The Fifth Element

Long experience has convinced me that many audiophiles' stereo systems substantially underperform compared to what they could sound like. This is not because people haven't spent enough money on their electronics or speakers. Instead, people aren't getting all the performance they've paid for because they haven't devoted enough attention to all aspects of the initial setup, and/or to maintenance and updating.

Reduced to its essentials, a stereo system is a machine designed to convert the electricity that comes out of your wall outlet into mechanical motion by the loudspeakers, which create the sound in your listening room. So we should start with the wall current.

Ayre Acoustics L-5xe line filter
Line filters, power conditioners, or whatever you want to call them are a controversial subject. Many audiophiles claim that the best line filter is no line filter at all. Others claim that line filters merely make the system sound "different" rather than more accurate. Part of the problem may be that the technologies that remove noise, especially high-frequency noise, from the wall current can have the undesired side effect of reducing the amount of electrical current instantaneously available to the power amplifier. Water flows a lot more slowly out of a water purifier than it does from a faucet.

Until I began writing this month's column, I hadn't given much thought to the fact that while countless companies make amplifiers, preamplifiers, phono stages, and digital gear, as far as I know, only one of them—Ayre Acoustics, of Boulder, Colorado—also makes its own power-line filter (footnote 1). Something to ponder. Could it be that most high-end audio companies don't think they have the expertise? Or do most companies think such filters unnecessary? Or not profitable enough?

Ayre's L-5xe line filter is as handsomely designed and ruggedly built as the rest of its products. The case, which measures 17.25" wide by 2.38" high by 13.75" deep and weighs 12 pounds, has essentially the shape of a 1RU (one rack unit) piece of professional gear—except that the L-5xe has no provision for rack mounting. The case is borrowed from Ayre's P-5xe phono stage. That, Ayre's Charles Hansen tells me, explains how the product came into being: Ayre's UK importer was so taken with the looks of the phono stage that he begged Ayre to find some other use for the same housing.

The front of the L-5xe has a centered, vertically oriented oval recess that contains a small blue pilot light. There's nothing else on the front panel except a silkscreened Ayre logo. On the rear panel is a centered IEC inlet flanked by four individual outlets—that's it. There's no master power switch or provision for remote control. The price of $1500 doesn't include a generic power cord. Ayre's own, quite heavy, 1m cord costs $850. Cardas Audio is the OEM supplier of Ayre's own interconnects and speaker cables, so I assume they make the power cords as well.

Ayre's design philosophy for the L-5xe was "less is more." Hansen believes that the controversial nature of many power conditioners is a result of the designer's having let the perfect become the enemy of the good (my phrase, not his). He claims that many power conditioners have more net negative than positive effects on the sound, and that taking a power conditioner out of a system often results in better sound. (It's important to point out that I'm discussing power conditioners, not surge protectors, which are a different and even more problematic kettle of fish.) The L-5xe was developed with a view as much toward avoiding negatives as achieving positives. The basic design brief was to turn high-frequency energy coming in through the power line into heat before it can cause distortion in the audio signal.

Unusually, the outlets at the rear of the L-5xe are single, not duplex types because Ayre claims that it's impossible to isolate the grounds of a duplex outlet. They want the power going into each device connected to the L-5xe to be separately grounded as well as separately filtered. I assume this is why they don't designate an outlet for digital components—the design is such that there should be no leakage between outlets.

The internal wiring is 11.5 AWG; Ayre claims that there is no current limitation. There are no ferrite-containing devices inside, and all contacts are rhodium plated. Ayre is not specific about its circuit design, and doesn't state whether it employs cryogenic processing. What Hansen does say about the circuit is that the high-frequency energy on a power line can't be blocked or shunted to ground, it can only be turned into heat—and that Ayre's nonferrite means of accomplishing that is a trade secret.

Ayre recommends that the L-5xe sit on wood blocks on a hard surface or spikes on a carpet, and encourages a break-in period of at least one week; they caution that, before break-in, its immediate effect on a system's sound may be suboptimal—in their word, "murky."

I installed the L-5xe (on cedar closet blocks) in the system I wrote about in August: Parasound Halo CD 1 CD player, Bricasti M1 DAC (Nordost Silver Shadow S/PDIF cable), Unison Research S6 tube integrated amp, and Opera Callas stand-mounted speakers, all connected with Cardas Clear interconnects and cables. Ayre provided two power cords; I used one to plug in the L-5xe, the other for the Bricasti DAC.

Sure enough, the immediate impression was suboptimal. My reference track was Lucia Popp's delectable recording of the aria "L'amerò, sarò costante," from Mozart's Il Rè Pastore (CD, EMI CDC 7 47019 2). The highest highs were obviously rolled off. Images were less well defined, more like blurry nimbus clouds. Had I not been assured that this would not be the end result, it would have been quite disconcerting.

Still, some positives were immediately apparent. The soundstage depth seemed to extend about 2' farther back and 1' farther forward than before. The soundstage was also taller and wider, although the boundaries of those extensions didn't seem as well defined as the improvement in depth. I found this remarkable—primarily, all I expect from a power-line filter is a lower noise floor and greater retrieval of detail in the time domain.

By the third day, the soundstage was even taller, center images were recapturing their proper outlines, and the highest frequencies were on their way back. However, it was not until two weeks (not one) later that the highs returned as much as they ever did.

At first, it seemed that the highs had lost a little sparkle, but listening to several different recordings of the second movement of Mahler's Symphony 6, with its prominent triangle and cowbell parts, made me rethink that. The harmonics in the high-treble "air" seemed to be more organically connected to the fundamentals than before. There might have been slightly less high-treble energy overall, but the treble was sweeter, and made more of a contribution to my sense of a larger soundstage. I can't report any noticeable improvements in resolution, but it was already a hugely revealing system to start with. Without question, the L-5xe made the system more listenable, and with no trade-offs.

I think that Ayre's L-5xe clearly brought the performance of my system up to the next level. I also think that the timbral balance in the "air" region is now right where it should be. Highly recommended.

Housecleaning Time!
Here's a quick punch list of things that almost certainly will improve the sound of your system for not much money. Most systems suffer from bottlenecks that prevent you from hearing how good your components can sound. Each bottleneck might itself account for only a small, perhaps nearly imperceptible veiling of the sound, but add them all up and the total degradation of your system's performance might be substantial, and especially if your system has been in place for several years: Corrosion or oxidation may have taken a toll on connections and wires.

Shunyata Research SR-Z1 wall outlet
Unless you've replaced the wall outlet that your system plugs into within the past few years, that outlet is probably long past due for replacement—especially if you can look inside the outlet and see drops of dried wall paint. Even if the outlet hasn't been painted over, upgrading to a heavy-duty, cryogenically processed outlet will remove major bottlenecks in both the outlet and its connections to the house wiring.

I think that nearly all home-stereo systems should be plugged into only one wall outlet. This avoids potential problems that can arise from two outlets being connected to different phases of the incoming 240V power after it is split into two legs of 120V, or from remote outlets having different ground potentials. (Of course, this will not be practical with systems that include extremely high-powered amplifiers, or whose amplifiers sit at the far end of the room from the other gear.)

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Footnote 1: Boulder-based PS Audio also makes digital and amplification components, as well as power-line accessories and AC regenerators.—Ed.