Vibrational noise vearing left and going over depressions

What is your question?

When the car is up to speed (45mph or more) and I am not accelerating but the engine is under a load, not in neutral (it is a stick shift) is when I notice the noise most. I almost sounds like I am going over rumble strips although not as much vibration. As I turn to the left (not right interestingly enough) on a curve or when I go over an uneven surface there is a vibrational noise. What should I look at to diagnose where the noise is coming from?

What makes this problem better or worse?

curving left makes it worse