iternabe
The pivot on the VPC1 also is shorter than on the RHIII action of the ES920 or MP7SE. However, a seesaw action design like on the VPC1 is superior to a folded action design, so pivot length is not the only thing that matters.

      sweelinck However, a seesaw action design like on the VPC1 is superior to a folded action design, so pivot length is not the only thing that matters.

      This is something I have read a lot over in the other forum. Still I don't see a reason why this should be true. I mean, physics is physics and it is all about levers and weight and how the mass accelerates. If a seesaw design would be superior, the difference between Kawai wood actions and the Roland's would be night and day, but it isn't. I mean if mechanical principles would say so, the difference would be dramatic.

      Kawai wood actions are better than folded designs, but not because of the seesaw design - it is because of the materials used and because it is constructed more costly. And because the longer pivot point - at least longer than most folded actions.

          WieWaldi If a seesaw design would be superior, the difference between Kawai wood actions and the Roland's would be night and day, but it isn't.

          Well, there are many parameters that go into action quality, and there is a substantial subjective component, but for me that leads to finding Kawai's seesaw actions to be significantly superior to Roland's folded actions.

          A seesaw action has gravity from counterweighting of the other side of the balance rail to participate in resetting the key after release while a folded action must exclusively use springs.

              sweelinck a folded action must exclusively use springs.

              I don’t thinks the PHA-4 action in my Roland has any springs.

                15 days later

                iternabe
                Do you know the pivot lenght of the Fatar TP/400Wood action?

                    harri no, but if there is an accurate side profile picture I should be able to take a measurement.

                    • TC3 likes this.

                      @harri @TC3 Assuming the picture is proportionally accurate, here it is. Pivot length of FATAR TP/40WOOD would be 201 mm.

                      • TC3 likes this.

                      Is the Kawai RHCII any different than the RHC?

                      Enthusiastic but mediocre amateur.

                      The TP/400wood should be an upgrade of the TP/40wood but I have no idea what they have changed
                      I am looking for the technical specs but have not found any thing yet
                      Is there anybody who owns an DP with TP/400wood, and if so is there a description in the manual about the action?

                      hebele

                      I remember reading that pivot length in acoustic pianos also varies a lot. I wonder, for example, if baby grands have shorter pivots.

                      Generally, they do. Concert grands have the longest keystick length and longest pivots. With a grand of fixed length, you only can lengthen the keysticks or pivot if the rest of the piano is shorter, so longer keysticks on a smaller grand would trade off soundboard area and string length to some extent. Uprights do not have that particular limitation.