Racket stiffness not the whole story?
Today I took my APD gt and my new head youteck speed pro (18 mm beam) out for a hit. I matched them completely. Same weighting, strings, and grip. I was surprised to find that while they have the same stiffness (70 RA), the speed pro hit quite a bit softer in comparison. It had almost a mushy feel to hit and the ball came off with a bit less spin and pace. Could this have something to do with the difference in beam width or shape despite the frames having the same stiffness?