[avahifi]

I have received and tested to the best of my ability the high grade power cord Occam so generously sent me to evaluate.

I compared it to the standard 16 gauge 2 conductor polarized power cords we supply on all our equipment. Ours cost about $2.00 each.

My first test with with my signal generator and dual trace scope, looking for any (desirable) high frequency roll-off differences between the cables.  If the cable better filtered out high frequency garbage on the power line, that would be a bonus. I was unable to load the cables into a typical low impedance dummy load, simulating the output load the cable would see - -  the input impedance of the power transformer, because my generator won't drive such a low impedance load.  So the measurements were made into an open, looking at the signal both at the input and output ends of the cables.  The result, up to the 3 meg capability of my generator and scope, there were no differences between the stock cable and Occam's cable.  This, I think, shows that the cables are not providing any high frequency trash filtering at all.  Input and output was essentially the same with both cables.  My power cord measured about 0.2 ohms resistance, Occam's near zero with my Fluke meter.

I then replaced the stock power cord with Occam's in a new production Insight DAC.  I bench tested it again and saw no differences in the performance we can measure (as expected).  We can't measure many of the engineering changes we make here under rather inexact test capabilities either.

For listening tests, I set up two identical Insight DACs, one with a stock power cord, one with Occam's power cord.  I then set up a double blind ABX test using our best preamp and amplifier and Salk HT3 speakers in my sound room on material I am very familiar with.

Both DACs were stacked, both on, and either one or the other was connected to the transport and preamp.  I first listened to one for a CD cut and then the other, knowing which I was listening to and could tell no significant difference.

Then we ran a five test blind evaluation.  My assistant was told to connect one of the DACs making sure I could not tell which was connected.  The music was then started and I listened.  After each test my assistant was told to either change DACs or not change DACs as he felt like it, except for the last test he was told to definitely change DACs, but never would I know from what to what. I made notes as follows after each of five tests.

1.  Don't know  --- maybe stock DAC.

2.  Maybe with Occam's cable.

3.  No change from #2

4.  Maybe stock

5.  Really can't hear any change. Can't tell.

After making my notes, I was told the actually connections.

1.  Stock

2.. Occam's

3.  Occam's

4.  Stock

5.  Occam's

The actual differences were, if any, very very small, however, you might note that I picked the first four correctly and was a pass on #5, whatever that is worth.

My actual evaluation is that the differences are probably too small for me to justify spending any extra for this particular cable, and hell if I know why it should make any sonic difference at all.  However, the test results suggest I could actually hear the difference, and I did like Occam's cable slightly better.  In contrast, when I repeated the test with three tries with my assistant, he liked the stock power cord better.

My final thought is that the differences are far too small for me to consider using a "premium" power cord in production. I still think the electronic safety risks of possible wiring the cable with polarity reversed and fuse protection reduced outweighs the value of supporting an after market power cord.

However, if you feel your power cord is a cost effective improvement to your own system, then go ahead and do it.  But please make sure you maintain polarity correctly.

Thanks again for the chance to try the power cord.  it was an interesting process.

Best regards,

Frank Van Alstine

P.S.  I have managed to misplace the return shipping address for Occam's cable.  I need this to return it. 

[Occam]

Frank,

Many thanks for your evaluation. You testing methodology seems fine.
Like all true believers, I'm disappointed that my proselytizing wasn't successful, but it is what it is....

I'll PM you my return address.

Many thanks,
Paul

[rydenfan]

Frank, thanks for giving it a fair shake. The fact that you picked the correct cable on all four certainly seems to me that there is some level of audible difference.

[pardales]

Thanks to both Paul and Frank for an interesting experiment.

[topround]

Not trying to make any excuses here but maybe Franks Dac is not affected so much by power cords.
Honestly we all know they make a difference, denying it on this thread is just trying to be nice.

I(we) have heard the differences in power cords at Occams house.
It was if we all saw a UFO. I guess you had to be there, there will always those that say UFO's don't exist, but you will never convince those that have seen UfO's otherwise.

Excuse my scattered thought pattern but maybe you get my drift.?

When someone starts an argument saying there is no difference in cables, I just walk away, its like talking to a Jehovahs Witness, there just no dialectic, just words.


Mike

[BobM]

To give Paul a fair shake, the cord he sent to Frank was not one of the commercial cords he is selling at www.tweekgeek.com. Those are grounded cords. He sent Frank something completely different and more suitable for a 2 wire configuration.

Mike, you are right. Sometimes when there's little to no difference on one component (I.e. DAC) there may be a significant difference on another (I.e. Amp).

Thanks for taking the time and giving it a try anyway Frank. Maybe you will inspire other naysayers to do the same.

Bob

[funkmonkey]

Thanks to Frank and Paul for taking the time to set this up, and posting the results for the rest of us to share.  My hat is off to you both.
 
Cheers,
Greg

[Tone Depth]

It seems that Frank Van Alstine has defined to the best of his ability, a rational test methodology  for evaluating power cords.  He mentioned a similar double-blind test conducted evaluating speaker wire interconnects at the end of RMAF, in another thread.

The challenge to those whom continue to claim "we all know cords sound different" in response to his test, is to use the same rigorous double-blind approach and demonstrate whether they replicate his results, or get differing results.

[BobM]

But his actual testing results were 80% accurate that there was a difference perceived, despite his final conclusion that there was not, or not enough of one to change his mind on offering an IEC connection or different cord.

[TheChairGuy]

Frank's conclusion was much the same as I have reached with 'wire', in general.

That, I hear betterment of some kind (sometimes vague, but often can be pinpointed to louder, more bass emphasis, clearer presentation, etc), but that I cannot regularly get the same results uniformly (day to day, hour to hour) when listening and swapping out cords, IC's, etc.

So, I recognize some differences, and betterment that various wire can bring....but, I choose to be agnostic to it so that I can save my sanity trying to find the elusive and finite funds, too

This is not a shot at all at Paul/Occam (who knows he's one of my fave people here at AC ) or any 'wire' vendor (so often wrongly accused as 'Snake Oil Peddlars') or folks that can and do successfully chase down and find wire that improves their set-up.

After all, what defines value is that it makes you happy or happier when listening. My hats off to you all....wire makers and enthusiasts alike and guys that use giveaways or Radio Shack for your hookups....may you all long enjoy your audio system in good health 

John   

[avahifi]

I never concluded that there were no differences that I could hear.  Obviously I could hear differences.

My evaluation simply was that the differences were too small for me to care to pay for.  Especially in light of the fact that we can make significant improvements with rather inexpensive engineering upgrades as we learn more about circuit behavior.  In the overall scheme of things, what is most important by far is outstanding circuit designs, not the sonic virtues of the parts or wires used.

Of course one must use parts appropriate for the application.  We use 1% tolerance metal film resistors because they provide reliable, quiet and repeatable products, not because they sound better.  We desire capacitors that are not microphonic, are low inductance, insensitive to heat variations, and are durable.  The wiring must be of adequate gauge for the current requirements and be easy to strip, solder, and hold shape.  The overall unit must be stable under a wide variety of loads and be up and running properly in a matter of seconds after turn on, not requiring hours of burn in or never being shut off for fear of loosing musicality.  The unit must be as fault tolerent as we can build it, again excellent stability enhances this virtue.  Keeping all these requirements in mind in the design and build process often costs far less than a set of high end interconnect cables or speaker wires.

I do wish that more of you that are really into the sonic virtues of good sounding parts, cables, and cords would try and duplicate the double blind test procedures we use here.  We use these tests not only on cables and such, but on our own engineering efforts too.  You would be surprised to see how many good ideas we come up with in the design process simply do not show up under critical listening tests, and are discarded. I am not going to charge you for something that simply does not work well.

If the power cord would have made a reasonable difference (to my ear I thought I was hearing a VERY slightly more open and spacious sound, but then again sometimes not, and my assistant had the opposite opinion) I would look into the issue further.  But just as I would not invest in circuit upgrades that made such a small audible difference, I would not invest in cables that have no more definitive differences.

And again, your value judgements may very well be different than mine.  Thus no more carping from me about your choice of cables and interconnects but I will wince at the prices you choose to pay, and wish instead that you had seen fit to spend the money on my equipment rather than expensive cables.  I don't want to throw cold water on your party, it is your party.

Enjoy the music.

Best regards,

Frank Van Alstine

[Brown]

Very interesting and fair so far. Its simple economics. Occam cord $350 to be more. So $348 dollars in difference. A small difference in sound. To some that IS enough to justify the money. Cool. For others the money might be used for a better designed component.
  If Occams' cord [ and others ] were priced lower the debate would calm down. IMO the $2000 plus cords have put some vinegar on the wound. Most agree there is a difference in sonics its just that darn price. Why not sell direct and lower price. I would be interested in one, then. Good luck Occam and thank you Frank for your Frankness [ couldn't resist ]

[martyo]

Frank's conclusion was much the same as I have reached with 'wire', in general.

That, I hear betterment of some kind (sometimes vague, but often can be pinpointed to louder, more bass emphasis, clearer presentation, etc), but that I cannot regularly get the same results uniformly (day to day, hour to hour) when listening and swapping out cords, IC's, etc.

So, I recognize some differences, and betterment that various wire can bring....but, I choose to be agnostic to it so that I can save my sanity trying to find the elusive and finite funds, too

This is not a shot at all at Paul/Occam (who knows he's one of my fave people here at AC ) or any 'wire' vendor (so often wrongly accused as 'Snake Oil Peddlars') or folks that can and do successfully chase down and find wire that improves their set-up.

After all, what defines value is that it makes you happy or happier when listening. My hats off to you all....wire makers and enthusiasts alike and guys that use giveaways or Radio Shack for your hookups....may you all long enjoy your audio system in good health 

John  

Nicely put John.

[doak]

I never concluded that there were no differences that I could hear.  Obviously I could hear differences.

My evaluation simply was that the differences were too small for me to care to pay for.  Especially in light of the fact that we can make significant improvements with rather inexpensive engineering upgrades as we learn more about circuit behavior.  In the overall scheme of things, what is most important by far is outstanding circuit designs, not the sonic virtues of the parts or wires used.


Frank Van Alstine

A big AMEN for Brother Frank !   

"Take care of the elephants and leave the mice for later ... if you ever get to them."

Doak

[rydenfan]

Very interesting and fair so far. Its simple economics. Occam cord $350 to be more. So $348 dollars in difference. A small difference in sound. To some that IS enough to justify the money. Cool. For others the money might be used for a better designed component.
  If Occams' cord [ and others ] were priced lower the debate would calm down. IMO the $2000 plus cords have put some vinegar on the wound. Most agree there is a difference in sonics its just that darn price. Why not sell direct and lower price. I would be interested in one, then. Good luck Occam and thank you Frank for your Frankness [ couldn't resist ]

That cord cost no where near that. That was not one of the cords that Paul is selling. May want to do a bit more research on the facts first.

[lazydays]

I never concluded that there were no differences that I could hear.  Obviously I could hear differences.

My evaluation simply was that the differences were too small for me to care to pay for.  Especially in light of the fact that we can make significant improvements with rather inexpensive engineering upgrades as we learn more about circuit behavior.  In the overall scheme of things, what is most important by far is outstanding circuit designs, not the sonic virtues of the parts or wires used.

Of course one must use parts appropriate for the application.  We use 1% tolerance metal film resistors because they provide reliable, quiet and repeatable products, not because they sound better.  We desire capacitors that are not microphonic, are low inductance, insensitive to heat variations, and are durable.  The wiring must be of adequate gauge for the current requirements and be easy to strip, solder, and hold shape.  The overall unit must be stable under a wide variety of loads and be up and running properly in a matter of seconds after turn on, not requiring hours of burn in or never being shut off for fear of loosing musicality.  The unit must be as fault tolerent as we can build it, again excellent stability enhances this virtue.  Keeping all these requirements in mind in the design and build process often costs far less than a set of high end interconnect cables or speaker wires.

I do wish that more of you that are really into the sonic virtues of good sounding parts, cables, and cords would try and duplicate the double blind test procedures we use here.  We use these tests not only on cables and such, but on our own engineering efforts too.  You would be surprised to see how many good ideas we come up with in the design process simply do not show up under critical listening tests, and are discarded. I am not going to charge you for something that simply does not work well.

If the power cord would have made a reasonable difference (to my ear I thought I was hearing a VERY slightly more open and spacious sound, but then again sometimes not, and my assistant had the opposite opinion) I would look into the issue further.  But just as I would not invest in circuit upgrades that made such a small audible difference, I would not invest in cables that have no more definitive differences.

And again, your value judgements may very well be different than mine.  Thus no more carping from me about your choice of cables and interconnects but I will wince at the prices you choose to pay, and wish instead that you had seen fit to spend the money on my equipment rather than expensive cables.  I don't want to throw cold water on your party, it is your party.

Enjoy the music.

Best regards,

Frank Van Alstine

Frank,
In my two systems I use many different brands of power cords and IC's. Some are not so great and at least one is outstanding. But in source equipment I (like Frank) see very little difference between a high end cable and a good quality low end cable. Yet with my amps and preamps I have seen some differences; some kinda small and at least one was quite noticable right away. I've also noticed that tube equipment seems to reap the gains more than solid state equipment. That being said I think the shielding of the basic wire is more important than the actual copper or silver in it. Personally I more interested in the qualityof the end connectors than I am the basic wire itself.
   Many years ago Frank used to run an ad in the old Audio Magazine, and it was a true learning experience! Frank was the guy who told all of us to ditch the cheap speaker wire for zip cord (now were going back over thirty years), and I took his advice and ran with it. Then thinking more is better I took his advice a couple steps further for even more improvment (remember there really were no after market cable companys to speak of back then). Later I found this new company named Audioquest, and bought a set of their cables for further improvement. Now I've been thru the Kimbers and Cardas as well as several sets of Synergistics cables. To me the first two sounded fairly close to each other, but one was slightly more transparent. The Synergistics were better with tubes, but not a lot better than the Cardas. I now use a custom built twisted wire cable (Kimber) with WBT ends in my small system, and a pair of custom built Gronenbergs in my downstairs system with WBT connectors. Were the Gronenbergs anybetter than the Cardas bi-wires I used before? Maybe, but if they are it's extremly slight (not a fair test as the Gronenbergs are two wire). I've also had several custom built Gronenberg power cables built for me trying to find a noise problem. Did they sound anybetter? I can't truthfully say they did, but the noise went away (what I was after anyway). So what this all leads to is that I think the way power cables are insulated is more important than the alloy number (same can be said with the speaker cables after you reach a certain size and length.
   Interconnects are a different story for me. I've been thru a lot of them thru the years, and now use almost nothing but Gronenbergs (for long runs), Synergistics, and MIT's (I think they work best with tubes). All my IC's have been re-terminated with WBT ends (except for the MIT's), and here I can hear a difference.
gary

[Brown]

Very interesting and fair so far. Its simple economics. Occam cord $350 to be more. So $348 dollars in difference. A small difference in sound. To some that IS enough to justify the money. Cool. For others the money might be used for a better designed component.
  If Occams' cord [ and others ] were priced lower the debate would calm down. IMO the $2000 plus cords have put some vinegar on the wound. Most agree there is a difference in sonics its just that darn price. Why not sell direct and lower price. I would be interested in one, then. Good luck Occam and thank you Frank for your Frankness [ couldn't resist ]

That cord cost no where near that. That was not one of the cords that Paul is selling. May want to do a bit more research on the facts first.

 Chill dude sorry for the oversight. I stand corrected.  My opinion still stands though. Its the price of cords that all seem to quiver over not the results. Hey I wish him the best in his business. Look at the cord prices as of now. Manfs offering 50%, 35% off and they are still making money. If the cords were priced at today's offering more would bite.  I use ESP cords for the amps and omega active for CDP. Preamp uses ESP as well. Very happy all were bought previously owned. Price was right and results wonderfull. Just my 2 cents.

[cujobob]

Had Frank chosen his stock cable as the 'better' cable, I really do have to wonder what kind of comments we would be seeing.

Thanks Frank, for putting the effort into this.

[topround]

It would be a bloodbath

[Lancelot]

This seems to be an interesting and honest appraisal , as far as it goes.

Suppose you were going to buy a car. You test drive one then another. For arguments sake, lets say you were impressed by both but bought one for whatever reason- perhaps it was less expensive.

Now, if only you could have purchased both cars, I'm of the opinion that you would have ended up preferring one over the other for reasons not readily apparent in the test drive. Perhaps the same thing would happen with toasters.

The test drive ( with anything) can't possibly simulate the myriad of ways anything will be used, or resonded to, over the long run. Experience with something usually defines its usefulness or appropriateness for each individual.

So, IMO, short evaluations  are best to demonstrate rather substantial differences between things. In audio, subtle differences are basically the name of the game ( excepting loudspeakers) . The standard for something being *better*or *different*( assuming enough power etc.)is  often rather small and elusive.

So, given time, different electronics etc. would the results be different. I really don't know but it may be the only real way for an audiophile to determine whether any expenditure is really worth it to the only person that counts, THEM.