GR Research B24 AC Cord Review

[Katji]

A little more waffle from Danny, 5:40 on how to overfilter (with power cords?) and collapse soundstage.

Sad/depressing to see these images of audiophile neurotics showing their thick power cables.
My RSS feed has euroactive.com posts interspersed with ASR posts and although the euractiv.com images are usually dull or uninteresting, I just now saw one showing a pretty, cute president that I had not seen before. So I went to google and found that the prime minister is also pretty.

 

[dr0ss]

Cheap power cords are rubbish according to him, but why not spend even more money on power cords than Danny's costs and get even better sound than through his cords? Nop, then it can even get worse according to Danny, with too much filtering. So ... conclusion, according to Danny will be?

Or skip the cords altogether and connect the amp to the wall with blockchain.

 

[DanielT]

Or skip the cords altogether and connect the amp to the wall with blockchain.

No, it would be really bad according to Danny. The power cords filter out dirty current and no there must be power cords for that. Namely, it is not enough with the hi-fi gadget itself that filters. Watch the video and you will see that this is exactly what Danny claims.
(I do not believe in that at all, best to add )

 

[DualTriode]

..... snip

It would be interesting to compare with something like this: https://diyaudioprojects.com/Power/diyMains/ I would expect the DIY cable to perform just as well, possibly better than the fancy cable.

Tom

Hello,

There is a surplus store down the road from me with a bin full of computer power cords. I dig through the bin and pull out the cords with UL markings and labeled "shielded" and pay $2.00 each.

Cut off the cord caps and install XLR's they make good interconnects.

I often use these shielded power cords on my test bench to supply bench made power supplies or to power up DUT's.

Seems that the 60Hz and family of harmonics even high frequency switching noise gets into the inputs of many things particularly on the bench.

$350.00 is way too much, still a little shielding may help keep noise out of low level inputs.

Thanks DT

 

[amirm]

I'm also curious how you took the bin width of the FFT into account when adding the audibility curve to the graph.

I have already explained this twice. The bin width only impacts noise. That graph showed mains interference which is pure tones. They are not impacted by fft gain.

Are you really assuming I don't know such basics? So disappointing.

 

[amirm]

Was it? This is the graph I'm referring to:

Yes. It is starring you right in the face. If you know the topic you need nothing else. Amazes me that I just explained all this and you still ask the question.

 

[tomchr]

All it says is "referenced to 120 dB playback" but where does the curve come from? Why was 120 dB chosen. I thought you were referring to the Fletcher-Munson curves, but you were actually referring to something else. See the issue? Am I expecting too scientific of an approach here?

Tom

 

[tomchr]

Seems that the 60Hz and family of harmonics even high frequency switching noise gets into the inputs of many things particularly on the bench.

I built some star quad cables for exactly that reason.

Tom

 

[amirm]

All it says is "referenced to 120 dB playback" but where does the curve come from? Why was 120 dB chosen. I thought you were referring to the Fletcher-Munson curves, but you were actually referring to something else. See the issue? Am I expecting too scientific of an approach here?

Tom

If you know the topic, then you should not have any of those questions. If you don't know the topic, then you should simply ask and not claim as you are doing here again, that arbitrary decisions were made.

I will answer but hopefully any follow ups would be after you read my article and references I provided.

Fielder (ex president of AES and Dolby Fellow) researched a number of live concerts and determined that peak playback level in his standard seat reached and slightly exceeded 120 dBSPL. As a result, if we want to reproduce that live experience, we need similar dynamic range. This sets the upper bound on playback level. The lower bound is threshold of hearing per Fletcher-Munson. Care must be taken to not compare noise with Fletcher-Munson due to this having been determined using pure tones. In my case, the concern was audibility of mains spikes which are not impacted by this factor. Once you have max playback and minimum, then you have the required dynamic range.

 

[tomchr]

I apologize for trying to learn.

Any scientific paper I've ever read has had a References section. That's really handy for those, "hmmm... Where did this come from?" types of questions. But I guess those questions aren't welcome here. That's pretty sad actually.

Tom

 

[Erici]

I apologize for trying to learn.

Any scientific paper I've ever read has had a References section. That's really handy for those, "hmmm... Where did this come from?" types of questions. But I guess those questions aren't welcome here. That's pretty sad actually.

Tom

I think the problem is not asking questions but your statements like "Am I expecting too scientific of an approach here?"
That is a statement masquerading as a question.

 

[voodooless]

I think the problem is not asking questions but your statements like "Am I expecting too scientific of an approach here?"
That is a statement masquerading as a question.

It literally has a question mark…

 

[Erici]

It literally has a question mark…

But the way I read this is that he is stating that the site is not very scientific, which is not the case.

 

[voodooless]

But the way I read this is that he is stating that the site is not very scientific, which is not the case.

Might be a problem with your reading? If his observation is that ASR is not a scientific journal, he’s very much correct.

 

[Azathoth]

It sounded to me like @Azathoth was being a bit hard on himself and blamed the fact that he perceived a difference with the fancy cord on having a failing memory, failing perception, or (my extension) failing intelligence. I see this sentiment quite a bit, in particular in "subjective vs objective discussions" and I find it concerning.

Tom

Funny you would see it that way, I am just amused that we are fallible beings and our species is prone to nonsense like this. Nothing to do with me being hard on my self!?

 

[tomchr]

Yeah. I tend to bristle at having words put in my mouth. That will often cause me to engage in communication on multiple levels simultaneously. My bad.

My goal: To encourage more scientific communication rather than communication in absolutist statements. "If you'd bothered to read, you'd already know..." doesn't go very far for me. Once a reference list has been compiled it takes very little effort to refer to it. That's easy to do with a footnote or a link to a web page. In fact, that's way less effort than repeating, "if you'd read..." ad nauseam.

But the way I read this is that he is stating that the site is not very scientific, which is not the case.

I find this site is drifting further away from science. I commend Amir for his efforts, for his measurements, and for his attempts to put the measurements into context, but I think there's room for improvement.

ASR is not a scientific journal (and - in my view - should not be), but it does have the word 'science' in the name, so I think I'm reasonable in my expectations that there be some scientific content, including references to established science. Otherwise, it's a bunch of measurements with some discussion added. And maybe that's the goal. Maybe I'm interpreting too much from the word 'science'.

Above is my opinion based on my observations of the culture here since 2018. It is my opinion and my opinion only. I am not expecting anybody to make any changes they are unwilling to make based on me expressing my opinion, though I am hoping that they take my opinion and suggestions into consideration. But ultimately, it is not my forum and not my culture to drive or nurture. In my observation the culture here is drifting closer to the culture of SBAF and I find that concerning.

Tom

 

[tomchr]

Funny you would see it that way, I am just amused that we are fallible beings and our species is prone to nonsense like this. Nothing to do with me being hard on my self!?

Maybe I was projecting... (And, no. I'm not that much of a Freudian).

Tom

 

[Doodski]

I find this site is drifting further away from science. I commend Amir for his efforts, for his measurements, and for his attempts to put the measurements into context, but I think there's room for improvement.

ASR is not a scientific journal (and - in my view - should not be), but it does have the word 'science' in the name, so I think I'm reasonable in my expectations that there be some scientific content, including references to established science. Otherwise, it's a bunch of measurements with some discussion added. And maybe that's the goal. Maybe I'm interpreting too much from the word 'science'.

I notice this too. There are many new members that are subjectivists that are here for info and learning although they wear down some of us and we bend a bit to avoid running them out of the website as they sometimes feel too much pressure and receive aggressive negative commentary too. It's a fine line making them feel comfortable while simultaneously attempting to bring them up to speed on what ASR is about.

 

[tomchr]

I agree with that statement as well. But I will also point out that the world is more nuanced than a dichotomy. I used to be a hardcore objectivist. If it couldn't be measured, it couldn't be perceived. Through my psychology degree (and also through discussions here) I have developed a more nuanced approach. I touched on some of that in my comments here yesterday.

I love the intersection between engineering and the science of psychology. And, yes. Psychology is a science. It uses the scientific method. I learned vastly more about science in my psych degree than in my engineering degrees. Go figure...

Tom

 

[DualTriode]

Hello All,

The “Threshold of hearing Curve” crosses 1000Hz at 0 SPL.

The Threshold of Hearing is often stated as 0 SPL. (A relative dB scale)

The “Threshold of Hearing” needs a closer examination. The TH was empirically measures in a dead quiet space. The typically quiet listening room will have a SPL somewhere in the 40dB SPL range. Tones that are well above the TH will be masked and not audible in the typical listening room.

“Threshold of Hearing” and audibility are two different things.

The graphic uses an arbitrary dBrA scale that places ~3kHz at -120dBrA’s. By looking at the face of the graphic the -120dBrA appears to be picked from the sky without explanation and treated as thou shalt not ask without fear of being insulted. I believe that the dBrA scale is confusing to most readers.

Placing the “Threshold of Hearing Curve” on top of a FFT requires much more explanation if Engineers are labeled “confused” by what it is trying to communicate.

Just my opinion

DT