Power conditioner + voltage regulator

Power regulator? That would imply a constant current source for a set voltage. Why would you need this? Your system only sinks current as needed. Do you mean a power limiter?

Regenerators like PS Audio and the like are both. As they output a steady 120volts.(and some one can adjust the voltage to what one wants to some degree. The PS Audio P600 and family with the optional board can also adjust the frequency of the A/C current, to interesting effect)

Some Furman power conditioners have a 'power factor' device to alleviate drops in voltage by using a 'stiffening cap' (sort of like the automotive audio type)

Generally unless you have widely fluctuating voltage, you do not need a voltage regulator.
Normal voltage ranges of 115 to 125 volts are no big deal.
Once you are getting sags down to 110V or overvoltage of 130 volts Then you have a problem

And I am certain the heading has the correct question. The body of the op's text is just a mistake, and he does mean power conditioner and voltage regulator.

The voltage at my house hovers in the 117v range. At nite? close to 118+. The day before our SoCal power outage (somebody in Arizona tripped on our extension cord) I noted voltage closer to 112 or 113. In summer during peak demand, I start shutting stuff off around 115 volts.

Generally unless you have widely fluctuating voltage, you do not need a voltage regulator.
Normal voltage ranges of 115 to 125 volts are no big deal.
Once you are getting sags down to 110V or overvoltage of 130 volts Then you have a problem

I agree in general with the exception I've personally noticed with my tube integrated. When the ac voltage varies the biasing on the tubes varies in a direct relationship.