Op-Ed: Why High-End Audio is Riddled with Snake Oil - Page 16 - AVS Forum | Home Theater Discussions And Reviews
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post #451 of 592 Old 02-18-2018, 02:10 PM
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Originally Posted by alan0354 View Post
First all, every company measure with a resistive load, mostly 8 ohms. I use 4 ohms to measure, this will almost double the THD reading to make it the worst case. If I do 8ohm, the measurement is even better.

As I described in detail, you cannot simulate the speaker load. To simulate a single speaker is very easy. Simulating a multiway speaker is hard and not representative. The worst are the 3 ways high end speaker with complicate crossover network that use low loss components.
Can I assume you are measuring at least through your custom speaker cables? Otherwise how are you quantifying the cable improvements? No, you can't perfectly simulate a speaker load. But you can get a lot closer to reality than a 4ohm resistor and many companaies use do speaker simulators.

If you are measuring this ultra low distortion across a resistor, that's still good. But it proves nothing about your speaker cables lowering distortion. You have presented some theory but no measurements when it comes to the amplifier speaker interface.
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post #452 of 592 Old 02-18-2018, 02:40 PM
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Originally Posted by markrubin View Post
thanks but I am not the thread starter
Sorry, you are right but one of your mods did. I think it was a very questionable decision based on the history of this subject material.

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post #453 of 592 Old 02-18-2018, 02:43 PM
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Originally Posted by MSchott View Post
Sorry, you are right but one of your mods did. I think it was a very questionable decision based on the history of this subject material.

Actually, OP Mark Henninger is one of two editors with Scott Wilkinson being the other (I don't think there are any others?).

Moderators are a very different function and there's likely a firewall between the two functions as there is in most other online forums.
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post #454 of 592 Old 02-18-2018, 02:44 PM
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Quote:
Originally Posted by alan0354 View Post
Everyone here are speaking about their experience, no different from me.

...
Actually, no. Some discuss scientific testing that has been done, rather than just their own subjective experience. There is a world of difference between these two things.

There are some things that people have been able to distinguish in level matched double blind tests. And there are some things that no one has been able to distinguish in level matched double blind tests. So when someone tells us that they can hear a difference in a situation where the difference is such that people have demonstrated an ability to hear a difference, their story is generally believable. But when someone claims to hear something that no one has ever properly demonstrated the ability to hear, no person of sense takes them seriously, until they prove it in proper conditions. This is exactly like a case of someone claiming to be able to run 100mph. Since no one has demonstrated such an ability, no one of sense would believe such a claim, until someone proved they could do it.

So when you or anyone else claims to hear something, whether reasonable people take such a claim seriously or not is going to depend on whether it is the type of thing that people have demonstrated an ability to do or not. If no one has shown that a human is capable of doing whatever someone claims to do, sensible people will not believe that their story is true. This will be particularly true when the person in question demonstrates a failure to understand the concept of human bias and the need for proper testing.

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post #455 of 592 Old 02-18-2018, 02:48 PM
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Quote:
Originally Posted by Glimmie View Post
Can I assume you are measuring at least through your custom speaker cables? Otherwise how are you quantifying the cable improvements? No, you can't perfectly simulate a speaker load. But you can get a lot closer to reality than a 4ohm resistor and many companaies use do speaker simulators.

If you are measuring this ultra low distortion across a resistor, that's still good. But it proves nothing about your speaker cables lowering distortion. You have presented some theory but no measurements when it comes to the amplifier speaker interface.

Here I am not talking about speaker cable anymore, yes I use the custom speaker cable. I use the metal film resistor as load.

That's the thing, with the linear resistor, speaker cable is not important anymore, but I still use the custom cable.

All I talk about speaker cable is about lowering the series impedance of the speaker cable. This is shown in the drawing and the voltage divider calculation in post 430.

As I explain the difficulty of using the real speaker as load. I don't want to blow my speaker and even if I measure, it's only data for my particular speaker.

You qualify each component, for qualify amps, I use resistor load so the only one generate THD is the amp. I want to find out the THD of the amp. To the best of my knowledge, all amp manufacturers spec THD with resistor load, no speaker simulator load.

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Last edited by alan0354; 02-18-2018 at 05:39 PM.
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post #456 of 592 Old 02-18-2018, 02:50 PM
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Originally Posted by Jack D Ripper View Post
Actually, no. Some discuss scientific testing that has been done, rather than just their own subjective experience. There is a world of difference between these two things.

There are some things that people have been able to distinguish in level matched double blind tests. And there are some things that no one has been able to distinguish in level matched double blind tests. So when someone tells us that they can hear a difference in a situation where the difference is such that people have demonstrated an ability to hear a difference, their story is generally believable. But when someone claims to hear something that no one has ever properly demonstrated the ability to hear, no person of sense takes them seriously, until they prove it in proper conditions. This is exactly like a case of someone claiming to be able to run 100mph. Since no one has demonstrated such an ability, no one of sense would believe such a claim, until someone proved they could do it.

So when you or anyone else claims to hear something, whether reasonable people take such a claim seriously or not is going to depend on whether it is the type of thing that people have demonstrated an ability to do or not. If no one has shown that a human is capable of doing whatever someone claims to do, sensible people will not believe that their story is true. This will be particularly true when the person in question demonstrates a failure to understand the concept of human bias and the need for proper testing.
That's why I encourage people to build the cable and try. $30, 1 hour time. Talk is cheap. If all else fail, one still have an extra pair of cables.

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post #457 of 592 Old 02-18-2018, 02:57 PM
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I guess this conversation is going nowhere. I cannot do DBT, you guy totally invalidate my experience, if you don't want to try the cable. There's not much more to talk anymore. We each just hold on to our believe, no lost on my part. I though I share my experience that might benefit someone.

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post #458 of 592 Old 02-18-2018, 03:10 PM
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Quote:
Originally Posted by alan0354 View Post
That's why I encourage people to build the cable and try. $30, 1 hour time. Talk is cheap. .
Provide detailed plans (pictures, parts, etc.) on your design. When others try, they will/can share their experience(s).



If you can’t explain it simply, you don’t understand it well enough – Albert Einstein
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post #459 of 592 Old 02-18-2018, 03:19 PM
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Quote:
Originally Posted by alan0354 View Post
I guess this conversation is going nowhere. I cannot do DBT, you guy totally invalidate my experience, if you don't want to try the cable. There's not much more to talk anymore. We each just hold on to our believe, no lost on my part. I though I share my experience that might benefit someone.
How about acknowledge, when you put forth your experience, that there may be some perception bias at play? After all, every human is susceptible to it.
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post #460 of 592 Old 02-18-2018, 03:36 PM
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Quote:
Originally Posted by alan0354 View Post
You qualify each component, for qualify amps, I use resistor load so the only one generate THD is the amp. I want to find out the THD of the amp. To the best of my knowledge, all amp manufacturers spec THD with resistor load, no speaker simulator load.
OK, so then you are just doing what every other amp manufacture does. Congrats on your ultra low distortion although we would really need to see more information such as power levels and response, but anyway.....

Your claims about speaker cables are also no different than the audiophile industry as a whole. Plenty of theory, some of yours good. But absolutely no measurements to back them up other than what you say you heard.
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post #461 of 592 Old 02-18-2018, 04:05 PM
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Originally Posted by alan0354 View Post
That's why I encourage people to build the cable and try. $30, 1 hour time. Talk is cheap. If all else fail, one still have an extra pair of cables.
Do you not see the difference between someone trying something at home and a rigorous scientific proof of something?

When considering whether a new medicine will work or not, do you think that we should randomly try it ourselves, without any controlled conditions, or do you think it would be better to examine a scientific study (or more than one) of its efficacy and safety?


Also, we all know how this will work in practice. If the person makes the cable, and does some proper testing (which we know most people will not), and no one hears any difference, you can always say that the other equipment was not good enough, or that it was not set up properly, or that the cable was not properly made, or that the people have poor hearing. So for you, there is no risk involved in suggesting that others make it.

Since you are the one claiming it makes an audible difference, it is up to you to prove that it does. It is not up to us to prove anything. And if you refuse to bother with actual evidence, you ought not be surprised if people ridicule you (though people at this site ought to take care to make sure that they do not violate forum rules in what they say). Just like someone might if you went to a running website and claimed that your new design of shoes made you capable of running 100 mph, but did not actually have any real evidence of the claim.

If you want me to illustrate this further, suppose I were to claim that I could hear the wings of a gnat at 100 miles away. Would you believe me? Suppose I claim that only cables that are soaked in the menstrual blood of virgins are good enough, and that I can clearly hear the difference when one uses the blood of nonvirgins instead; would you believe me? If so, why? And if not, why not?

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post #462 of 592 Old 02-18-2018, 04:09 PM
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post #463 of 592 Old 02-18-2018, 04:14 PM
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Originally Posted by Scotth3886 View Post
Actually, OP Mark Henninger is one of two editors with Scott Wilkinson being the other (I don't think there are any others?).

Moderators are a very different function and there's likely a firewall between the two functions as there is in most other online forums.
Not really the point. An admin here started this thread and I'm sure he was aware that it had a good chance of getting off topic and needing heavy moderation when he did so.
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post #464 of 592 Old 02-18-2018, 04:16 PM - Thread Starter
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Originally Posted by MSchott View Post
When you started this thread you must have known how it would evolve.
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Originally Posted by markrubin View Post
thanks but I am not the thread starter
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Originally Posted by MSchott View Post
Sorry, you are right but one of your mods did. I think it was a very questionable decision based on the history of this subject material.
Quote:
Originally Posted by Scotth3886 View Post
Actually, OP Mark Henninger is one of two editors with Scott Wilkinson being the other (I don't think there are any others?).

Moderators are a very different function and there's likely a firewall between the two functions as there is in most other online forums.
- Bingo. For me, success IS a thread that (potentially) requires heavy moderation because it creates a vigorous discussion and generates the traffic that goes with such discussion.

My forum threads are created as the "comments section" for homepage posts.

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Not really the point. An admin here started this thread and I'm sure he was aware that it had a good chance of getting off topic and needing heavy moderation when he did so.
Huh? I'm Senior Editor of the site. I'm not a mod and I'm not an admin.

I am aware that these discussions get heated. When you have this many comments and participants, it's easy for a thread to go off topic, or for the discussion to get caught up in a sub-topic.

Any thread can go off topic. Predicting the long tail of thread like this is like predicting the path of a hurricane.

Fact: 13,000+ views and 460+ comments in under a week in this sleepy sub-forum = a good choice of subject matter.

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Last edited by imagic; 02-18-2018 at 04:30 PM.
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post #465 of 592 Old 02-18-2018, 04:52 PM
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[QUOTE=golfster;55682058]How could I have forgotten about this item. Be sure to read the customer comments. "made a bigger improvement in sound quality than the last $1000.00 interconnect cables I purchased"
http://www.machinadynamica.com/machina31.htm[/QUOTE

I can't believe people actually purchased this stuff. Worse yet, that they claim to hear an actual difference before and after using the "equipment". I understand that confirmation and expectation biases can be powerful, but still. These comments defy logic and reasoning.
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post #466 of 592 Old 02-18-2018, 05:04 PM
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Originally Posted by imagic View Post
I try not to ever forget that. Indeed, my retort to every "where's the harm done" comment is... what if the person buying snake oil solutions spent something other than PURELY discretionary income on it... because they bought into marketing designed to exploit the egos of rich audiophools?

I'd rather not see that sort of thing happen.
Consenting adults need to take responsibility for their own foolish purchases. If they can't afford the snake oil, then they shouldn't be buying it.
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post #467 of 592 Old 02-18-2018, 05:04 PM
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Originally Posted by Glimmie View Post
OK, so then you are just doing what every other amp manufacture does. Congrats on your ultra low distortion although we would really need to see more information such as power levels and response, but anyway.....

Your claims about speaker cables are also no different than the audiophile industry as a whole. Plenty of theory, some of yours good. But absolutely no measurements to back them up other than what you say you heard.
THD measured at 4ohm 65V peak to peak, that is 132W output power. About 0.001%@1KHz, [email protected] Gradually increase from 1KHz to 20KHz. That is about 0.0025%@10KHz or so.

The difference between me and the audiophile industry is I am trying to tell you to build a pair yourself for $30, they are trying to sell you a pair for hundreds of dollars. I am actually trying to debunk them using theory and experiment. I am not with them if you stop and think about it. So please don't put me with those companies.

Hell, you can't build a pair with Monster 12 gauge cable much cheaper than what I suggested!!! If this is snake oil, it's really really cheap snake oil.

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post #468 of 592 Old 02-18-2018, 05:08 PM
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Originally Posted by Jack D Ripper View Post
Suppose I claim that only cables that are soaked in the menstrual blood of virgins are good enough, and that I can clearly hear the difference when one uses the blood of nonvirgins instead; would you believe me?
He, he, he......gross.....

[quote=Dark Matter;55716026]
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Originally Posted by golfster View Post
How could I have forgotten about this item. Be sure to read the customer comments. "made a bigger improvement in sound quality than the last $1000.00 interconnect cables I purchased"
http://www.machinadynamica.com/machina31.htm[/QUOTE

I can't believe people actually purchased this stuff. Worse yet, that they claim to hear an actual difference before and after using the "equipment". I understand that confirmation and expectation biases can be powerful, but still. These comments defy logic and reasoning.
Wait, that is NOT a serious website, is it? You're kidding, right?
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post #469 of 592 Old 02-18-2018, 05:09 PM
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Originally Posted by Ratman View Post
Provide detailed plans (pictures, parts, etc.) on your design. When others try, they will/can share their experience(s).
You willing to commit build a pair? So far I am getting ridiculed and laughed here. I am not going to spend the time taking pictures, writing it up so people can laugh more. I am not selling anything, just sharing experience, seems like people are too close minded.

Also read post 432 first, some situation, the cable might not make a difference. I don't want you to waste time and money to build one that will not help.

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one thing with any hobby is that people like to enjoy it. they throw what money they can at it to enjoy. enjoyment might come from pride in ownership, looks, sound, etc..

I dont see many discrediting some very nice systems on this forum. so lets not shoot our own hobby down. do car enthusiasts go to car forums and make fun of those fancy ignition wires?
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post #471 of 592 Old 02-18-2018, 05:20 PM
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Quote:
Originally Posted by alan0354 View Post
THD measured at 4ohm 65V peak to peak, that is 132W output power. About 0.001%@1KHz, [email protected] Gradually increase from 1KHz to 20KHz. That is about 0.0025%@10KHz or so.

The difference between me and the audiophile industry is I am trying to tell you to build a pair yourself for $30, they are trying to sell you a pair for hundreds of dollars. I am actually trying to debunk them using theory and experiment. I am not with them if you stop and think about it. So please don't put me with those companies.

Hell, you can't build a pair with Monster 12 gauge cable much cheaper than what I suggested!!! If this is snake oil, it's really really cheap snake oil.
1) 65vpp is 46vrms. so ((46 * 46) / 4) = 529 watts! or if 8 ohms 264 watts. How are you coming up with 132 watts?

2) 0.001% is pretty good at 1khz. But how about at 20hz? Getting good distortion figures in audio power amps down there is the hard part.

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post #472 of 592 Old 02-18-2018, 05:21 PM
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Originally Posted by imagic View Post
- Bingo. For me, success IS a thread that (potentially) requires heavy moderation because it creates a vigorous discussion and generates the traffic that goes with such discussion.

My forum threads are created as the "comments section" for homepage posts.



Huh? I'm Senior Editor of the site. I'm not a mod and I'm not an admin.

I am aware that these discussions get heated. When you have this many comments and participants, it's easy for a thread to go off topic, or for the discussion to get caught up in a sub-topic.

Any thread can go off topic. Predicting the long tail of thread like this is like predicting the path of a hurricane.

Fact: 13,000+ views and 460+ comments in under a week in this sleepy sub-forum = a good choice of subject matter.
Thank you Mark. Sorry for the wrong title. As you can tell I am not a fan of this type of thread no matter how "successful". If you have to remove a number of uncivil posts and redirect the conversation there is something wrong IMO. I agree that the Two Channel Forum is sleepy and draws a limited number of participants. Then again the entire site other than this forum is geared to AV solutions so it's not surprising.

On the positive side, there is a lot of good information in the thread even if it above the typical buyer's head.

May I also say that I very much appreciate this website and especially the work of the editors and moderators. I have been a moderator on a BMW forum for a number of years and was until recently a moderator on a major website for luxury watch fans for about 15 years.
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post #473 of 592 Old 02-18-2018, 05:28 PM
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Quote:
Originally Posted by Dark Matter View Post
Quote:
Originally Posted by golfster View Post
How could I have forgotten about this item. Be sure to read the customer comments. "made a bigger improvement in sound quality than the last $1000.00 interconnect cables I purchased"
http://www.machinadynamica.com/machina31.htm
I can't believe people actually purchased this stuff. Worse yet, that they claim to hear an actual difference before and after using the "equipment". I understand that confirmation and expectation biases can be powerful, but still. These comments defy logic and reasoning.
Of course they "hear" a difference. Whenever someone makes a change to a system, they pretty much always listen more intently than before. So they hear details they did not notice before, and thus there is an improvement. This is one of the fundamental reasons why snake oil sells so well.

This is why testing to deal with human bias is essential, or one ends up with anything and everything being believed to make a difference.


Edited to add:

Very likely, the rocks made exactly the same amount of audible difference as the $1000 cable made.

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post #474 of 592 Old 02-18-2018, 05:33 PM
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1) 65vpp is 46vrms. so ((46 * 46) / 4) = 529 watts! or if 8 ohms 264 watts. How are you coming up with 132 watts?

2) 0.001% is pretty good at 1khz. But how about at 20hz? Getting good distortion figures in audio power amps down there is the hard part.
65Vpp= 32.5Vpeak. Peak current is 32.5V/4ohm=8.125Apeak. P = (1/2) X Ipeak X Vpeak = 132W

In fact, I just tested at 20Hz, it's about 0.003%. A little higher, but it's ok. It's hard to measure at 20Hz, the 3rd harmonics is 60Hz that has a lot of power supply ripple embedded in it.

Yes, 20Hz is actually surprisingly harder. because of DC offset issue at the output, most amps have to have some sort of AC grounding scheme that actually make it a little worst at this low frequency. Most amps spec at 1KHz and 20KHz only, so I just follow.

How much you know about electronics, seems like you do know more and ask the right questions.

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post #475 of 592 Old 02-18-2018, 05:33 PM
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Enough of this pseudoscience nonsense.

You realize you'd need like 100uH of induction to even come close to being audible, right? Most generic stranded cable measures between 0.1 - 0.2 uH per foot. So maybe somewhere around 500-1000 feet the inductance will actually matter. If you're building amps, I'd imagine you have an LCR meter and a scope, this is trivial to measure the actual impact. Obviously you haven't, or you'd just post the measurements and test setup.
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post #476 of 592 Old 02-18-2018, 05:39 PM
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Originally Posted by Jack D Ripper View Post
Of course they "hear" a difference. Whenever someone makes a change to a system, they pretty much always listen more intently than before. So they hear details they did not notice before, and thus there is an improvement. This is one of the fundamental reasons why snake oil sells so well.

This is why testing to deal with human bias is essential, or one ends up with anything and everything being believed to make a difference.
I've certainly made a point of listening more intently after acquiring a new receiver, speakers, or changing sound cards/DACs on my PC. Fortunately, I don't believe I've ever fallen prey to biases, as I've only heard improvements in better sounding speakers, and one receiver that did sound a bit more detailed, but was very weak in power output, so it went back to the store. I remember buying a Denon receiver and not particularly paying attention, I noticed the flautist taking breaths between notes at the intro to "Ronin". I'd never heard it before so then of course I wanted to play it on my PC, the tv upstairs with a simple stereo, and then back on my original receiver after returning the Denon. Other than those moments of clarity, so to speak, I've never heard noticeable differences in new equipment. I began to wonder if maybe my hearing was more damaged than I originally thought, after serving in the military, and playing lots of loud rap music as a teen. But my hearing checks out, so I guess I'm largely immune to expectation bias. Being a huge skeptic also helps a bit, I think. If I have to hold my breath and strain my ears or eyes to notice a difference, it probably isn't there, or not to a point that's worth an upgrade.
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post #477 of 592 Old 02-18-2018, 05:39 PM
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You willing to commit build a pair? .
When I see detailed plans, I may.



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post #478 of 592 Old 02-18-2018, 05:40 PM
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Originally Posted by alan0354 View Post
65Vpp= 32.5Vpeak. Peak current is 32.5V/4ohm=8.125Apeak. P = (1/2) X Ipeak X Vpeak = 132W

In fact, I just tested at 20Hz, it's about 0.003%. A little higher, but it's ok. It's hard to measure at 20Hz, the 3rd harmonics is 60Hz that has a lot of power supply ripple embedded in it.
Your formula is wrong. You say 65vpp = 32.5 peak? Peak what?

First peak voltage is * 1.414. so (65vpp / 1.414) is 46 volts rms (OK, 45.968882).

Current? well 46 volts into 4 ohms is 11.5 amps! So 11.5 * 46 = 529 watts. There you have the same answer another way!

Vrms Squared over R is a standard power measurement.

You asked about my background in electronics?
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post #479 of 592 Old 02-18-2018, 05:46 PM
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I guess this conversation is going nowhere. I cannot do DBT, ...
How about measuring the frequency or each cables to a very high precision and compare the frequency response and differences in dB. JND is known for amplitude variations. Even an ASA Journal on it.
Fred Davis did an AES Journal paper comparing cables: inductance, capacitance effects and plotted them. Your cables are different and am sure you have the means to measure and plot. You could even include FR differences due to skin effect .
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post #480 of 592 Old 02-18-2018, 05:48 PM
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Enough of this pseudoscience nonsense.

You realize you'd need like 100uH of induction to even come close to being audible, right? Most generic stranded cable measures between 0.1 - 0.2 uH per foot. So maybe somewhere around 500-1000 feet the inductance will actually matter. If you're building amps, I'd imagine you have an LCR meter and a scope, this is trivial to measure the actual impact. Obviously you haven't, or you'd just post the measurements and test setup.
OK, lets look at 0.2uH/ft. 6ft long cable is 1.2uH. Let calculate the reactance at 20KHz. Z=jwL= j X 6.28 X 20,000Hz X 2EE-6H=0.15ohm.

Look at the equation of post 430 in the last page, plug into the formula for 4ohm speaker, You see that the j0.15ohm is not insignificant. If the load is non linear, distortion in voltage across the speaker is significant enough.

So please, before you put this whole thing down, please at least do the calculation like I did!!!

That's actually where multiple small wires in parallel have the HUGE advantage over one big wire. Inductance is almost the same regardless of the size of the wire. 4 16gauge wires parallel will give you 0.15ohm/4= 0.0375ohm of reactance. Huge advantage over one big wire.

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