[Marbles]

Lightfire...you have a PM..

[Joules]

Oh Oh - someone's in trouble ...

[WOR Radio]

Time travel is real....I know it is because....everytime i travel, it takes time!

(Also, a recording made 2 years ago can suddenly arrive here in the present and instantly, this is a good lesson in time travel no?)

[NewBuyer]

I don't know LightFire, but judging from the upset responses he's getting, it seems he is touching a nerve here regarding his suggestion about performing controlled listening tests. Perhaps there is some forum history going on here that I am unaware of? [His posts in this thread don't seem inflammatory.]

It was mentioned earlier in this thread, that RFI is in fact blocked by the equipment transformers, but the line run from power-cord input to transformer might still radiate RFI into the chassis/internals and cause problems, specifically, could cause op-amp oscillation.

Is RFI the major culprit then, that conditioners aim to reduce? If so, why not just put a ferrite on the line run in question, or even on the power cord, and eliminate the conditioner units?

What are the noise frequencies that we are worrying about here (regarding op-amp oscillation risk, etc) - are they in the MHz ranges, or are they down in the kHz ranges?

[Marbles]

Newbuyer..these posts were split from the original thread that contains the posts you reference...maybe you should make your post in that original thread 

[NewBuyer]

Newbuyer..these posts were split from the original thread that contains the posts you reference...maybe you should make your post in that original thread 

Thanks! Just did.

[JDUBS]

Lightfire, we determined long ago that AC would be a double blind test free zone...please refrain from posting re: DBX's in the future.

When did you guys determined that and why?!

4 years ago...Because it only leads to augments with no resolutions.

It actually leads to resolutions. If there is an audible difference we must be able to prove it beyond doubt.
I didn't see any official rule about "no ABX allowed" so I will chose to ignore it. Now if you guys want to make it official and ban the only existent reliable tool to differentiate between what really makes an audible difference and what doesn't. Then you should also change the name of the site to "The Subjective Audio Circle".

Yeah...change it to "The Subjective Audio Circle".  That's a riot!!    You're not going to change how things are done around here, so why hang out here?   

[LightFire]

Lightfire, we determined long ago that AC would be a double blind test free zone...please refrain from posting re: DBX's in the future.

When did you guys determined that and why?!

4 years ago...Because it only leads to augments with no resolutions.

It actually leads to resolutions. If there is an audible difference we must be able to prove it beyond doubt.
I didn't see any official rule about "no ABX allowed" so I will chose to ignore it. Now if you guys want to make it official and ban the only existent reliable tool to differentiate between what really makes an audible difference and what doesn't. Then you should also change the name of the site to "The Subjective Audio Circle".

Yeah...change it to "The Subjective Audio Circle".  That's a riot!!    You're not going to change how things are done around here, so why hang out here?   

We still have hope. Not everybody in this forum is subjectivist! Repent from your subjective sins JDUBS and come to the light! 

[lonewolfny42]

Whats all this stuff about double blind testing.........

(Trust me thats blind....no glasses and a blindfold....but I could hear... )

[Marbles]

Lightfire, the reasons we implemented the policy are because:

Most comparisons are sighted, so invalidated by the DBX'ers.
Single blind are difficult to do in the home and are invalidated by the DBX'ers.
DBX tests are almost impossible to do in the home and take great care to set up.  Almost every in home DBX posting I have ever seen has been attacked because of the methodology, so invalidated.

Most all "professional" DBX's (except for a small handfull)  have been attacked for their methodology and these took months and months of preperation.

Therefore it makes no sense to discuss DBXing at all since it does nothing but discourage the postings of reviews and comparisons.

Most all reviews and comparisons discuss the methodology.  You can dismiss or accept the review or comparison based upon this.  If it nullifies all reviews on this site for you, then so be it.

[LightFire]

Lightfire, the reasons we implemented the policy are because...

The way you talk it looks like I am forcing everybody to go trough an ABX for every claim they make. This is absolutely not true.

I know in some circumstances is quite difficult to implement those tests (but in the power cord case it should be quite easy). What I find strange is that from all people that claims a certain power cord superiority of some kind no one tried do perform this (in this case) simple test! Specially because from the electrical engineering point of view the claim that a power cord made of silver makes a sound system sound different than a power cord made of copper is outrageous!!

[JohninCR]

I pose a simple question to all the "believers" out there.  Do you accept that things like mood and expectation can influence a person's perception of what they hear, or do you dismiss this as rubbish and you hear what you hear period?  If you accept this concept, how can you "know" if there's a change without valid testing.  If you reject this well known and scientifically studied phenomenon, then it's you that is closed minded, not the objectivists.  The profound differences that some claim is downright silly.  Things that make profound differences would obviously be included as standard equipment design, and btw, they already are.

[arthurs]

This is one aspect of audio boards that gives me tired-head...okay, on 3...everyone believe whatever the hell floats your boat, it's your money and if it makes you happy and you believe it does something for you...good for you, I have no need to prove you wrong or have you prove to me what you think you hear, I accept it as yours.......1....2....3....

[Occam]

....I know in some circumstances is quite difficult to implement those tests (but in the power cord case it should be quite easy)....

Quite easy? Do tell.
Please show me a such switching schema, sbt is fine, that would allow non interrupted comparisons. We wouldn't want to corrupt the validity of the test by having to rely upon aural memory beyond 5 seconds now, would we? So your 'easy' mechanism allows you to switch power cords on a cd player while a track is playing, or paused and then within a few seconds, continued?

Have you ever actually implemented any such switching mechanisms? Have you actually participated in any sort of blind testing? Or is all this palaver a repeat of what you've read on other boards?

Talk is cheap.

TIA,
Paul

[slbender]

While I myself even go to extreme and say I was "blown away" by some large audible change ( the first time I listened to my Flea Power SET Amp I was very impressed, I had expected it to sound bad or very bad, but it was impressive compared to various PP tube amps and various transistor units ).  But actually aural memory is a rather tricky and difficult task, and decidedly complicated by factors most people don't even consider.  Many times I think in cases of audible change in reality, it is the listener who has changed, NOT the equipment.

I did grad work in Audiology, which deals with hearing, where various courses deal with the anatomy and physiology of the hearing mechanism, etc. which has given me insight on how non-linear, and non-flat the ear's response is ( hence those Fletcher-Munson curves ).  So a few dB here or there plus or minus and we seem to hear great changes.  However, such changes in themselves could also be due to... the listener unconsciously swallowing and changing the air pressure in the middle ear; or whatever he smoked, drank, or ingested a half hour ago taking effect.  Or changes in normal barometric pressure from one minute to the next.  Or positional changes - diffraction patterns, moire, and phase patterns due to interference effects can radically change with as little as a fraction of an inch or a few millimeters positional change in your chair or listening position, be it horizontal or vertical. Also, the interaural angle... did you turn your head slightly off axis or on axis for the next listen?  Huh, huh ?

So unless one is severely restrained in the same spot, using some metal braces, ropes, seatbelts and all sorts of paraphernalia, quite literally, 90+% of the time, once you go and change things, it is YOU who have changed position in three dimensions, that has changed how you perceive the sound, and THAT makes a whole lot of difference.  So chances are ... the equipment has not changed the sound at all, but YOU have changed position and internally and you hear THAT!

Unless... you have a team of well trained serfs and scientists to tie and restrict you to an unmovable  listening position and carefully maintain the air pressure and barometric environment, maintain a reference SPL at your nose, and then rule out middle ear pressure changes ( and somehow prevent you from swallowing  - ha! ) then with the serfs implementing your change of cables and ABX stuff and such... I'd have to say most audible improvements or changes people report are truly bogus. 

Lastly, sight and sound are not equal senses.  Sound is there and then its gone; visually, well one can freeze a DVD and inspect a part of a frame of video over time and make comparisons, sound is continuous and discontinuous, and what came before actually affects what comes after, and what comes after, affects how we perceive what came before.  Confused.  Yup!@@!  In terms of phonemes and musical detail it alters itself, the before and the after.  Takes years to figure out, so go figure ?  In other words, there can really never be an exact beyond any doubt answer, only generalizations that you may agree with or disagree with. Sorry almost nothing can be proven by ABX, DBX, because everyones hearing and frequency response is actually different in both threshold and perception at any one system SPL loudness level. And these are my final words on this... it's all about the music, to all a happy new year and happy listening.


-Steven L. Bender, Designer of Vintage Audio Equipment

I have a strong appreciation for sound engineering principles, yet have found it very difficult to ignore what I believe I hear when experimenting with power cords, conditioners, cables, break-in, etc.  Sometimes, the differences are small enough for me to believe I'm imagining the differences.  Other times, the differences are so significant that I believe I'd have to be insane for them not to be real differences....

[Daygloworange]

Just for the record, last week I participated in a double blind test of power cords on a fellow AC members audio system. I played fair, and asked that they switch randomly back and forth between two power cords and take notes. Although I didn't have time to really get used to the sound of the system (it was a high end system with Classe amps, Audio research pre, Martin Logans ), I thought I heard subtle differences. Thought I heard them fairly clearly. They were minute, I thought, hearing them primarily in the vocal region on a particular Steve Winwood track that I'm very familiar with, and perhaps in low end extension.

When we tallied it up, the results were inconclusive. I wasn't able to consistently do it. I still think that testing these kinds of things is very difficult, for the reasons many have discussed in this thread, as well as numerous other threads on the topic. I'm still left with the thought that how would it work if I did it with my system? Was I focused enough? Was I too focused? If we hadn't tallied it up, I would have been sure that I heard a difference.

I'm still opened minded on all the topics, be it power cords, IC's, SC's. In over 25 years as a musician, and over 20 as a recording engineer and recording enthusiast, I can think of literally hundreds of examples of things that are, that shouldn't be, that weren't, but should have been.....

It is practically impossible to prove any of these without a doubt, the factors of the science of how you test for this, how you set up the tests, how you conduct the test, the human factors.....

I do remember years and years ago, when I first started recording with a reel to reel 4track recorder, I couldn't tell the differences between 2 microphones. A microphone was a microphone was a microphone. As you work at it for years and years, you can tell between 5 microphones of the same make and model. The differences do exist. Period. They can be heard by the human ear, and they can be recorded.

I will always remain with a healthy dose of open mindedness. I prefer not to close my mind off. It's always worked to my benefit. I encourage everyone I talk to about these things, to just have fun with it and don't take it and yourself so seriously, that actually might help in you being able to hear something, and make a believer out of you.....or not.

FWIW, I will still test these things from time to time, just for fun, as I don't lose sleep over these things one way or the other.

Cheers

[Daygloworange]

slbender,

Very nice post. I have some experience on some of what you discuss, and I agree with everything you said. I just couldn't word it as well. Thanks for your contribution to this thread.

Cheers

[shep]

I doubt if this will add anything but MY hackles get raised everytime this topic comes up and ends in conflict and attitudes and then disappears again until...this is a sort of twilight zone where belief systems
are put into question and suddenly there is no consensus, just taking sides. I'm no different. I long ago took my side so I admit to a bias. What I do notice, time and again, is how the notion of pleasure and excitement suddenly disappears. Those who insist on proof about real (or imaginary) differences appear to me very rigid and judgemental. That is their right of course, but I refuse to be categorized as deluded or misguided or just plain stupid because I not only consistently hear differences (in cables, caps, resistors etc.) but I take PLEASURE in doing so and I enjoy the element of mystery (or voodoo if you prefer) that accompanies this process. I am not unwilling to learn that what I appear to hear is part of a very complex set of variables, some of which I have no knowledge of or control over. That is part of the fun. I just wish those who are so demanding of proof and scornfull when it is not forthcoming would take a deep breath and remember to factor in enjoyment and suspend disbelief. Their hearing might improve dramatically!
Sorry to butt in...yet again

[JLM]

I've heard the effects of dirty A/C when nearby old/light industries shut down after 11 pm.  And I've heard no effects from the use of a popular and fairly pricy regeneration/conditioning device at home.  Even tried battery powered music server and amp for a while.  I picked up a local FM station (-20 dB) via a DIY chip amp that had a separate power supply with a bad (-40 dB) 60 Hz hum.  But I've never heard the effects of dirty power wherever I've lived and have never heard RF/EMI from manufacturer built equipment.  Just my experiences over the decades.

[Dan Banquer]

I've heard the effects of dirty A/C when nearby old/light industries shut down after 11 pm.  And I've heard no effects from the use of a popular and fairly pricy regeneration/conditioning device at home.  Even tried battery powered music server and amp for a while.  I picked up a local FM station (-20 dB) via a DIY chip amp that had a separate power supply with a bad (-40 dB) 60 Hz hum.  But I've never heard the effects of dirty power wherever I've lived and have never heard RF/EMI from manufacturer built equipment.  Just my experiences over the decades.

I think you have brought out a good point. If the AC lines are not "polluted" with excessive noise than the filtering a power conditioner can provide does not really come into play. However, for many of us who live in suburban or urban areas the noise on the AC lines is a fact of life.
But there is one thing to be considered: It's nice to have surge suppressor in line just in case; otherwise you could be asking yourself the following.
What is the sound of a blown power supply?
What is the sound of cash flying out of my wallet for repair bills?
How cheap was a decent surge suppressor compared to the price of fixing blown equipment?

                    d.b.