I have a very noisy front end at above 20 mph.

It could be that you have a front wheel bearing that is getting noisy. Have someone ride in the RF seat and listen to the noise to try to figure out which front wheel the noise is coming from.
Also , check the tread pattern of the front tires to see if it has some unusual choppy pattern forming.

If it is the tires, the noise will change on different road surfaces. If it doesn't, then you have a bad bearing.

prob wheelbearing or hub they roar

I have a 98 Ponitac Grand Prix GT. Soon as you start going it starts roaring. Gets loader the faster you go till 70 mph. When I am turning to the right a little while going 60 mph the sounds quiets down. Only to the right. I have replaced both wheel bearings, got brand new tires, new brakes. Didnt stop the roaring. Would it be cv axles, rack & pinion, transmission, etc?

You mean 50 MPH? could be tires noisy or a rear wheel bearing.

it can be any of the above, rotate the tires and see if the noise location seems to change, but the last thing i would suspect is the CV, they just click when turning, the wheel bearing is my choice here, they roar, tires make a diff noise.

I just had the same issue with a 1999 2500HD and the vibration got worse above 50 mph. Problem was resolved with a new driveshaft. Old one (aluminum) was badly out of true and the problem didn't really occur until I had the U joints changed - then bent driveshaft vibration was noticeable. New driveshaft resolved issue.

I certainly would take it back to the shop that performed the brake job and have them investigate. If it was not making the noise prior to the repair there is a good chance the noise is involved with the brakes. A possible loose brake pad, a sticking caliper(caliper pins may need to be lubed) or any number of things could be wrong.

THIS NOISE IS USUALLY THE HUB. HAVE SOMEONE GO WITH YOU ON A TEST DRIVE. GET THE ROARING TO HAPPEN AT ITS LOUDEST AND GENTLY SWERVE THE CAR LEFT AND RIGHT. DON'T BE SURPRISED IF YOU THINK BOTH HUBS ARE BAD. LIFT THE FRONT OF THE CAR AND PUT IT ON JACK STANDS. PULL OUTWARD ON THE BOTTOM OF THE TIRE WHILE PUSHING INWARD ON THE TOP OF THE WHEEL. IF THE WHEEL MOVES EXCESSIVELY YOU FOUND THE HUB THAT IS NOISY. USING A MECHANICS STETHOSCOPE YOU CAN SOMETIMES HEAR A ROARING TYPE NOISE ON THE BACKING PLATE SIDE OF THE HUB WITH THE ENGINE RUNNING AND THE TRANS IN GEAR. TRY NOT TO GET THE SPEED UP TOO FAR ESPECIALLY IF YOU CAN HEAR THE NOISE AT LOW SPEED, YOU DON'T WANT TO VIBRATE OFF THE STANDS.

I have the same thing. It started last summer when I had about 20,000 miles. I just took it into the dealer. They say it is the antenna and that they removed it and tested drove it and the noise went away. Mine starts around 35 mph. I don't know if they are pulling my leg and there is a bigger problem that the financially strapped GM won't fix. I also have a bad CV joint and unless it goes out within the next 500 miles, GM won't replace it.