I replaced my output caps with the Jantzen Superior z-caps on my Jasmine. I don't recall any brightness. Rather, it was like lifting a veil that resulted in greater clarity and life. I use a Denon DL-S1.
Have you checked the VTA on your tonearm? I use a magnifying glass and observe the angle of the stylus in the record groove and strive for 90 degrees. Then, I move the arm up or down for the best sound. I also lean towards the highest tracking force so the stylus properly tracks the grooves instead of skimming past the tiny undulations. When I lose dynamics, I know it is too heavy.
Have you checked the VTA on your tonearm? I use a magnifying glass and observe the angle of the stylus in the record groove and strive for 90 degrees. Then, I move the arm up or down for the best sound. I also lean towards the highest tracking force so the stylus properly tracks the grooves instead of skimming past the tiny undulations. When I lose dynamics, I know it is too heavy.