The rumble is masked by surface noise when a record is played. As we all know, unheard vibration can cause audible effects elsewhere.
The fact of this vibration getting into the signal matters, I would think especially at higher volume.
It is irrelevant what I should or should not do when placing my stylus on a plinth mounted cleaning device. The fact of the rumble remains.
The vibration is clearly low-frequency. That's why I suggested you would need speakers capable of some bass. Also, since this noise is pretty low level, you'd need, in all probability, to turn up the volume to hear it well. I listen at pretty high volume but this noise can be heard (but only with the belt in place!) at low levels, also.
If you tried this test on your "custom" HW-19 with negative results with the drive belt connected and turning the platter and the needle resting on something attached to the plinth but not the platter, like a stylus cleaner, and your speakers reproduce 60hz signals and you tried the gain at high, then I conclude that my problem is solvable with a motor that has less vibration.
This is what I am trying to determine before putting money into it.
The secondary question, then, becomes what motor can I get at reasonable cost that has lower vibration than the standard Hurst 600RPM motor.
The fact of this vibration getting into the signal matters, I would think especially at higher volume.
It is irrelevant what I should or should not do when placing my stylus on a plinth mounted cleaning device. The fact of the rumble remains.
The vibration is clearly low-frequency. That's why I suggested you would need speakers capable of some bass. Also, since this noise is pretty low level, you'd need, in all probability, to turn up the volume to hear it well. I listen at pretty high volume but this noise can be heard (but only with the belt in place!) at low levels, also.
If you tried this test on your "custom" HW-19 with negative results with the drive belt connected and turning the platter and the needle resting on something attached to the plinth but not the platter, like a stylus cleaner, and your speakers reproduce 60hz signals and you tried the gain at high, then I conclude that my problem is solvable with a motor that has less vibration.
This is what I am trying to determine before putting money into it.
The secondary question, then, becomes what motor can I get at reasonable cost that has lower vibration than the standard Hurst 600RPM motor.