Lewm, the analog of a friction bearing is not strictly correct. The effects are similar when considering the influence of stylus drag though - both act as a low-pass filter for vibrations and speed variations.
As for a freely spinning platter vs. a constant friction - the latter has actually some nice advantages - motors work more consistently against a constant force (just imagine yourself on a bike peddling downhill vs. peddling against a slightly well defined force. Downhill the change of load makes it difficult to keep speed constant). Of course as always, whether the design will be successful will really in the details of the implementation.
Also, a nice discussion of friction bearing vs. high mass platter by Frank Schroeder can be found here:
Discussion of Friction Bearing by Frank
Dodgealum, sorry if we take the thread somewhat off-topic, but I am hoping the discussion of low-mass and high mass designs may aid you in the decision to find the right turntable.
As for a freely spinning platter vs. a constant friction - the latter has actually some nice advantages - motors work more consistently against a constant force (just imagine yourself on a bike peddling downhill vs. peddling against a slightly well defined force. Downhill the change of load makes it difficult to keep speed constant). Of course as always, whether the design will be successful will really in the details of the implementation.
Also, a nice discussion of friction bearing vs. high mass platter by Frank Schroeder can be found here:
Discussion of Friction Bearing by Frank
Dodgealum, sorry if we take the thread somewhat off-topic, but I am hoping the discussion of low-mass and high mass designs may aid you in the decision to find the right turntable.