Trying to find the source of a noise on a bicycle can be an exasperating experience. As a previous poster said, the dang noises can be amplified through out the frame. I certainly would try the "go back to the old pedals and see what happens thing." If its still there it could be the bottom bracket. But you can't rule out such things as a hub that needs adjusting, a loose head set, even loose handle bars. All of these areas are can be stressed in synch with pedal rotation. depending on your pedaling style. And remember when the noise is at left pedal top dead center, right pedal is bottom center so it could also be there. I could have sworn my latest clicking was from the bottom bracket area, but it was the rear hub. Five minutes to adjust and noise gone. I once had a clicking that drove me nuts. I could not find anything wrong with the bike or my cleats. Then I decided to take the cleats off (they came on the shoes) and ther under the cleat was another fastener for another type of pedal which could slide in an adjsting channel. The fastener would slide to the end of its allowable travel point on every pedal revolution and hit the end with a click. I wish you good luck on your quest for quiet.