on the lower rr of the engine.
I've had it up on a hoist 4 times and can see nothing that is grinding.
This is on my 95 SLE, and it also is doing the same thing in my brother'* sister-in-laws 96 SLE.
I see no tears or scraping on the cv joints. I don't see anything.
It'* so bad on my car I wouldn't doubt the knock sensor is picking it up and pulling timing as it seems the car has alot more lag at the low end since its gotten louder/heavier in the past 2 weeks. Heck, I can hardly get a tire chirp now whereas before with nice cold air I could leave twin strips for 20-30 ft.

Just some ideas:

Brakes dragging
Wheel bearing
Differential
Harmonic balancer
PS pump
A/C compressor
Water pump

How bout a CV joint. They don't have to tear a boot to go bad