Off-topic: Hi, Mike! Good to hear from you.
I have only one further comment: It is not valid to lump all servo speed correction mechanisms as if they were all the same. Technics was dominant in the DD industry, and they espoused powerful iron core motors driving heavy platters (if we limit ourselves to the SP10 series) and very frequent speed correcting. But other manufacturers, e.g., Kenwood in the L07D, settled on using less powerful coreless motors, to minimize or eliminate cogging, and a comparatively laissez faire approach to servo correction, which means that corrections are fewer and less frequently made. This to my ears resulted in the L07D sounding a tad more "musical" than an unmodified SP10 Mk3. Applying the Krebs mods and now the chip made by JP Jones have made my Mk3 sound a lot better. So, just to say that those designers of the 70s were well aware of trade-offs related to servo control.
In keeping with Mike's critique of the Monaco, I had wondered what became of that product given the initial ballyhoo. One problem with it, in my mind anyway, might be its relatively low mass. When speed corrections are made, there is an equal and opposite force generated at the platter such that the chassis "wants" to turn in the opposite direction from the platter. I think you need mass to overcome that manifestation of Newton's 3rd Law.
I have only one further comment: It is not valid to lump all servo speed correction mechanisms as if they were all the same. Technics was dominant in the DD industry, and they espoused powerful iron core motors driving heavy platters (if we limit ourselves to the SP10 series) and very frequent speed correcting. But other manufacturers, e.g., Kenwood in the L07D, settled on using less powerful coreless motors, to minimize or eliminate cogging, and a comparatively laissez faire approach to servo correction, which means that corrections are fewer and less frequently made. This to my ears resulted in the L07D sounding a tad more "musical" than an unmodified SP10 Mk3. Applying the Krebs mods and now the chip made by JP Jones have made my Mk3 sound a lot better. So, just to say that those designers of the 70s were well aware of trade-offs related to servo control.
In keeping with Mike's critique of the Monaco, I had wondered what became of that product given the initial ballyhoo. One problem with it, in my mind anyway, might be its relatively low mass. When speed corrections are made, there is an equal and opposite force generated at the platter such that the chassis "wants" to turn in the opposite direction from the platter. I think you need mass to overcome that manifestation of Newton's 3rd Law.