August 2006

Audiolics Anonymous Chapter 82
Electricity Again... APC S15 Power Conditioner
Article By Bill Gaw

  Welcome to another gathering of our therapy group for the audio insane. Over the past 25 years, I’ve probably spent more than the lifetime incomes of 95 percent of the world’s population on my stereo system to get it as close as possible to the so-called “Absolute Sound” of live unamplified direct to the ears from the performer, music. Several times along the way, a point has been reached where it appeared that close to the ultimate had been obtained, usually during some listening session late at night when the system sounds superb, only to turn it on the next day, and find that the illusion was only a delusion, as the sound had lost some of its beauty.

As I’ve aged, the need to improve on the system has also diminished. It’s probable that as we get older, we tend to allow ourselves to regress to the mean, meaning that we don’t feel the necessity to go the extra step.

We also come to a point where our systems start sounding so good, and we become so adjusted to their sound that we feel that no further improvements are needed or can be accomplished. The sound is so superb that we fool ourselves into thinking that nothing more can be improved and that our ultimate enjoyment has been reached.

For instance, a couple of months ago I reviewed the THOR Power Distribution System, (AA Chapter 78) and declared that it had completely eradicated any and all gremlins that the electric company was delivering to my system. Satisfied, that the electricity had been scrubbed of all nasties, I felt that no further improvement could be made on this side. Today’s review product has taught me that this is probably never so. Except for running on multiple battery power supplies producing pure direct current, there is always some sort of junk entering your systems through your electric line that distorts the audio signal, and each component in the system adds its own gremlins, especially digital.

As most of my regular readers know by now, my pet peeve for years has been the crappy electricity that most of us are saddled with. While most of our equipment would be very happy if it could receive a pure DC current, due to decisions made back in the beginning of the 20^th century, AC became the standard. Unhappily Direct current even at high voltages does not flow as easily through wire and thus the amount transmitted rapidly drops off in the transmission lines. Equally important, it is very difficult to change the voltage of direct current so all appliances would have to use the same voltage delivered to the house.

On the other hand if the electricity is transmitted to our houses as alternating current,  it can be sent at very high voltages which can then be stepped down to lower voltages by transformers along the transmission lines, which then needs to be changed by a transformer near your house to the standard 110 to 250 Volts, 50 to 60 Hz. Also, electric lines, whether they were carrying direct or alternating current, are still prone to act as massive antennas picking up all sorts of interference from the environment, both natural and man-made.

Then, in audio and video equipment, which can require anything from 5 volts to run transistors to 750 Volts for the biggest tubes, the house voltage must be changed, and in some equipment, several different voltages are required.  Finally, most of the equipment will require that the AC current be rectified to as pure a direct current as possible.

There are four flies in the ointment here:

First, unhappily there is no such thing as a pure 60 Hz. current arriving at your house. We’ve discussed this in several articles in the past (AA Chapter 3, 15,25, 30,35, 4462,75,76, 78, see archives by clicking here) so all that need to be said is that the electricity received in the average house could be equivalent to your drinking water being supplied from your sewer pipe. The average AC wave looks like the Atlantic Ocean in hurricane season rather than a pure sine wave. That’s probably an exaggeration, but not by much, and its getting worse year by year. There is actually a system now for transmission of all the digital data in your house through the electrical system, which ought to add further to the problem.

Second, there is no reasonably priced piece of rectification equipment that will create perfect straight-line direct current. Old-fashioned tube rectification with inductors came close, but modern solid-state rectification with less expensive capacitor rectification not only leaves some ripple in the DC, meaning alternating current, but also sometimes adds so-called switching noise to the DC. Several stages of rectification will normally decrease the amount of AC riding on the DC, but each stage wastes power as heat, decreases the voltage available, and adds significant cost to the equipment. Any AC ripple will show up as distortion at the speakers.

Third, in order for the equipment to get the correct direct current amperage, the rectifier must react to the top and bottom of the sine wave, which may be difficult to do if there is no sine wave to begin with. In addition, in most cases, the voltage wave is not perfectly aligned with the current wave (don’t look at me, I don’t understand this either!!), which also screws up the ability of the power supply to get the correct voltage and amperage for the individual circuits.

Finally, all digital circuitry produces noise in each piece of equipment, which must be filtered out from the electricity passing to the next stage or piece of equipment. Filters at equipment outputs are usually capacitors which only filter out DC, so the AC ripple,( read noise,)  from the power supplies is amplified with the signal and passed on to the next stage in each piece of equipment. So unless each stage has optimal isolation from its power supply any noise from the power lines will be amplified. In most audio equipment, there is a direct flow of electricity from the output of the power supply to the output signal, with all of the circuitry just adding audio or video in the form of varying alternating current with the direct current carrier being filtered out between circuits or equipment. Thus any electrical gremlins that the power supply or output filters allow through rides on the music and distorts it.

Over the years, I’ve tried and reviewed multiple different equipment made for improving the electricity arriving at the inputs of my equipment, everything from multiple high amperage transformers with large capacitors, to power cords too expensive for the military to buy, to AC-DC-AC inverters, converters, etc., to a complete redo of my house’s electrical system. Some have helped but most were a waste of money either because they didn’t work or they did something to the electricity that actually in some way negatively affected the sound.

Until now, the following changes have improved on the electricity reaching my system and are highly recommended:

1. Call your electrical company and have them evaluate their system from their high voltage transformer in your area back to the house transformer. My company found some sort of switch at the high voltage transformer that wasn’t functioning properly, which they replaced,  and that my house transformer was being overtaxed by the number of houses attached to it. If you can get your own house transformer, go for it, although the electrical company will be reluctant to do this. Cuts down tremendously on noise from your neighbor’s houses. No charge.

2. Make sure your junction box and service is up to date. At least 200 amps would be good, 400 better if you have central air conditioning or heat. Also make sure all connections are not corroded, especially the ground both at the junction box and outside the house. Put in the best grounding rod possible, preferably copper, or if you have a well, run a thick copper wire to its grounding plug. $500 to $1500.

3. Run at least a 20 and preferably a higher amperage dedicated line to your listening room. My dedicated line is a 60-Ampre sub box with four 20 Ampere fuses. $500

4. Try grounding all equipment at one central star ground for least hum. No chrage.

5. Put in sufficient surge protection at the junction box. The best I’ve found is an industrial model; the Environmental Potentials EP-2050, which also does an excellent job at getting rid of some of the high frequency noise on the line. $700 plus electrician or do it yourself.

6. Invest in some good to very good power cords for at least the most important components. This can cost anywhere from $80 to $2000 per cord so I won’t estimate the cost for you. This recommendation may change by the end of this article.

7. Treat all connections including the wall outlets with Walker Audio Extreme Super Silver Treatment to decrease junction noise and increase current flow. Well worth the $150.

8. Invest in a Thor Power Distribution System sold in the USA by Nordost. Until this article, this unit was the second biggest improvement to the electricity that my system has had, the best and most important being the dedicated power line. While it’s not cheap at $3200 it’s well worth the price, at least until today’s review piece.

So what’s this long introduction leading up to? The best piece of equipment for reducing electrical noise that’s entered my system (and to boot, reasonably priced) is from a non-high-end company.

Remember, a couple of months ago, I was completely satisfied with the sound coming from my system, and had thought that all of the electrical gremlins had been defeated. Gone was the difference in listening between 6 PM and midnight. The system sounded great any time of day, with considerably less noise, and even what was taken for tube hiss had decreased considerably to the point where, even with my 106dB per watt sensitive horn speakers, one had to come very close to the horn to hear any noise. The loudest sound in the room when music wasn’t playing from the seven horns and seven subwoofers was the fan on the Crown Macro Reference amplifier, which was hidden behind the front center speaker surrounded by Sonex. I was a happy camper for the first time in years.

Then I heard about a new product from a non-audio related company called American Power Conversion Corporation, maker for 20 years of power protection equipment for everything from home computers to large government installations. If you’ve had a computer in your house, it’s almost a surety you’ve had one of their uninterruptible power supplies protecting it.

Not satisfied with being one of the largest companies of this type, they decided to form a branch to produce protection equipment designed especially for audio-video systems. From the looks of it, they have combined the knowledge obtained from their computer UPS products with some excellent research into how home audio-video systems are set up, and came up with their

APC S10 & S15 Power Conditioner With Battery Backup
They realized that audio systems are very prone to signal degradation from less than pure 60 Hz. sine waves, so instead of producing the typical power supply with a square wave or so-called modified sine wave full of harmonics, they did the right thing and produced a pure 60 Hz. sine wave. Then they took the twelve outlets and separated them into five separate isolated banks, consisting of 6 for digital equipment, two for video, two for low power equipment, and two for high powered amplifiers, these latter two having different protection to minimize affecting current draw with high volume surges. Two of the sections were placed on delayed turn-on so that preamps and other source equipment will be fully powered up before the amplifiers so major thumps causing speaker damage won’t occur.

For those fanatics who can hear fan noise, they set up the fan in their unit only to go on when the unit is on battery back-up or in an over-wattage situation. While this is great 99 percent of the time, one of its three minor faults by my standards is that when the fan does come on it is fairly loud. Thus if you want to go off the electrical line you should place the unit somewhere out of noise range. Happily this only occurs on sound peaks, which will mask the noise somewhat.

Then they built in some battery backup to help further the isolation from the mains, smooth power requirements when sudden surges call for extra power and to give some shut-down time for the system if the AC is suddenly removed by power loss so that the amps are not still on when the preamps shut down. For those fanatics who want to completely isolate themselves from the power grid, they added an inlet for daisy-chained battery backup units to give as much off the grid time as required.

To completely isolate the system from over voltage and lightning strikes, they supplied three sets of F plugs for TV cables, Ethernet and phone ports. Surges from all inputs are limited to a maximum of less than 40 volts with a 6000-Volt strike, far below the standard for other units.

The back of the unit also has a light showing faulty grounding. It came on when I used one of my high end power cords, which made me realize that I had cut off the grounding pin previously because the equipment it was being used on gave a 60 Hz. hum. Obviously the unit wants the ground to be there to shunt noise away from the system.

They supply an excellent 12 gauge AC cord and have an IEC plug for those high-enders wishing to use specialty cords. During my trials, there was no difference in sound between their AC cable and several high-end cables tried. Save your money.

The front of the unit is a separate panel that snaps into place and has all of the controls and an LCD screen. While the vacuum fluorescent display (VFD) is very bright, they can be turned off so that they don’t interfere with late night listening or viewing. Unhappily, minor fault # 2 is that a bright blue ring light around the on-off button stays on, which is somewhat distracting. It should cut off with the other lights. Put some black tape over it.

So What Does The Unit Do?
First, it corrects for voltage changes, and actually shows the in and output voltages on the VFD.  The unit will keep 118 to 122 Volts between 90 to 135 Volts and suppress surges when the power turns off and comes back on. While we have the poorest power line noise in my area, far surpassing New York’s according to fellow audiophiles who’ve visited here, the voltage in my area is fairly stable with minimal brown-outs.  We did have a couple of quick power drops at which times the house lights dimmed for several seconds, the unit recorded an average input of 105 Volts, with an output of a steady 118 volts. The only difference with the unit was that the fan turned on and the unit made up for the lowered voltage by adding juice from the batteries, rather than the use of a variable transformer like many other units. It did this very quickly as even the home theater computer that was attached to the unit didn’t stutter.

Second, it prevents voltage surges not only through the AC, but also from external antennas, cable TV hookups, telephone and Ethernet connections to external computers. A couple of years ago, we had a surge through my C-band satellite dish due to a lightning strike a mile away from the house, that came in through the antenna cable which wiped out a VCR and the satellite receiver. APC guarantees against this problem.

Third, it supplies 900 watts average of clean power. And i do mean clean!!! If you’ve read my previous articles, you know that my system is already very isolated from AC noise, using the THOR unit from Nordost, two Environmental Potentials 2450 units at the system and their 2050 wave correction unit at my junction box, and high end audio cables and Walker Audio Velocitors on all equipment, so the system should have optimal isolation from the worst the power company can dish out.

Well this unit surpasses all of them when used alone and actually cleans up the power further when used in addition to the above. I wouldn’t have believed it as the system was sounding superb before. Adding the APC decreased noise coming from the speakers further to the point of inaudibility of any extraneous sound. This allows more ambient and very low-level information to come through which adds to the realism of the presentation. In addition, bass became tighter and more lifelike, less boomy and chestier. High frequency hash disappeared. On surround there was a more life-like presentation of three-dimensional space.

Clark Johnsen was over last night and brought a 5.1 channel SACD recording from Ray Kimber using his ISOMIKE system, and on one of the bands Ray has singers in a circle around the mikes saying their names. This is the first time when I actually could hear a true image of a person coming from between the front and side speakers; something some audio experts say cannot be done. On two channel recordings, one can perceive a definite concert hall space out to beyond the listener on great recordings, something I’ve only heard rarely late at night. That’s life-like reproduction of space. Used alone, without any of the other pieces of equipment but with the high-end cords, the unit does as well as all of the other pieces of equipment combined at improving the sound, and this without any of the adverse effects heard previously with other line cleaners.

For the average audio video system one unit will be adequate, but for some high enders with mega-watt amplifiers, or others, such as me, with a 7.1 channel system with seven subwoofers and a 9-inch CRT projector, one unit may not be enough. Happily, the unit reads out the wattage used and when it goes over about 920 watts will beep, turn on its lights and add battery backup, allowing surges up to about 1800 watts before pooping out. Unhappily it keeps making both beeping and fan noise after a few seconds, so it shouldn’t be used in over wattage situations for long periods of time. The company has assured me that any short-term over wattage situations will not harm the unit. I guarantee you that if you have a big subwoofer and watch action movies, over wattage will occur. For my situation, the company sent me a second unit, and using the wattage meters, and the fact most of my amps are Class A tubes requiring a continuous wattage, I was able to almost balance perfectly my system such that one unit was using an average of 768 and the other 802 watts. As one subwoofer amp was attached to each unit, even on Star Wars III, both peaked out in short bursts at about 1600 watts without ill effects, except for the listeners, some of whom had damp pants.

I hope this will be my last column on electricity as this unit alone has improved my system to the point where I could live with it forever, and with the addition of the THOR and my various high end power cords, seems to have solved all of my AC problems.  Whether it will do the same for you and whether its worth its $1499 list price to you really depends on how polluted your AC is and how much of an audio fanatic you are. This unit is the best AC cleaner that I’ve encountered and both will be staying in my system. If it had been available three months ago, the THOR wouldn’t have been purchased, and if 10 years ago my bank account would be significantly stronger today.

For those with smaller systems, the S-10 may be sufficient as it is built to the same standards, just with a lower wattage rating.

I give it my highest recommendation.