Adding this product is the single biggest improvement that I have made to my system.
Everything sounds cleaner and more detailed. Vocals and pianos sound incredible. No "Tiz or ssss" on the vocals, instruments and vocals are clearly defined in the sound stage. I am hearing little nuiances in the music that I never heard before.

I also own the Audio Power Wedge Ultra. The Ultra is also an excellent product, but the P300 is in a league by itself.

Just some follow up points for my review: I'm now running the transport, the DAC, a 150W amp, and a 250W amp (for sub). The power rating on the P300 is only up to 110 during normal listening level. Also, I found the 70Hz setting to be the most natural sounding. It opens up without being too detailed and artificial. An even better product than I thought.

I have received the Power Plant 300 about 6 weeks ago. Before that I was using Monster 3500, and did not have any complaints about it. In any event, I thought that I have a pretty well sounding system with B and C class (as per Stereophile) components. Nevertheless, after reading about Power Plant's principle of operation I decided to give it a try. Because the dealer offered a 30-day money-back guarantee, I figured I can't lose. It is obvious that a device that generates pure AC is by definition better than any filter. The question is how much
it actually affects the sound. What I most care about is the realistic
sound and lack of noise. I listen to live performances often enough
to dislike any changes and colorings created by sound reproduction
equipment.

For starters, I have connected PP 300 to all my components, including the
2*225W/Ohm power amp. With volume being set at 0, power consumption was ~130W. When I have reached my customary volume level for Jazz, consumption increased to 170-210W. At 260W volume was beyond
tolerable. Symphonic music requires 250-270W for normal volume, which is a bit above recommended load for PP300. Still, it did not overheat.

Here's what PP300 did for my system:

1. Noise is practically absent.
2. Bass is much deeper, sharper, more realistic and accurate.
3. Mids are more transparent, and musical instrument separation is better.
4. Highs are cleaner and livelier.
5. Power amps heats much less.
6. Turntable works much better.

The chief conclusion I made after using PP300 after the first listen -- my system is much better than I thought.

PP300 deserves the highest grade, and may be gives some of the best improvement per dollar spent.

PS I have found www.audionut.com to be the best place to get it from --
free shipping (saves you ~$40) and a free gift... Dealer is very nice
guy and highly competent professional. He gave me some advice than not
only improved my sound but also saved me some money as well.

Similar Products Used:

Panamax and Monster Power surge supporessors/AC filters

Virtually noise-free, much more musical, vocals fleshed out,
improves system without side effects.

Consumes a lot of power due to heat,
power limited to under 300W (P300).

This is absolutely a must if one is to get the best out of his/her existing stereo system. I have never been happier: The P300 improves every aspect of my modest system (around $7K) significantly due to a much lower noise level, for one thing. It does that consistently; no matter when I feel like to listen to music, I always get the same high quality sound. Of course there is more neat stuff to play with such as adjustable power factor (output frequency).

Since I got the P300 I stopped thinking about which component to upgrade next. Instead I found myself buying more CD's and DVD's. Simply put, this lovely piece just lets me enjoy music from my existing system. My system now sounds like a much more high-end setup, very musically satisfying. The best value in the high-end, period!

Similar Products Used:

Chang LightSpeed,
Monster HTS2000, PAC IDOS

It works as stated.

Does get hot, but apparantly that is not a concern.

Agree with the rest of the posts. My first impression is one of immediacy in the sound, just seems a bit more there. It also allowed me to remove a cheater plug on my CAL Cl-15's AC cord which I had to previously use to eliminate a buzz due to a ground potential problem. Once I hooked up the PP 300 I no longer needed the cheater plug. Every thing seem a bit more dynamic.

Similar Products Used:

None really (had a so-so Panamax Surge strip)

Improves performance in every aspect

Odd shape, runs HOT

After 2 years of continuous optimizing of my system, this was just a further try, based on the reviews below (No chance for an audition in Switzerland) - I simply ordered the P300 in the states.

This was a very good move. None of the statements below is exaggerating. Improved overall performance tremendously on the spot. I run the CD Transport (Sony), preamp (EAD Ovation), DVD (Denon 5000) and the Digital Correction Device (Canton Digital 2) from the unit. I would love to connect my power amp as well, but this one's a little bit oversized (EAD Powermaster 2000)- definitely needs a P1200 ;-)

Using the P300, the immediate result was a highly improved smoothness of the sound. Violins had at last that special timbre. Bass was further well defined. Not a tremendous improvement reagarding the sound stage - but nevertheless an improvement. I run the unit at 60Hz - anything above that won't improve the sound much further - would even say it would then loose some of its smoothness.

The unit runs very hot - and I never switch it off (Who cares if it doesn't blow up). It can't be placed in any rack, too, it is simply too long.

But this are disadvantages you would love to live with -
once you have heard the imporvements (Never thought that the power supply alone could make SUCH a difference).
Get one, switch your room heating a step down and enjoy the music.

Mike

Last year I had this idea: Why not use an Online UPS (uninterrupted power supply) for audio applications? This idea was quickly forgotten when I found out about the room requirements and the cost of those things. I figured I'll just have to wait until someone comes out with a layman's version or make one myself in the future. Then a few months later I heard about this new design in AC treatment from an amp company, but this time the unit generates power using DC convertion. The unit is a converted power amp. Sounds familiar? Well, they also enable the user to change the frequency mode. Ok, that's great but all for how much? Less than 1K?! These people must not be making much profit out of this (in the beginning at least). Full 30 days money back guarantee? I got the unit a month later.
Now keep in mind that I had recently sold my high end music system and now is trying to built a decent budget system. This IMO, is better than my previous system in certain areas. I have now completed everything except for the DVD or SACD transport (waiting for the new digital standard). The following components are used along with the power plant:

AA DTI32 Pro
MSB The Link DAC
Sim Audio Celeste I-5080 integrated
Newform R630, Dynaudio Contour 1.3 mkII
PS Audio Power Link power cords
Harmonic Tech Pro-9 Plus, Tributaries SP4 speaker cables
Harmonic Tech Truth Link interconnects

The manual says to remove all ferrite clamps but I find them beneficial for digital components. I use the Power Link AC cords on my amp and from the P300 to the wall. The Sim amp is 80W@8 (30W above the recommended rating) but the power meter on the P300 only shows 90W with all components connected at the loudest musical passages I can stand. This is a good sign since I'm not about to spend $2K for a P600. As for the frequency mode, I've heard people complaining about the increase of hum coming from their amp's power supply. In my case however, since the amp already creates an audible low hum (at about 1 feet away), when the frequency is raised it becomes higher pitched and thus less audible. So this is actually an improvement on both sides.

To make a long story short, I am utterly amazed to hear that all of the improvements that the manual claimed are true! For the first time I can safely say, "no snake oil or BS here. The change is an improvement." That is when it's run on the 120Hz setting. Much of the improvement is attributed to transparency but the overall result is simply amazing. Brass instruments in particular sound very realistic. Voices become cleaner and more defined. Strings have more presence and resolution. The only other component that managed to create a similar improvement is the costly Audio Alchemy DTIPro 32. But the degree of improvement with the P300 is even higher, and it's useful for other purposes. This is a rare one component upgrade that improves everything without compromise. It doesn't filter anything out of the signal. It simply recreates it. The term "lifting the veil" should be used for this device only. Then again I guess PS Audio is cheating since other components have more problems to solve, not accounting taste differences.

However, despite all these improvements, I do notice a slight slowness or averaging of the music as compared to the AP Power Pack II. I attribute this to the fact that my ears are not used to hearing smooth transitions from one passage to another. It is continuous without any interruption or agressiveness, so my ears are much more relaxed. I noticed that I can listen to hard musics longer than before. Another reason could be the use of an amp that's 30W higher than recommended. Not enough power reserve? Shouldn't be a problem if I don't listen higher than 35W per channel. I think it should be able to handle a 100W integrated without shutting down. But audiophiles may disagree. Anyway, this minor detraction is gone after a few weeks. Maybe I got used to it.

Conclusion: This is a very recommended component. Heck, if you're willing to pay above a grand for a power conditioner, why not get a power generator for less? If you're planning on buying a real AC remedy, this is the only way to go. Otherwise, the cheap models from Monster Cable should suffice. They're well designed "conditioners". I would get a power plant as the first component when building a high end system. Unlike other components, this device can only improve. So you can leave it alone and concentrate on the weak links. By the way, the built quality on this thing is superb. They also use an impressive 3 box packaging to ensure safe arrival. If there is one thing I'd like to complain, it's the manual. I wish they had put a lighter colored background to make reading easier. I felt like reading an art exhibition brochure. There is also no spec section in the manual. Anyway, I am completely and utterly satisfied.

I hate to give 5 stars but this time there's no choice.

Focus, separation, dynamics, low noise

Runs hot

Echo all positive comments. Best balance seems to be around 80 Hz. 120Hz was just too bright - maybe it's telling me something about my system. Don't hesitate - PS offers 30-day home trial. You only pay shipments.
This is not a trivial upgrade. I'm already saving for my PS-600!

Similar Products Used:

None

Starts a whole new class of audiophile power equipment that will change how we look at power forever.

This unit is big! Deep that is -at 19" and had to be placed behind my equipment rack.

Well add me to the list of those who are singing the praises of this product.
I'm stunned over how it has improved my system. I recently had my local audio store let me try an Audio Power Ultra- only to return it after I could not hear an improvement. From the moment I hooked my preamp,transport,DAC and Logan speakers to the Power Plant, I was floored by the clean sound, lowered noise floor and better transient response. If you were on the fence over whether a Power Plant would help your system reach it's potential- jump to clean side of AC and try one. I only wish there was a model cheaper than the 600 that had more outlets and could accept a large amp.

Similar Products Used:

Audio Power Ultra 115

Makes sound clearer

Gets hot and big bill

The first time I noticed system sound enhanced was when I got Newformresearch R645 speakers. They are excellent ribbon speakers. The next is this ps audio power plant 300. My wife noticed it right away. She said she can't find big difference between all modes, but having it or not is a big one. We compared with it and without it the next time. Everthing's got clearer. I am not a sophisticated listener. I am not so pick about the sound. But, It's just different. I bought it from a person who sold it for paying taxes. It has multiwave and fan upgrade kit installed.

My only complaint is that it doesn't have standby mode something like that. So, I have to either keep it on or turn it off/on all the time to save some bucks. Letting it turned on makes me nervous because it gets hot and feels like it takes electricity while idling. To turn it off/on also is cubersome because I unplug all the plugs and plug them again to prevent any possible surge to the devices.
Anybody to advise me on this?

Even with this problem I will keep it as long as I can.

My other systems:
Thule CD 100 spirit
Sim Audio Moon I-5 Integrated Amp.
Newformresearch R-645
Analysis Plus Oval 9
DH Lab BL-1 interconnect