Some turntables already have a "conditioner" as part of their drive system. Turntables that generate a signal for the motor to run on would not benefit from a "conditioner" The AC lines frequency is held to very tight standards. Turntables with plain AC motors operate on the lines frequency. A regenerator might improve measured performance slightly, but you would never hear the difference. Turntables like my Sota use a three phase motor and drive it with a phase converter that has adjustable frequency. The computer then controls turntable speed by reading a magnet on the bottom of the platter. You can also tell it what speed you want it to run if you want to adjust pitch. A conditioner is worthless on a turntable like this because it is already doing the conditioning.
It is much more important to spend money on better speakers or if you really want to blow your mind digital signal processing.