PsAudio 300?

You should, of course, check the archives, as there are a lot of posts on this topic. I've had one a few years now, which I use for my digital gear without separate power supplies, and I'm very happy with it; blacker backgrounds, lower noise floor the principal benefits. It works best, in my experience, with equipment that does not have a highly sophisticated or regulated power supply (sort of acts as a big power supply for those items, like inexpensive CD and DVD players). One of the few high end products which I've found worth the price asked. I'm also a fan of the Multiwave option, although there are some who believe that the power port option (which I don't have) is more of an improvement than the Multiwave.

I've had mine for almost a year. Wouldn't be without it.

One of the best upgrades in my system! Even better with the MULTIWAVE. Don't go for the cooling fan, though - first: it is not necessary unless you run the unit close to its limits all the time, second: the fan makes noticable noise.
When you go back to feeding your equipment from the normal mains - which I did for experience - you notice the HUGE improvement the PowerPlant does for you.
Highly recommended!
Good luck!

Concur with all of the above. I have both the UO and the P300 with Multiwave, and the P300 is certainly the more dramatic improvement. The multiwave makes a big difference, too. Occasionally I have forgotten and left my P300 in normal 60 cycle mode, and after a short while listening, I can tell something's nit quite right.

You won't regret adding the P300 to your system - I wouldn't be without it!

I have both the 300 and the 600 in separate systems and have been both surprised and impressed with the results. Impressions are similar to those described above. One version will be a must in my systems now...

Just let me know if you have any questions about the systems I use them in, etc or check older threads.

Jacob