Harry is holding a DD motor stator in the above pic, and explained why its design removes any 'cogging' that could be a problem with some early (last century) DD motor/controller designs.
Near Matt's elbow above is a BD Avenger. Matt described the plinth as being 'acrylic/aluminum/acrylic', while Harry's DD Avenger shown below is 'aluminum/acrylic/aluminum', which allows the end user to select various colors of anodizing, such as the red on Harry's, for the aluminum pieces.
We attempted to play "The Good, The Bad & The Ugly" by the Danish Symphony, but there was a feedback problem that we did not have time to correct. We did listen to one of Harry's several RtR machines. I counted five (5) of them as well as many tapes (not as many as LPs).