Nearly all manufacturers do not advertise/exhibit their product measurements? Why?

@fleschler 

2. As to the ragged frequency response so obvious in the bass, I had two friends accompany me pre-power cable change and the Golden Ear remastering engineer friend blurted out that it sounds terrible. He is high functioning slight autistic so he just let loose. We heard as well but didn’t know why with such great gear. 

You didn't know?  Every system, and I repeat, every system out there will have uneven bass response regardless of price once placed in a room.  Below transition frequencies of a few hundred hertz, the room dominates the frequency response of the speakers.  You can pour millions of dollars into electronics and speakers and it will not be fixed.

The cheapest and one of the most effect solution is equalization which sadly many subjectivists audiophiles don't deploy.  With it, you can pull the peaks down and not only make the response more even, but also reduce the distortion from the speakers.

You can attempt to use acoustic products as well but the wavelengths are so large and energy so huge that you can barely make a dent in it < 100 Hz.  By the time you put enough of them in there you room can wind up too dead which is unpleasant especially for acoustic/orchestral/big band music.

A power cord will do absolutely nothing for this as this effect (modal response).  Yes, you can imagine that the bass has gotten "tighter" post such a change but it is a false impression which disappears after the psychological effect of the change is gone.

If you disagree, post a before and after frequency response measurement of your room with or without your favorite power cable.  

If this knowledge is new to you, I highly suggest reading Dr. Floyd Toole's book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms

The book costs much less than the money that was wasted on said power cords.

@amir_asr

After having read your reply and getting past the fake outrage, your answer is "No." , you do not check. That is alright, but it will always leave you open to questions.I say fake outrage because no allegation or insinuation was made; a simple question was asked. I could say that you protest too much.

Now some advice for you. If you got off your high horse and allowed some discussion in ASR, none of these threads would ever have materialised. It is your arrogance and intransigence in throwing off anyone who disagrees with you that annoys many people including your own minions. Look at your appalling treatment of restorerjohn, (yes I know you did not ban him, but you dismissed him in a particularly nasty way), on your own site. This was a disgrace.

One final point. :You stated: "Keep in mind that these are not mechanical product subject to large variations. Yes, there can be minor differences in performance of components but nothing significant can be achieved."

Amir this is blatant nonsense. Are you saying that adding better quality capacitors, improved shielding,  an improved power supply, high voltage transformers and decoupling the power supply does not lead to a significant improvement?

@laoman 

Amir this is blatant nonsense. Are you saying that adding better quality capacitors, improved shielding,  an improved power supply, high voltage transformers and decoupling the power supply does not lead to a significant improvement?

First, you don't seem to follow the discussion.  Poster claimed that power cables cure modal response of the room.  They do not in any form or fashion.  Physics dictate that.  

As to your new independent claim,  you are being very vague.  Of course a good power supply needs to be designed internal to your audio gear for it to perform well.  This is mandatory.  Once there however, you screwing around with power cables, filter, conditioners, etc. is all useless.  Completely useless.  I have shown this extensively across countless products I have tested.

The best test of this is on purpose feeding audio gear highly distorted AC.  My lab AC generator can produce chopped AC.  When I feed that to decently designed audio gear, it makes zero change to its output.  As it should be.  No decently designed power supply assumes clean AC.  It converts AC to very clean DC so anything you do up front is useless. See: 

This is the AC quality in my my house:

I changed that to this chopped AC:

Look at how much more distorted the waveform is.  Yet it made no difference whatsoever to the soundwaves out of the audio gear.

No impact whatsoever.  If this didn't change the sound, what on earth do you think a different power cable does???

In every review of cables, I show measurements of the cables themselves as well.  Many times they don't even do the things you think they are doing!  In a number of cases, they are more susceptible to noise than other way around.  You are a complete victim of power tweak companies if you think any of them improve the sound of your system.  

Be a good consumer: ask these companies to provide measurements and controlled listening tests.  Don't become their PR people, making arguments that have no foundation in reality like what I am responding to.

If you rather watch a video, here it is as well:

@russ69 , thank you for your thoughtful and articulate response, What did you think of the idea of checking customer reviews? I use Mogami cables and we both seem to like them. I personally found that attention to power was a good idea but totally subject to your grid and the wiring in your home. I don’t have dedicated circuits but try to work around it as best I can.

As for speaker/dsp/room I like the idea of starting with the room, then DSP to dial it in. That was the exact method shared by Jeff Clark of Audyssey and Phil from Sound United. I got the best results with the pro version of Audyssey and this is video where they both laid that road map. Even if you don't use Audyssey this is a good resource, FWIW Jeff did reply to my e-mails and seemed to really care about their customers: