A Turntable History Question

In my book, it is London to a brick it was an SME Model 30 turntable, except for the date!  The Model 30 was released in 1991, not 1981.

The Model 30 was SME's first commercially released turntable, and it cost megabucks (well 9,000 quid in 1991!).  Weighing more than 42-kgs the table featured a suspended sub chassis, hanging from four pylons like a big-top circus tent.  The pylons each had 15 rubber rings and were also fluid damped.

@wbs

I stand corrected!  The SME website for the Model 30 series two states 60 rubber rings, plus one to counteract the pull of the drive belt, plus two spares!  Of note is the fact that these rings are clearly visible.  Rubber is an elastomer with some self-damping, but additional damping was built into the suspension towers.  The designer aimed for critical damping, so if the deck was pushed down and then released, it would return to the equilibrium position with no overshoot.

@wbs 

I could never afford one, and I did stand corrected! I have found references to 10, 12 and 15 bands per tower depending on the series!

To me, using rubber to suspend a turntable makes perfect sense.  I had thought of suspending mine from the ceiling using bungee cords ... but it was a fleeting thought.  Suspending dynamic loudspeakers on the other hand makes no sense to me because there is nothing to resist the reaction of the cabinet to the movement of the cone.  When the cone moves forwards the cabinet moves backwards which muffles the overall sound.

Using a rubber band to connect a drive motor to a platter seems equally implausible to me - are such bands made so they don't stretch much?  I note SME's recommendation that the Model 30 drive belt should be replaced every 1000 hours (series 2) and also that the bearing should be run in continuously for a month, which is more than half the life of the belt!