Review: PURE NOTE SIGMA Power cord

Category: Cables

I have held off on purchasing aftermarket power cords of several reasons. First of all in my system, I will be looking at six power cords, if I am to replace all of the factory cords. As many of the cords that have gotten good reviews are priced at a thousand or more, the price for new cables could become prohibitive. Second, replacing power cords made no sense. Since the current has already traveled about 50 feet thru the Romex of my dedicated lines, why would the last 3 feet change things? And lastly, Krell discourages the use of aftermarket cords saying they do not help with their equipment...and I have Krell gear.

That said, about six months ago I started researching the various brands and types of power cords. There were about as many opinions as types of cords.

One brand of power cord really sparked my interest. It was mid-priced ($200/3ft) and I heard no one that said they had compared and found one better, at any price. In fact, that same company use to make a cord for $900 that they discontinued because the less expensive cord sounded better. That cord is the PURE NOTE SIGMA.

Before I describe my experiences to date, let me briefly describe my system. I have B&W800's actively bi-amped via the Krell KBX, with the changes to the B&W crossover designed by Dan D'Agostino of Krell. The mid/highs are driven by the Krell FPB300 and the bass section driven by the Krell KSA300S. Preamp is the Krell KRC-HR and the source is the Krell Studio driven via AT&T by the EAD T-7000. The system is balanced from start to finish.

When I received my first PURE NOTE power cord, I hooked it up to my preamp for about four days to let it burn in. Then I began serious listening. I was not surprised to find no change compared to the stock cord. I then tried the cord on my D to A. Again, no change. I figured that I was correct and that all the hype was just that, hype. I then had to go out of town for a week. After returning, I decided to give the PURE NOTE another try. It had been plugged into the preamp all this time. Comparing this time, things were totally different. Every time I went back to the stock cord and then back to the PURE NOTE, it was obvious that the PURE NOTE was better, much better. Clearer sharper highs, fuller midrange, and a more exciting sound. It has been powering my KRC-HR ever since.

Then, it was time to see what their power cord would do for my FPB300 which drives the mid/highs of the B&W800's. Since it requires the 20 amp IEC connector, I had to order another cable. When It came, I immediately hooked it up to the amp and let it burn in for 5 days. When I sat down to compare it to the stock cable, there was again no difference. I was not surprised as Krell says the FPB series is immune to current variations and now even supplies the FPB with a non-removable cord. I contacted PURE NOTE and suggested that I return it, but they said keep it another week. Well, the same thing happened as happened with the preamp. Now with 12 days of burning in, the change was again dramatic. The sound again became airier and more exciting. No doubt about it, this is some fabulous power cord. The improvements are not subtle. It too, has been powering my FPB300 ever since.

This is a review in progress. Next, I will be experimenting placing the PURE NOTE SIGMA on the bass amp and the electronic crossover, followed by the digital units. I hope to write more in the future. Please keep watching.

WARNING: Give the cord at least 10 days to burn in at home before evaluating it.
Hello Drrdiamond, are you trying to tease us? Or this is some kind of trolling. :-) True, we know that there is no scientifics explanation for PCs and ICs. But they work! Just "spend with senseā€! Nice setup you've gotten there by the way.

ISTT: With all the hoopla of late about Bob Crump's power cords what is the issue here? I own the Pure Note Sigma power cords and I agree with the Doc's findings. These are great power cords for the money (if you believe power cords really matter).
An info follow up:

These great cords can be seen at:

I recently had the privilege of demoing a Pure Note Sigma power cord. I found it to be a very good power cord for the dollar spent, and could compete with power cords costing twice of the cost of the Sigma.