Jet Sound JS-71 - Pretty Maids - Future World

This is my JS-71 Crimson (Cherry)
Video recorded with an iPhone 13 at 1080 30fps
Song is Future World by Pretty Maids 1987

Cherry is missing all of her slide knobs. I'm considering designing and 3D printing replacements. I don't know of any other options. Why would someone remove them?

This EQ may be an example of a difference in quality control or maybe it is just based on the fact that this series is 40-45 years old as of 2023 and some have degraded more than others. (I'd like to re-cap them and see if the sound quality improves, although, in general they all sound good.) Cherry hits hard! I can feel the bass in my body and the floor of the house and the output is crystal clear even fully lighting the last LED.

There is a very noticeable deference between this EQ and some of the others. I've noticed some differences between others but none have been this striking. I may eventually compare them all with the same song.

If you like this song and are interested in Pretty Maids you can purchase the album here - https://a.co/d/fBMxJwV

Pretty Maids Home Page - https://prettymaids.dk/index.html