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Equipment Review
November 2003

ExactPower EP15A Power Conditioner/Regenerator

by Doug Schneider


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Review Summary
Sound In Doug's home-theater system, "the audio portion improved slightly, but these improvements were subtle compared to those of the video image." In his stereo system, he "noticed an increase in resolution, detail, and dynamics."
Features "An active approach to cleaning up power by regenerating and correcting the incoming line voltage"; "the ExactPower people claim the EP15A will deliver roughly 1300 watts and 15 amps," and it "can spring 46-amp peaks" as well." "EMI and RFI filtering are also built in, in addition to protection circuitry that will shut the EP15A down to protect the components attached to it."
Use "I used the EP15A with both [home-theater and two-channel systems]. What pleased me right from the start is the number of my components I could plug into the EP15A -- all of them, exactly what I wanted to do."
Value "Everything the EP15A did for both of my systems was positive, and that’s rare for any component."

Power conditioners meant for use with high-end-audio components have raised more questions for me than they’ve answered. For example, when it comes to whizzy and expensive power cords, I don’t have to think very long or hard before I come up with a question that goes something like: How much can six-feet of wire between my component and a wall plug really do compared to everything that goes on before that tiny wall socket? Then there are passive power conditioners. Now granted, many of them have a lot more going on inside than do power cords, but did you ever wonder: If the lights go dim as a result of a dip in the line’s voltage, won’t my stereo be affected, too, and can a passive power conditioner actually do anything about that? I don’t think I’m alone with these thoughts.

But all of this is not to say that power cords and power conditioners can’t do something -- most certainly do. I own a few of both and use them because of the benefits they offer. But it’s obvious that something more can be done in terms of cleansing the power to our audio systems or there wouldn't be so many products with their own game plans for combating power-related problems. In short, I don’t find many power cords and power conditioners to be complete solutions, and that’s where a product like the $1995 USD ExactPower EP15A comes in.


The company behind the ExactPower products is Atlantis Power Quality Systems, Inc., and with the EP15A they take an active approach to cleaning up power by regenerating and correcting the incoming line voltage so you get a rock-steady (or so -- plus or minus 1%, they say) 120V at 60Hz to feed your electronics.

The idea of regenerating power is not new. Accuphase has produced regenerative units for years, and in more recent times PS Audio popularized their Power Plants. But while PS Audio’s products were quite a bit more affordable than Accuphase’s, a 300-watt Power Plant today will still set you back $1295, while a 500-watter costs $1995, and a 1000-watt unit goes for $2995. Realistically, 300 watts isn’t enough power for an entire system, making the 500- and 1000-watt models the most practical. In a nutshell, you need lotsa powah, and that costs money.

The ExactPower people claim the EP15A will deliver roughly 1300 watts and 15 amps for a hair under $2000 -- close to the full grunt of your wall socket, which, in my experience, is enough for the majority of systems. In fact, ExactPower says that the EP15A can spring 46-amp peaks should your components demand them. Their trick? The EP15A doesn’t regenerate the entire waveform; it only regenerates part of it -- from 90 volts on up -- and it uses a class-D amplifier to do that. The result is 90% efficiency, low weight, low heat, and a relatively low price.

Keeping the voltage constant is one thing the EP15A does, and correcting for distortion using what ExactPower says are proprietary "feed-forward techniques" is another. EMI and RFI filtering are also built in, in addition to protection circuitry that will shut the EP15A down to protect the components attached to it.

The best way to describe the EP15A’s appearance is amplifierish. It comes housed in a clean-looking, attractive, conventionally sized enclosure. This is in contrast to some power conditioners that are downright industrial-looking. My review sample was in a brushed-black finish, and it looks very good, but the EP15A also comes in silver, too. By audiophile standards, the EP15A looks very nice.

The power switch is centered on the EP15A’s front panel below the display window, with the power-on stage needing a few seconds before the EP15A’s regenerated power arrives at your components. By default, the window displays the EP15A’s output voltage (it only shows you the level of the regenerated power, unfortunately, and not the level of the incoming power), but the smaller button above the power button allows you to toggle the display to show volts, watts, amperes, or nothing at all.

On the back are eight outlets -- all switched through the front-panel power button (there are no unswitched outlets provided) -- and an IEC receptacle for a detachable power cord. I would have to think long and hard, as well as ponder similar questions to the ones I asked at the beginning of this review, before I considered attaching an expensive power cord between the EP15A and the wall. This sort of defeats the purpose, don’t you think?

Overall, the EP15A appears to be well made, and as you’ll find out, it functions flawlessly. The EP15A's warranty is three years, but there is no additional warranty for components plugged into the EP15A (as some companies offer with their power products).

Use and performance

I have two systems in my house -- one home-theater and multichannel-music based, and the other for two-channel listening only. I used the EP15A with both. What pleased me right from the start is the number of my components I could plug into the EP15A -- all of them, exactly what I wanted to do. I hate the notion of plugging half of my components in and then finding out I need another device for the rest.

In my home-theater system, then, I plugged my Nakamichi AV-10 receiver, Sony Trinitron TV, Kenwood DV-S700 DVD player, Sony SLV-67UC VCR, and Mirage LF-150 subwoofer into the EP15A. The speakers were Mirage Omnisats. The more I plugged into the EPA15A, the higher its displayed output wattage -- upwards of 400W were being pulled from it, not too heavy-duty a load but enough to take note of. In the three or so months that the EP15A lived in this system, it worked flawlessly -- there wasn’t a hiccup, glitch, or incident of any kind. Save for the two-day period in August when my home was affected by the blackout that struck a large chunk of eastern Canada and the United States, the EP15A handled all the other dips and surges my system gets bombarded with on a daily basis. The EP15A’s voltage indicator hovered between 120 and 122 the entire time.

As for audio and video performance, both improved, but before I get into that discussion, I want to give some necessary context. What the EP15A does is ensure that your system gets a constant supply of power -- in this case 120 volts at 60Hz. If, for example, your wall socket already delivers perfect power and is devoid of noise and distortion problems, can the EP15A really do anything to improve that? Probably not. However, most people don’t have that luxury. The building I live in is polluted with appliances, and this makes power fluctuations regular occurrences. My comments, then, come from the point of view of having problem power, and my experiences may be indicative of what could happen with the same components being fed pristine wall juice.

And so it was, regardless of the time of day, my system operated flawlessly -- and ideally. I became oblivious to those daily occurrences when, for example, the entire laundry room powers on, or when everyone else’s stoves and air conditioners kick in and my TV’s image would waver and my stereo would sound mysteriously subdued. With the EP15A in place, the laundry room, the stoves, and the air conditioners continued to do their things, but my home-theater system didn’t even budge. That, to me, is worth the EP15A’s $1995 asking price.

The audio portion improved slightly, but these improvements were subtle compared to those of the video image (more on this below), and only noticeable on certain types of material. For example, I have trouble discerning superior airiness or transparency with a heavy-handed mix like The Matrix. And even with well-recorded surround material, like Norah Jones’ Live in New Orleans DVD, any improvements are still hard to hear because the surround effects have a way of taking precedence over the little stuff. It was only with two-channel material (i.e., CDs) that I could hear a tidier top end, and better articulation in the bass, particularly on music with serious low end, like Eric Clapton’s weighty-sounding Unplugged CD [Reprise 45024].

It was with reluctance, therefore, that I pulled the EP15A from the surround-sound system and moved it to my two-channel reference rig. I wished I simply had two EP15As, one for each system, and could have gone from there. So into my two-channel-only system the EP15A went, and out went one of the protective Brick Wall filters along with a Richard Gray’s Power Company 400S I keep around the house. I plugged the Zanden Model 600 tube amp and Simaudio Nova CD player into the EP15A. No fancy power cords were used -- just straight-outta-the-box stiff-black-plasticky ones. The speakers of the moment were StudioLab Reference Ones, which I’m currently reviewing.

Again, the improvements brought by the EP15A will depend on the quality of your incoming power, but just as in my home-theater room, my two-channel room is besieged with bad power. But even with the dishwashers, air conditioners, clock radios, blenders, microwave ovens, refrigerators, and all the other appliances and devices that my neighbors and I have, my high-resolution stereo rig was getting fed clean power -- independent of the time of day. The lights around me still dimmed from time to time, but my system shone brightly -- and in this system, of course, there’s no video, but the sonic differences were more pronounced, likely because this system is of higher resolution -- it’s where I evaluate audio gear, after all.

I noticed an increase in resolution, detail, and dynamics. My suspicion is that it was all most likely a result of lowering of the noise floor. The quiets seemed quieter and the louds seemed louder. The soundstage was laid out with better specificity and a more developed sense of depth. And when there’s less noise, clarity increases.

Here’s how all of this translated with music. The 1999 CD re-release of Willie Nelson’s 1978 recording Stardust [Columbia 65946], for example, showcases the singer starkly in a simple but enveloping mix. I was already impressed with how well my system cast a soundstage -- with a splendid sense of depth -- and how much detail it could preserve, but when the EP15A was slipped in, I heard an even starker, cleaner, and more pristine presentation, with an even better re-creation of soundstage depth. Nelson’s voice, too, had better resolution and better attack. Presence increased, and the musicians became more incisive, dynamic, and detailed.

I’m using strong words here, and although the differences were apparent, they were not enormous, like those heard when changing from one speaker to another, for example. So not huge differences, and that’s likely why I couldn’t discern as much with my low-rez rig, or perhaps that equipment wasn’t affected to the same degree. But to me, the EP15A is a far more complete solution than any other power conditioner I’ve tried. In fact, everything the EP15A did for both of my systems was positive, and that’s rare for any component.


Compared to straight-out-of-the-wall juice (even when running as best as it can in my building), the EP15A made the image from my TV look more vibrant with improved color saturation, and this is the reason I've used PS Audio's $399 Ultimate Outlet. It’s a pretty easy thing to see. Plug the TV into the wall and it looks OK. Plug it into the Ultimate Outlet or the EP15A and you’ll be wondering if someone fiddled with the video settings. There’s a definite increase in "picture punch." Thinking like a tweaky audio/videophile, though, I had to wonder if doubling-up the devices would make for even better performance (i.e., using an Ultimate Outlet and an EP15A in series). In a word: no. One device is good enough, and since the EP15A does so much more than just improve the video image, the Ultimate Outlet sat quietly to the side when the EP15A lived alone in this system

I also noticed that the audio and video performance of the home-theater system never strayed, day in and day out, and that certainly didn’t happen when I used the $199 Brick Wall 8R15 surge filter (for protection of my components) and a PS Audio Ultimate Outlet (for the improvement that it brings to the video image) together. Both of those units have an excuse, though: They’re passive devices that aren’t meant to deal with power fluctuations as the EP15A does. And therein lies the biggest difference between active and passive power devices -- or rather, the EP15A and all the other power conditioners and power cords I have around my house. Passive devices can improve certain aspects -- and they’re usually quite a bit cheaper, as the ones I’m using are -- but if the voltage goes astray, they can’t do much about that. The EP15A, on the other hand, can address voltage problems, and when you experience constant voltage all the times, you don’t want to let go of it.

When I took the EP15A out and slipped a four-outlet Richard Gray’s Power Company 400S in its place -- a passive filter that retailed for $700 in its day -- my home-theater system’s sound lost a touch of transparency, a smidgen of hashiness came over the top end, and the sub didn’t have quite the articulation that it did with the EP15A in place. The picture quality also suffered, so the Ultimate Outlet was slipped back in to feed the monitor.


The EP15A impressed me immensely. It appears to handle power-related issues head-on, leaving me no questions to ask. And although the EP15A is more expensive than any of the passive power devices I have around the house -- whether they are power cords, power conditioners, surge suppressors, or otherwise -- it equals or betters them all in terms of performance. It also has enough juice to power an entire system, and it offers voltage regulation, which none of the passive devices I have do.

The only real criticism I have about my EP15A is that I had only one to work with. I wish I had two, one for each of my systems. But even after living with a single EP15A, I find it indispensable.

...Doug Schneider

ExactPower EP15A Power Conditioner/Regenerator
Price: $1995 USD.
Warranty: Three years parts and labor.

Atlantis Power Quality Systems, Inc.
9411 Winnetka Avenue
Chatsworth, California 91311
Phone: (818) 886-5364
Fax: (818) 886-0504

E-mail: info@exactpower.com
Website: www.exactpower.com

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