Analog Corner #308: PS Audio DirectStream Power Plant 20, Thixar amplifier stands

I'm waiting for a bypass.

My heart did not attack me. My arteries aren't clogged. I'm awaiting an electrical bypass to save my audio system's life.

As I reported last month, my audio system started choking on the house juice immediately upon power up after an emergency power generator was installed in my house. The system isn't running on generator power, but the generator's installation required installing some other hardware in the AC signal path: a switch that automatically transfers the house's power system to the generator when the power goes out. It's that new hardware that seems to be causing the problem.

Before the generator was installed, the sound had been better—more intense and emotionally elevating—than any that I've heard in the almost 22 years I've been in this room. I'd leave the room late every evening laughing, literally vibrating and shaking my head in wonder. I'm not kidding!

I know this sounds like reviewer bullshit, but I'm not stepping in it when I write that every familiar recording I played was like hearing for the first time what was really on the record. Synapse-embedded expectations were consistently shattered. Meaning flooded in as formerly disparate musical threads connected.

Even unsophisticated, raw recordings like The Rolling Stones' Between the Buttons (UK Decca SKL 4852) became a new experience. I now perceived that songs like "Complicated," sewn into my DNA after 55 years of listening, were far more complicated, especially microdynamically and texturally, than I'd previously realized. The fuzz bass on that track shot through me like a drill bit. Charlie's tom hits became massive, splattered thwacks, each more insistent than the previous one.

Recordings I knew were astonishing became even more so. From the day in 1968 when I first played The Moody Blues's Days of Future Past (UK Deram SML 707), I knew the music was arch and pretentious—and the Technicolor sound almost unbearably beautiful, spread across a Cinerama stage. That group—then best known for its cover of Bessie Banks's "Go Now!"—had gone into the studio to record a hi-fi demo disc for Decca's new Deramic ("Decca Panoramic") process, which the label's engineers promised would "allow for more space between instruments, rendering these sounds softer to the ear"—Boy, howdy, did it ever, although not as much on the American pressing.

What I heard on that spectacular pre-generator system was doubly clarified spatially and through the roof timbrally—a much-improved version of a confirmed sonic spectacular. How can anyone sit through a record they've heard for 53 years for 40 minutes going "Wow!," again and again? I don't know how, but that's what I did.

I remember buying that record while home from college for spring break. I'd picked it up at Sam Goody's, because I'd been attracted to the cover art. I bought two other records that day: Steppenwolf's foil-wrapped debut and Blood, Sweat & Tears's Child Is Father to the Man. (Can you remember what you added to your streaming library last week?)

Weeks of eager listening, asking, "Okay, what will that now sound like?" ended when the electricity came back on after the generator installation. I expected nothing to change—why would it? But it did. It had.

Everything good was gone. Transparency: gone. Vivid three-dimensionality: gone. Black backgrounds: gone. Precisely drawn images: gone. Two large, ill-focused boomboxes had replaced absolute magic. The sound was so diffuse, unorganized, and cloudy that I couldn't listen comfortably other than as background filler.

Last column, I went into a few possible explanations of why a transfer switch used to shunt electricity between the street and my listening room might have caused the sonic deterioration. As I wrote there, AudioQuest's Garth Powell (designer of the company's Niagara power conditioners) told me I wasn't imagining things—that he gets calls and emails all the time from distraught customers who have installed generators or decided solar would produce better sound, but it didn't. Some of it had to do with induced noise on the AC line and the blockage of RF noise attempting to return to earth ground.

One industry associate, trying to be helpful, told me to buy a $150 Trifield Line EMI monitor. Just plug it in and the built-in speaker and visual meter will tell you about the noise on your line. The meter, though, didn't read much noise. I asked Powell: Why? Because it's "cheap, inaccurate, covers less than 4 octaves of only one of three induced-noise modes. Its 10-cent switching supply adds nearly as much noise as it often detects....Doing this for real starts at about $8000 for a portable meter." Oh.

I'm still waiting for the bypass to be installed that will route "the street" electricity directly to a new breaker panel that will serve my audio system, bypassing the switch. (I won't be able to use my system when the power is out, but I can live with that.) Meanwhile, were it not for PS Audio's regenerators, I'd be out of business until the bypass happens, which, the electrical contractor told me, will not be anytime soon. They've got generators to install, and in their eyes my problem is hardly an emergency. To me, yes, to them, no.


PS Audio's DirectStream Power Plant 20 AC Regenerator
Jim Austin reviewed this $9999 piece in Stereophile a few years ago. Please read his buttoned-down review—the cautious one you'd expect a scientist to write (footnote 1). There's no point in repeating his description of the product and the technology it employs. After you've read it, read the comments. My favorite is, "A really good amp should not be affected by mains quality at all, or at least as little as possible." So glad this reader was paying attention to what Jim wrote.

I live in a single-family suburban house, not in a city-dweller apartment as does Jim. My electrical service is the first one off the transformer across the street. Whether or not that is a major advantage, I do not know, but it can't hurt. It seems to me I've got "good power"—or did, until the transfer switch installation.

I have had some odd ground-noise issues here over the years. An amplifier I once reviewed, and then bought, developed an annoying grounding-related buzz that no one could diagnose and eliminate—not even a studio-tech guru I imported from New York City. Eventually I gave up and sold the amp, telling the buyer that if he had the buzz problem, I'd take it back and refund his money. He heard nothing but dead silence (and the music the amp produced) and was very happy with his purchase.

I had an electrician friend completely rewire my room's dedicated line, adding 20 amp service. He also pounded a grounding rod into the flowerbed outside my office. Since then, I've heard no buzzing (except when the window's open and there's a bee in that garden outside), but when I used high-quality power conditioners, I could still hear an improvement, blacker backgrounds in particular. Over the last few years I've utilized Shunyata's Hydra and Triton conditioners, and more recently I've used the AudioQuest Niagara 7000, all with good results. A few months ago I added the Computer Audio Design (CAD) Ground Control products, which brought another level of quiet and some other improvements.

Footnote 1: Guilty as charged.—Editor

303mikk's picture

I think people are right to be sceptical about the promises made by power conditioning products, but also open to have their minds changed.

The (sometimes) astronomical pricing, and almost complete lack of published specs from Audioquest/Isotek etc to show what their products are capable of should be enough to make potential customers wary.

Have a look at the published specs of a AU$400 hard-wired product I think would be easily comparable to any $1-2000+ 'hi-fi' product and then try to compare that to a hi-fi power conditioning product.

Added to this, as mentioned, is not knowing if your hifi setup will benefit from power conditioning until after you've paid the purchase price makes conditioning a real minefield.

Only buying conditioning products from a retailer that accepts no-question returns would be a smart move!

My (13kw Enphase micro-inverter based) solar system is being installed in a few weeks, so I'm somewhat concerned about the outcome from this on my hifi, but will just have to wait and see the results...

SET Man's picture


I'm in Queens NYC. And I've been using the P600 bought new back in 2002. I remembered hearing about it when it first came out, "That's a brilliant idea and make a lot of sense" I thought to myself back then. Well, 20 years later it is still powering my system. Maybe someday I can afford newer model. My hat off to Paul McGowan.

RH's picture

...why was the sound Better Than Ever just before the electrical disaster? The whole piece is pushed along by that premise, yet the reason why is left dark, like a mysterious black hole around which the climax circles.

What had Michael done recently that so improved the sound he was left newly dumbfounded?

New tweak?

New piece of review gear?

Curious as to why this is left out.

303mikk's picture

And why 2 PS Audio PowerPlants required?!

Rocketman248's picture

I would imagine it has something to do with the Air Force Zero he currently has in for review.

Jim Austin's picture

... correctly in most cases, that the people who read this column read him regularly. Those who do will be aware of the changes to his system that brought him to this point.

Jim Austin, Editor

RH's picture

...but I don't think it's a good or helpful presumption, actually.

I read MF fairly often and very much enjoy his columns here and at analog corner. However I don't read every single thing he posts, and I'm sure I'm hardly the only one who enjoys his column without being devoted enough to read every post. So I think a reference to what he was actually talking about would have been warranted. IMO.

Jim Austin's picture

It's difficult, in limited space, to repeat much of what has been written in previous columns, but we'll keep this in mind in the future.

Jim Austin, Editor

Michael Fremer's picture

Wilson XVX loudspeakers....true I should have mentioned that!

PeterPani's picture

with 6 mono power amps, three phono pramps, a preamp, a tape machine preamp and several other sources. Where do you stop?

tonykaz's picture

Properly established Clean AC is foundational to satisfying HighEnd Gear performances. Conditioners are modest price point attempts at consistent Clean Power.

Traditionally gear was built with sufficient power supplies.

Now-a-days, our lives are filled to overflowing with electronic noise sources making a dedicated 240 VAC Powerplant a necessity. ( especially for gear evaluaters like reviewers )

We've always had noisy AC, it's nothing new!

PS Audio is the only one properly addressing the issue. ( other than manufacturers that build gear with adequate power supplies )

Tony in Venice

JRT's picture

Interesting problem, and I expect that unraveling that will also prove interesting.

Not sure if running more than one PS Audio Powerplant (instead of running only one) might possibly place associated portions of the system sharing low voltage signal interconnections at excessively different ground potentials during a lightning storm or other surge producing events, possibly damaging the equipment. Can the outputs of those be referenced to one shared common ground?

mixpro's picture

Michael, I found your power related trials and solutions a very interesting read. Seems there's an opportunity for Stereophile to really dig into the causes. Maybe in partnership with an electrical engineer publication? Is there a measurable increase in source impedance? Can this be shown to result in current drops? Is there measurable RFI or other noise on the line? It would be quite interesting to read test results on this plus a comparison when you do get your transfer bypass.

I also agree with comments [303mikk] made. As a reviewer, you're in an enviable position to try out gear and call in favors (and we readers greatly benefit from that.) Most of us don't have try-before-you-buy access. I have an Enphase solar system on the roof, grid-tyed but no transfer/backup. Your power troubles make me wonder about the solar system's effects on our AC line. But I don't really have a budget to drop $5k just to see if Niagra 5000 makes a difference, or $10k for a regenerator. So I'm left wondering.

LemonCurry's picture

That switch is not some inert slab of metal. There are electronic components monitoring your service and throwing the relay when an putage is detected. I'd imagine every bit of distortion you are seeing will be exactly the same when the generator comes on. Having once designed circuit boards, if one isn't being proactive about controlling noise, you'll have plenty of it. I'm gonna go out on a limb and say the electronics in your power backup system were not designed with audiophiles in mind. I think unless you get isolated service to your listening room, you'll probably need to hang on to those power regenerators.