AC Line Cords - Final Thoughts
Article by Bill Gaw
Hello fellow Audiolics! Welcome to another meeting of Audiolics Anonymous, our support group for the insatiably
tweaked. Have we done any listening this month, or have you been spending most of your time tweaking as usual?
This has certainly been an interesting month for me, both in and out of audio. First, I received several letters from Kalman
Rubinson of Stereophile magazine, one of my favorite audio reviewers, in response to last month's column about Audiology exams. An excerpted appears below:
"In addition to your valid criticism of the standard audiology procedures, let me add two more.
1. The frequencies should be presented in random order and with random ear selection. This would avoid the anticipation/expectation factor that may bias results.
2. The tones should be warble tones to prevent, as you note, the influence of a punctate loss affecting the overall recorded
results.... In addition to your objections to the accuracy of your audiology testing, let me add that you described the test as having been in frequency order from low to high. This means that there's an expectancy effect which biases the results. The frequencies should be presented randomly and with random ear selection. In addition, to rule out punctate losses inordinately biasing the results, warble tones would work better than pure tones, presumably sine waves.
All of his points are valid, and I thank him for his kind words. He also suggested a superb method for testing your hearing in your own home using an audio CD produced by
($24.95, review by Kal Rubinson in Stereophile, Vol.23 No.1, January 2000). With a CD player and good headphones, this disc will allow you to do a better job than your Audiologist's $100 evaluation. Thank you
The next day I received a letter from Juri Krasilnikoff of Denmark, Sweden, about my articles on using a home theater PC for audio and video reproduction in high-end systems. It amazed me that someone in Sweden would be reading my articles and asking me for expert advice, but then again the Internet is a worldwide phenomenon and you don't need a library pass or a subscription to get all the information available. Sadly, I really do not have enough time to answer this type of letter, but have added it below for any of my readers to possibly respond to him.
We're working on a HTPC system of our own. "We" being two programmers… poor audiophiles. The hope is to make a remote controlled system with integrated GUI, so the system can work as a standalone unit with a complete user end interface. Since you have more actual experience in the video/audio performance field it is our sincere hope that we could get a few pointers from you. Video: First issue ... software versus hardware mpeg2 decoding. I wondered if you have had any chance of comparing hardware decoding (i.e. Sigma Designs and the likes) with your high resolution Geforce software solution. Recently the Sigmas chipsets for the PCI are becoming very interesting regarding price versus performance. It can reportedly deliver 1600x1200 pixel video quality. Whether this is better than raw high resolution from software decoding remains to be tested. So its just a plain simple
question of which way to go?
In your articles you have primarily discussed products from M-audio, which undoubtedly are interesting. But i wondered if you have tried/considered a product like: (which has a RIAA btw.). As for our experiences so far, they are limited as our funds are indeed small, the primary concern for us is working on a financial backer so we can throw the time needed into the process.
Unhappily the past two weeks I have been laid up with a kidney stone and surgery, which did have a bright side. First, I now have a greater appreciation for treating quickly and thoroughly my patients' pain. Second, it gave me extra time to experiment with my system and tweak it to the fullest. Finally, I actually spent quite a bit of time listening, which may be a sin for a tweaker, but was actually rather enjoyable. Even my wife enjoyed the music as she said I did not do as much swearing compared to when modifying the system.
(Editor Steve says: Due to Bill's illness, the third benefit is Bill avoided
my visit to his home. Note to self: Reschedule visit to Bill's)
My prize find for the month for software is a group of 4.0 SACD recordings produced by
that are primarily remastered quadraphonic Philips recordings from the 1970's direct from the original master tapes using the original recording equipment and engineers where possible.
A.J. VandenHul in Europe and Telarc in the USA distribute these recordings. I have purchase six of them so far, and all but the Schumann (which is pretty good) has excellent sound and superb performances. Unhappily, you will have to wait for a future column for the reviews, as I have to finish this month's column on AC cords.
Why unhappily you may ask? Because our editor asked that we decrease cord reviews after I had already gotten several types in for review. Also I hate reviewing AC cords for several reasons, the major being that each is system and component specific in effect. But I do have interesting findings
that needed to be shared. I have (?hope?) to have finalized the AC side of my system. Yes, for the first time in 25 years of experimenting, I may have solved my AC problems! If you want to read about my journey, please go the
archives site and read AA Chapters 3, 15, 25, 30, 35, 44, and 45. That should take several hours and a few cups of your favorite beverage. After experimenting with line conditioners, isolation transformers, capacitor banks, AC-DC-AC power supplies, and even batteries and multitudes of different power cords, have finally settled on a configuration that allows me to listen to my system any time of the day or night with pleasure. While the system still sounds a smidgen better at midnight compared to three in the afternoon, there may still be some room for improvement. Still, the difference is not enough to concern me. I am a content audiophile and do not know whether that is a sign of mellowing due to age or I have actually reached audio nirvana. Call it contentment. So I promise this will be my last word on the subject (until something better comes along).
(Editor Steven says in good humor: Anyone want to place their bets now? Current odds are 3:1 we get more power articles before January 2, 2004. Just kidding Bill. Really I am. Put down that power cord! Noooooo…)
Nirvana has been obtained even though I had a recent setback in AC line noise. For about a month I have had a very high frequency intermittent very low volume squeal coming from the tweeters. While almost below hearing level, after a while (like an itch), it bothered me enough to evaluate it and realized it began after we had a new 600 foot deep well and pump installed for our new heat pump HVAC system. It was the well pump feeding back RFI through 650 feet of cable to my electrical service. Unhappily my wife would not allow me to turn off the HVAC while listening to music. Happily I was even able to get rid of this nuisance noise with my new configuration that instilled confidence that I have finally solved my AC woes. Unhappily, have not been able to settle on one or two power cord types, as each seems to have strengths and weaknesses that necessitate different cords for different pieces of equipment. So, how is the AC input set up to achieve this contentment, and what has it cost besides 20 years of experimentation and aggravation?
First, had the electric company come a couple of years ago to evaluate the lackluster AC I was receiving and they graciously replaced both the power transformer outside of my house and some sort of switching panel up the road. This got rid of a lot of grunge coming into the house and stabilized a voltage problem I was having (at no charge). I suggest this and possibly talking your electric company into putting in your own pole transformer as your first step.
Second, I had a separate 50A feed brought into my media room feeding directly off of the top circuit breaker at my 200A service. I also had them change the circuit box configuration to put all motors on the other leg of the 240V line. The box in the room has four 30A circuit breakers feeding separate supplies to left, right, back, and then other non-audio/video equipment in the room. This came to ($1,200) and should cut down on some interference from other noise producers in the home and maximize the amperage going to your equipment preventing current sag.
Third, I recently had to have a new 600 foot deep well put in ($8,900) to which I clamped my house ground ($4). It is amazing what a difference this made over the standard 10-foot deep ground I had from the electric company. The $4 expense counts in the grand total.
Fourth, a year ago I added three Sound Application CF-XE 12 outlet line conditioners ($5,000 each, see AA Chapter 25 and 30) feeding the video components directly, and the audio components
Fifth, added three Walker Audio Velocitor power line enhancers
($3,600, AA Chapter 44) from which I run all of the audio equipment. The combination of these two types of equipment significantly increased the isolation of my system from the super-audio frequencies coming into the system both from the house and the electric line.
All this comes to a grand total of $27,004 so far. Perhaps I should have been content with a Japanese receiver and Bose loudspeakers? All of this just to get decent power to the equipment! You would have thought that with all of this AC equipment and expense I would have the purest 60Hz sine wave voltage and amperage entering my system possible. Sad to say, some grunge still comes through with the cheap power cords usually supplied with equipment and this includes the 4 gauge high purity copper AC wiring running from the junction box. Fact is, junk still gets into my system. This shows up as damage to the sound stage with loss of clarity and the illusion of wholeness, smearing of transients leading to soft bass and (especially with digital) the irritating highs. Power cords add another level of isolation from the grunge.
Thus (finally) we get to the meat of the article -- AC specialty line cords. This is where I have spent the past few weeks experimenting. I have heard all of the fancy explanations over the years from different cord manufacturers and salesmen about the mystical properties of their cord vs. the others, and the majority of it is probably hogwash. On the other hand, just maximizing the current flow by using low gauge wire like objectivist engineers say, while the main function of the wire, and very important especially for high current amps, isn't the only answer. I believe the major effect on AC improvement is in designing the wire to reject both the noise coming through the AC line, and the RF picked up by the wire itself acting as a receiving antenna, and the noise it can inject into the room as a transmitting antenna from the digital equipment.
There has also been a marked improvement in AC cords over the years, both in their ability to bring purer current to the equipment and the price relative to the value they perform. Cords costing as little as $300 now do the job of those costing $1,200 just three years ago. During my experimentation I pulled out my old Distech cables from 10 years ago and compared them with the three-year-old Electraglides and the new cords discussed below. There have been marked improvements in the ability to get rid of AC line noise. So while there still is not much published science on the whereas and
whyfors, some of the high end experimenters out there certainly have found techniques that work for AC filtering, while not degrading the current passing capability of the cord.
The properties I feel are important for audio AC cords are:
1.Use of high purity copper or silver drawn and slowly cooled so as to decrease the number of discontinuities of the crystal lattice the electrons have to jump over. Adding deep freeze cryo to the wire in liquid nitrogen also seems to decrease some sort of grunge that wires either produce or transmit.
2.Appropriate insulation with a low dielectric constant to decrease smearing of the AC sine wave. Preferably with air if/when possible.
3.Flat thin wires running in parallel seem to work much better at decreasing RF transmission. Unhappily it is quite difficult to produce high current wires using properties 2 and 3. Thus:
4. High current cords should be made of multiple strands of high gauge copper or silver for easy bend ability, tightly interweaved in such a way as to decrease capacitance and inductance or mold the capacitance and inductance such that the wire can act as a band pass crossover maximizing the 60Hz pass band and minimizing the noise at other frequencies.
5.Shielding using either copper or aluminum tied off to AC ground will increase the RF rejection antenna effect and decrease noise generated by the cable into the room. But there must be a dielectric spacing between the shield and wire such that the shield doesn't interfere with the signal, preferably air.
6. Even better seems to be adding a DC voltage to the shield to take the shield above ground potential. Why this works I don't know, but I can certainly hear a difference when the potential is removed from the wires that use it.
7. The plugs should be made of heavy gauge pure copper, well constructed so that they fit tightly to the wall plug. Cryo seems to help them also. Also adding a contact enhancer, such as Caig Pro-Gold maximizes electron transfer and prevents oxidation of the surfaces.
8. There is a polarity to AC cords dependent on a piece of equipment. That may be why cords will sound different in different systems with similar equipment. I did not believe this until last week, as it is hard to demonstrate with compared to interconnect and loudspeaker cables as the ends are different and thus a cord is not reversible. I will discuss this further below.
For the past two weeks I have been playing around with the various power cords mentioned below, trading them in and out of the system in various positions with various pieces of equipment, reversing the wall polarity and lifting the ground using cheater plugs, only doing this in the afternoon and early evening when my electricity seems to be the noisiest. The cords evaluated and where I found them to have best use were:
1. Electraglide Reference Glide ($799), Fatboy Silver (originally
$1,299). While they were top of the line cables several years ago, they have lost out compared to those below, and I have relegated them to use on some of my video equipment and the surround channels. I would say they are pretty equivalent in line noise reduction to #3. Below at a higher cost. They are also practically unbendable and thick, but they are very light. I have not heard their latest cable so I am unsure if they have kept up quality wise. I still use them in ancillary equipment, such as the printer connected to my
2. Elrod EPS-3 Signature Cables, $1,600. These are superb high current cables using foil wiring with proprietary insulation and shielding reviewed in AA Chapter 45. They are wonderful for amplifiers or as a mains cable between the wall and line conditioners. While expensive, they are the best cords I have found for amplifiers price no object, but are heavy and very stiff. I am using two of these on my woofer power amps and boy do they add control to the bottom end. If they were less expensive, I'd be using them or his EPS-2 low current cables on everything.
DH Labs Power Plus AC Cables
3. DH Labs Power Plus AC
Cables. These are made of 12-gauge high purity copper interleaved in such a way as to minimize inductance and capacitance while attempting to decrease electric fields produced around the cable that may affect the equipment they are attached to. This has got to be the best bargain of all the cables tested at $6 per foot for bulk cable and $200 for a 2 meter terminated cable they are the least expensive cables I've heard that can be considered high end. They are very malleable, about 1/2 inch in diameter and come with excellent plugs. The bulk cord is a super deal, and if I hadn't wired from the junction box to my room already, I would get a run to use inside of some flexible shielding to bring it up to electrical code. The surface is very slippery, and it is designed to have a low electrical field, so it may be the ideal cable for long runs in the room walls. While not quite as noise free as 4. Below, you can't beat the price for value. I'll be buying several to use with my video equipment to replace the Electraglide stuff at a significant cost saving.
Silent Source AC Cables
4. Silent Source AC Cables as discussed in AA Chapter 45. In the low cost area, these cables stand out as the best I've used, almost coming up to the most expensive in AC noise reduction. In addition, his top of the line cable is built for 50A transmission, yet are very flexible and visually attractive. The plugs are of the best quality. At $580 for 6 feet and $70 per foot extra, they are a steal for what they do, which is give inky black background to the sound with lightening fast transients. They are almost as good as 5 below, just missing in absolute noise reduction. If you can afford the added price compared to the DH Labs cable, they can also be made up in up to 30 foot lengths for long room runs. They don't have a web site yet but both these and 5. Can be purchased from my old nemesis, Lloyd Walker of
I was so enamored with the price to sound ratio of the Silent Source power cords, that I called Frank Dickens, the owner and developer and asked him if I could purchase some specially made runs from my 50A feeds to the Sound Application units. Thus replacing the 12- and 30-foot runs of Romex I had been using and 2-meter runs from the
CF-XE to each Walker Velocitor unit. He happily obliged, making the long runs out of his 50A cryo treated cable, leaving the proximal ends bare so I could hot wire directly to the circuit breakers (thus eliminating a set of plugs) and with a 20A female IEC plug at the other end to connect with the
CF-XE units. That dropped out the noise I was getting from the surround loudspeakers to an amazing degree. Silence is Golden when it comes to AC interference. The back of the room opened up given a homogeneous sound field compared to the separate speaker sound I was getting previously. And that is what great AC conditioning does primarily -- opens up the sound stage into a whole field.
Omega Micro Planar III AC Cables
5. Omega Micro Planar III AC Cables. These have been around for several years, and Lloyd Walker of
Walker Audio had suggested several times that I try them. I had heard their speaker cables several years ago at The Listening Studio, and while they sounded great, they looked very tweaky, which, believe it or not, was a turnoff for me for some reason. Lloyd finally talked me into trying a few of them, and like the rest of his temptations (his phone number begins with 666, you figure it out) as usual; he gave me a free return guarantee if I didn't like them. Developed originally by Ron Bauman of Insound and Piere Sprey of Mapleshade Recording, who, by the way, makes superb digital primarily jazz recordings. The cables are interestingly, constructed using most of the parameters I have found to be important in AC cords.
First, they look beautiful and are very malleable, thus easy on the eye and to bend around corners. They use a braided copper shield that is silver coated which gives the beauty, but the shield is not insulated and for best effect should not touch anything such as carpeting or anything conductive. Why? Because the shield in the LCX series is raised above ground potential by using two 9 Volt batteries in a wooden case that are tied between the shield and the cable ground. Since the connection has only one side, there is no circuit. Therefore the batteries never wear down except from age. They are only there to give a DC potential to the shield. I do not know why this works, but there is a significant difference in equipment sound if the DC potential is lost.
Second, they use flat thin ribbon of high purity, the composition of which I cannot ascertain. Because of the thinness, they only recommend running a maximum of 900 watts through them, which is great for low source equipment and low wattage amplifiers but a No-No for large amplifiers and signal conditioners. Third, they have primarily an air dielectric. Fourth, the plugs, while flimsy looking have somewhat thicker than normal prongs, which make for a tight fit.
Fifth, and possibly most important, they have two cables that they label blue and red (with the same build) except for a reversal of the polarity of the ribbon. They have found, like their loudspeaker wire and interconnect, that the signal transmission (AC here) is dependent on how the wire reacts with the AC transformer of the equipment. Thus, they always send a pair with one wire of each type so that the individual can experiment with wire polarity on each piece of equipment.
The wire polarity seems to be somewhat more important than the shield potential. One can tell immediately when the proper polarity wire is in place, as the soundstage opens up. I even had my wife come in and change the wire polarity
type, and I heard the difference 100% of the time. One can also hear a moderate improvement in soundstage with the shield potential activated, but it is not of the same extent as the wire polarity. Interestingly they claim that about 66% of American equipment prefers the red to blue type, but I found it about 50-50.
With the proper polarity and with the electric field activated, the wire has no sound. On each piece of low wattage equipment I have tried it on, it has dropped the background noise level compared to all other wires. Its greatest effect has been on digital equipment where it wipes out digital high frequency anomalies and (especially with SACD and DVD-A) opens up the soundstage, probably by allowing very low volume hall sounds to be heard. It made a tremendous difference on my EAD Theatermaster Signature Pre-Pro, especially with Dolby Digital and DTS DVD-V's where there is less information to begin with. I now have it for my Denon 2900 combi player, the EAD
Theatermaster, both of my pre-amplifiers and my two Electraprint DRD SET 300B amplifiers. Each Omega wire added has improved the sound.
I am planning on buying several more for the rest of my low wattage equipment, but just cannot afford to do the entire system. Each 5 foot passive cable costs $485 and the active shield LCX version costs $955. While expensive, especially compared to the price of most digital equipment, the LCX can not be beat. Is the active shield worth double the cost? Considering the cost of two 9-Watt batteries, the small wooden box and the two fine wires that lead into the cable, the added expense is high yet well worth it. You get what you pay for, and in high-end audio quite often not. But the Omega Micro LCX
is definitely worth the admission price.
So why am I done reviewing AC cables. Because I have found the ideal combination for my system with the Silent Source, Elrod DH Labs and Omega's in their appropriate places. While I am willing to do some further experimentation with AC, I am satisfied with what I've got, which is the first time
I have been able to say that in 22 years.
Next month I will be back to analog. I have hooked a Loricraft record-cleaning machine and I can not wait to try it.