The last 6 feet - is it important?

The question I've see many times on several forums is....

When you have 50 ft of Romex from the breaker panel to the outlet, why is the last 6ft of power cable important?

So I started looking at how some of the better performing power cables are constructed and one thing stood out - many of them had lots of individually insulated wires for each conductor.

When you construct something in that manner it normally increases the capacitance.

We know excessive capacitance is not the best thing to have in an Interconnect and in some cases in speaker cables because of the "stored energy"

But if a power cable could "store energy" then it would improve it's ability to satisfy transient demands.

So knowing Kimber cable uses multi strand conductors for their speaker cables resulting in a higher capacitance than many other brands - I decided to build a power cable out of Kimber 4PR.

The 4PR was used for the live and neutral conductors (approximately 10 gauge) and a plain old piece of multi strand copper wire was used for ground.

Each conductor had shrink sleeve added to compress the strands and add extra insulation and finished off with nylon cable sleeve. I braided the conductors to aid with RF rejection. Total cost with connectors $100 for a 5ft cable

I installed the cable on my DAC which had a Furutech FP-3TS762 20 amp 10 gauge cable with silver plated copper connectors.

It took about 5 minutes to appreciate the improvement - even before being burned in...
- vast improvement in image - deeper and wider
- much improved clarity
- much improved details
- much improved dynamics

Now I don't know for sure whether it's "Stored Energy" due to capacitance that's making the difference here. But the quality of the copper in both cables is very similar, the gauge is practically identical and the quality of the connectors are also very similar.

All I know is what I am hearing is much nicer than with the Furutech cable.

Now before you start slamming the Furutech cable - the DAC is plugged into a DIY power distribution box and the cable connecting that to the outlet is the very same Furutech 10 gauge cable.

Now I've see some manufacturer of power cables mention that they recommend a minimum of 5-6ft of cable be used for best results - increasing the length would increase the cable's capacitance, improving it's ability to store energy and provide better performance. Or is it just to get you to spend more

SO - does anyone else have an alternate theory as to why the last six feet is important?

Would like to hear an explanation :-)
UPDATE - Ive since constructed a second cable from Kimber 4TC - a better quality cable.

Their was a discernable improvement in micro-details, dynamics and a slightlly deeper image. The difference in price was an additional $60 for a five foot cable.

Was it worth it? - if the component you intend to use it on is capable of higher resolution - the it definately is :-)

But the cable made from Kimber 4PR is a very capable performer.

Willie ... I've posted this Q on another thread, but I'll ask you here. I use Kimber 8PR speaker cables. Seems like you think there IS a difference between the PR and TC series. Correct?? Just a tad curious why that is so given the cables specs re impedance, capacitance and inductance look almost identical. Any thoughts?? Thanks.
Bifwynne - it's the quality of the copper used in the TC range - "hyper pure copper"- it probably has higher IACS conductivity rating, but they don't publish that.

I've found that all cables with higher quality copper - or better still silver -have better dynamics and bass response - but you then need quality connectors like Furez otherwise the improvements are reduced significantly

Hope that makes sense

Wille ... what is IACS conductivity? Sorry if that's a dumb question.
Bif - no such thing as a dumb question.

International Annealed Copper Standard:
It’s a measure of the conductivity of various metals relative to “Pure Copper” having a rating of 100%, a standard developed for copper wire producers.

For Complete Definition See:
IACC Definition

For values of different metals/alloys see:
IACC Table

What I have discovered over the last little while is that conductors (i.e. wires and connectors) with higher IACS rating tend to be more dynamic in their presentation.

The TC line of Kimber cables allow for noticeably faster dynamics with more detail.

However - if high value conductors, like the 4TC, is used with with lower valued Brass Bananas or spades you are definitely not getting the most out of the cables.

If you think about it - the electrons flying down the high purity copper highway and hitting a brass toll booth :-)

I have Silver interconnect cables rated round 106% with copper alloy RCA's rated around 80%. They sounded pretty nice and quite detailed, but not what I would call smoooooth.

Upgrading the RCA's to a solid silver RCA made a very big difference and improved clarity and dynamics with a definite mellowing of the high frequencies - without loosing details.

I also applied a similar upgrade to my speaker cables, which were already silver coated high purity copper. Adding silver coated high conductive copper FUREZ Bananas improved overall clarity and dynamics.

Hope this clarifies things :-)

Why get your head in a tizzy with fantasy theories.
Take an aftermarket powercable and try it.
For some of us it works better.
Case closed. No need to remake all of science to enjoy.

If you find it impossible to enjoy withouth some cosmic theory.. Sorry I can't help you.
Very interesting Willie. Thanks.

Notably, the IACS rating of alloys, even copper alloys, "goes south" pretty quickly. But the various grades of "pure" copper were still very high.

I buy your point that interposing an alloy interconnector, or as some have also said, speaker terminal jumpers, can affect sonics. Especially after having looked at the IACS chart.

Still not drinking the Kool-Aid on the various grades of speaker cabling made of pure, versus hyper, versus ultra pure copper. But I may have a different view after trying out the better grades. If so, I'll be back.

Thanks again.
Bif - it's Gatorade - it enhances performance !

Couldnt resist :-)
I read an interesting article about the last few feet of power cord are the first few feet your system sees.
A simple analogy that helps me in understanding why a good PC could help is the purpose of a water filter on your faucet at home. After miles of pipe from the water treatment plant then through all your homes plumbing how in the world could a little water filter at your faucet improve anything about that water?

All I'm sure of is that the water tastes better after its been through that filter just as I'm sure my system sounds better with my after market PC. Of course none of this explains why I just know from my experience it does. It would kill me to go back to my stock power card for my amp.

I think I read the water filter analogy in a Michael Fremer article in S'Phile.
Forget about all you hear about all those miles, towers and transformers your power must overcome before it arrives at your outlet. What is measured at the outlet is what your system sees.

All the best,
I've used some high end fuses in place of the standard Radio Shack type. They also make a noticeable improvement in sound quality and goes hand in hand with upgraded power cables.
The water filter analogy works for power filters and conditioners and re-generators, but seems weak at best for power cords. Unless those cords filter the power intentionally or otherwise.
I uderstand that the filter analogy might help lower the noise floor and bring
the details out - but how does it help with dynamics ?

You really need instantaneous power "reserves" to improve
dynamics don't you?

Simply putting in good copper didn't bring the dynamics to the level I'm
now experiencing. And using a silver alloy power cable didn't do the trick

One last thing - the 6.5 ft cable is more dynamic than the 5ft cable - could
it be it stores even more energy?

Any other theories :-)
Drubin, yes the PC I use is one that is considered a power conditioning cord.

Williewonka, I'm not surprised you find the 6.5ft cable more dynamic. The manufacture of my PC recommends a minimum of 6ft for best performance.
Samac - do they specify a max length ?

What brand/mpdel are you using?

Williiewonka, I'm using a WireWorld Stratus PC. A max length is not specified. A came across the six foot minimum spec from a review I read and talking with WireWorld.
Samac - that is a very interesting power cord design - I will be looking into those for sure

Like the look of their Silver Electra 7's

"Like the look of their Silver Electra 7's"

Yes, me too. The Silver Electra is out of my budget though. Eventually I'm going to put the Stratus on my iMac and get an Electra for my amp.

Over the past couple of months I have replaced all my cabling and now have a complete suite of WireWorld in my system. They (WireWorld) seem to be doing something very right in their combination of materials, geometry and shielding. For the first time in ten years I am listening to music and not my system.

Now, that could mean I'm just not good at this hifi game but I believe it has to do with how good the WireWorld cables are.:-)
Samac - You remind me of me :-)

Never realised how much difference power cables actually made - then voila!

It really is an epipheny isn't it !

I've wanted to try upgraded power cords but for years I had captive power cords on my equipment. With the integrated I have now I was able to try different cords.

I put a 14g shielded Belden on and it was such a profound improvement a couple of weeks later a added the Stratus.

Yes, it was an exciting discovery.:-) Makes me wonder why manufactures don't offer or suggest upgraded power cords more often. It makes such a difference. I believe Rega recently started offering one.

If you try a WW PC please keep me posted. I wont be swapping any PCs and I'd like to get your take on comparisons. Thanks.


UPDATE: Since making the 4TC power cord mentioned above, I have been
looking at some other designs on the market and those which appear to
work very well use a braided design.

I had tried Braided romex in the past and it worked quite well, but it was
very stiff, so I figured I'd try a more flexible cable.

I went to Lowe's (the hardware store) and purchased a 25ft 12 gauge
extension cord - nothing fancy - cost $35. I then cut off about 6 ft and
striped the outer sheathing from the cable to leave me with the three

Using a simple braiding technique I make up the power cable and attached
some crimped spades and some fairly affordable IEC/mains connectors
($20 for the two)

Total Cost for a 5-6 ft cable about $35

What happened next left me gob-smacked - it performed almost as well as
the 4TC braided power cable - which is made from superior copper and has
much better connectors.

Since the Furutech power cable I have has very good quality copper
conductors I performed the same process - removing the sheathing and
shielding - leaving me with the three conductors. Again I applied the
crimped spade and IEC connectors to the braided cable.

The result was again quite astonishing - it performed better than the more
expensive Kimber 4TC power cable, with better control across the board
and a deeper image.

So if you are thinking of upgrading your power cords but don't want to
spend megabucks - try the inexpensive braided version made from a 12
gauge power cable - it really is very good

If you want something between the cheapie and the Furutech, then try the
Power Plus power cable from DH Labs and braid as above. It shou.d
perform very close to the Furutech for about 1/3 the cost