What are my options for voltage regulation?

I have a BPT-2 Ultra power conditioner that I am using in my living room system for all equipment. It handles everything pretty well. But I have a headphone amp from Germany (tubed) that is very sensitive to voltage anomalies, of which of course there are many at many different times of day. I have been doing some research into a power conditioner that provides voltage regulation and have read about the Monster, PS Audio (older and new Premier units), and, I think Exact Power units that can regulate voltage. Any opinions on these various units, or on others I don't know about? I guess I would sell my BPT Ultra if the voltage regulating unit can also condition power, but if there is a small unit with only one or two outlets that regulates voltage, that would be ideal. I haven't discovered any--have you?
I have not, Sarah- the Monster (AVS-2000) is a monster; think big heavy power amp size.
I have some issues in summer months when peak demand outstrips available power. This anomaly wreaks havoc on my preamp. I have an Exactpower EP15A power conditioner, and I love what it does to improve the sound of my system.. It is part regenerator and part power conditioner.

I have been considering an APC S 15 or S 20 for the preamp section. This unit contains a built in battery back up to maintain a 120 volt output. I am hoping that this supplements my power during peak usage hours.
Thanks for the input. I think I'm going to go with the PS Audio Premier, it's more compact than what I'm using now (BPT-2 Ultra--HEAVY at 60 lbs) and provides voltage regulation which is apparently what sent my tube headphone amp off into hummmmm-land. I found a dealer who will accept the BPT-2 in trade for the Premier. I wish there were something smaller but this is a lot smaller than the old PS Audio power regenerators.
Checked out your system(s). Girls gone wild ;--) ? I would advise hanging on to your BPT (if it has enough outlets) in order to provide balanced power for your front end stuff. Plug the BPT and your amps (and any other front end stuff) into an Exactpower EP-15A.

Avoid anything with the initials PS. Since you're a lady, I won't even suggest what they might stand for ;--) However, there are a few threads here on AgoN comparing regenerators. AND, exercise 'due diligence' -- read manufacturers websites carefully and thoroughly -- all will be revealed (and if not, come back here and ask questions ;--)
I ended up with the PS Audio Premier because the dealer gave me a good price on a trade in of my BPT and I couldn't get a comparable deal on an Exact Power unit. I just hooked up the Premier last night and I really like it! It's much smaller and lighter than the previous PS Audio conditioner I owned (P-300) and is utterly silent. I am told a fan will kick in if the unit has to work hard but it is not having to do that in my living room system. Voltage is steady at 120 and sound is very smooth and detailed. I hear no rolling off of any frequency, just music. So far, this fills the bill. Thanks for the input.
Yep, PS Audio Premier is an awesome product and trumps ALL current regenerators. If you try one you will see the light!!! It takes a long time to burn in 500 hours but its worth every penny.
Well, it's the old story, you get what you pay for:
BTW,without you knowing it,I am reporting that your EP-15a listing(Nsgarch too) aided me in getting one! I included the Exact Power Ultra-Pure to go fully balanced. THIS combo is the the biggest improvement I have made to my system in a long while! Stuff like vta/azimuth/downforce changes are WAY more obvious with super clean A/C, and I'll bet many folks don't know how much more can be had!
Best regards!
SC53, what have you plugged into your Premier? I've had fan noise problems with two different units. My first one was not to bad with just music, but when I used my TV as well the Premier went into a higher fan speed that was ridiculous. My second one stayed in the lowest speed, but it's lowest speed was much louder than the lowest speed of the first one. In both cases the fan was constantly on, in spite of good ventilation. Did you discover something to minimize the fan noise?
I have no trouble with the fan or fan noise on my PPP. There should be no audible noise. Mine is very quiet even under heavy load. I guess I got a perfect unit. On the PS Audio site there have been some faulty fans reported but PS Audio will gladly fix it for free.