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Old 25th Dec 2020, 9:29 am   #2061
Craig Sawyers
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Default Re: The Audiophoolery Thread.

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Originally Posted by GrimJosef View Post
Depends what you call 'far' infrared. All room temperature objects (say 300K) radiate infrared, and if their spectrum is anything like a black-body then the wavelength of peak radiation is around 10 micrometres. As the temperature goes up, the wavelength comes down in inverse proportion. So the surface of the sun, at close to 6000K, has a spectral peak in the yellow-green, close to 0.5 micrometres. The spectrum is very broad of course, so even the sun emits plenty of infrared.

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GJ
Yes that is true. But the radiated energy depends on the emissivity of the surface. Which means that the object has to be black in the relevant region of the spectrum.

However since any thermal radiator will only radiate if there is a difference in temperature between the radiator and the environment (Second laws of thermodynamics "When two initially isolated systems in separate but nearby regions of space, each in thermodynamic equilibrium with itself but not necessarily with each other, are then allowed to interact, they will eventually reach a mutual thermodynamic equilibrium"), what Furutech are actually saying is that their mains connector initially gets hotter than the room in which it is located.

Which means that what they are saying is that their exceptionally expensive connector has a significant contact resistance, is consequently is pretty useless.
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Old 25th Dec 2020, 11:54 am   #2062
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Default Re: The Audiophoolery Thread.

Any conductor will have resistance at 300k* and therefore when carrying current get warmer, not a lot, but warmer than ambient. Their connector doesn't have to have a silly amount of resistance for the somewhat daft claim to be true.

*as of 25/12/2020 anyway!
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Old 25th Dec 2020, 12:15 pm   #2063
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Default Re: The Audiophoolery Thread.

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However since any thermal radiator will only radiate if there is a difference in temperature between the radiator and the environment (Second laws of thermodynamics .
Effectively so, but it's clearer to think that an object at non-zero temperature always radiates, but if it's in an environment at the same temperature, then everything else that constitutes that environment radiates precisely the same amount back at it. This allows analysis with linear equations and no 'if' clause.

Thermal radiation doesn't stop at low frequencies, even for objects smaller than a wavelength, it just becomes accessible by electrical connection and flattens off to kT Watts/Hz. With connectors in the Ohm region and a few degrees above 300K, I'm certain that the high-end people would be able to hear it, if they knew about it

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Old 25th Dec 2020, 12:47 pm   #2064
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Default Re: The Audiophoolery Thread.

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It goes all the way back to "XXXXXX washes whiter".

The advertising standards people accept that unsupportable claims and superlatives will get used. They assume that the public will not believe them. Advertisers get into trouble when they make statements which can be objectively proven or disproven.
Folks here might enjoy a quick anecdote about this, concerning toothpaste which (allegedly) got your teeth really clean and fizzed while it did it. I used to work at a place which had an anechoic room with an acoustic noise floor below -20dB SPL across most of the audible band, and some 1" B&K mics which didn't have much of a bandwidth but which were sensitive enough to measure this noise floor. We once had a small job to record the _real_ sound of fizzing toothpaste, since apparently unless the _real_ (but very amplified!) sound was used in the advert, the ASA people would have things to say. Cue a few research students foaming at the mouth in the test facilities in conditions of more or less total silence

(The ASA differ in their understanding of gain, from strict members of a religious community near here who wanted me to look at speech intelligibility in their gathering, but were averse to electronic amplification which in their view meant that the utterances of the leader were no longer, errr, kosher. I toyed for a short while with a frontal assault on this idea using an analyser which could display cross-correlation, but in the end withdrew from the enquiry as gracefully as I could manage )
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Old 25th Dec 2020, 1:13 pm   #2065
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Default Re: The Audiophoolery Thread.

My dad who became a teacher after 22 years in the RAF wanted a tape recording of an apple "crunch" for a class quiz. He was oblivious of me and my brother nearly choking on apples just demanding "more crunch, more crunch".
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Old 16th Jan 2021, 8:02 am   #2066
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Default Re: The Audiophoolery Thread.

Thanks to some superb posts by David here https://www.vintage-radio.net/forum/...d.php?t=175279 on the real technical problems with esoteric speaker cable and amplifier stability, I thought it might be interesting to mention that there is around 50 metres of bog standard winding wire in the loudspeaker drivers, that the resistance of that wire changes with the power dissipated (with a time constant of many seconds), and that they have about 1% harmonic distortion.

But those fact does not sell speaker cable, naturally.

Craig
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Old 10th Feb 2021, 2:13 pm   #2067
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Default Re: The Audiophoolery Thread.

https://www.youtube.com/watch?v=tKan...ature=emb_logo

I am in the process of heating up the rework tools so that I can replace all of those pesky NE5532s with this gem. It's a bargain at 80x the price (does it have 80 times the distortion?)
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Old 25th Feb 2021, 8:54 pm   #2068
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Default New digital

I spotted this today

https://www.futureshop.co.uk/telluri...o-type-b-cable


Does this mean that everything I learned about digital electronics at University was wrong?
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Old 25th Feb 2021, 9:08 pm   #2069
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Default Re: New digital

It's just more audiophoolery. Some people think that more expensive means better. If they want to spend nearly 1k on a 1 USB cable then that's their privilege.
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Old 25th Feb 2021, 9:22 pm   #2070
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Default Re: The Audiophoolery Thread.

Ironic that Tellurium is lodged in our memories as being able to create halitosis effects in very small doses. Someone's having a snigger as they go to the bank!
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Old 26th Feb 2021, 2:58 am   #2071
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Default Re: The Audiophoolery Thread.

Bet more money and effort went into developing the name and marketing than into the product.

It implies that the noughts it tranansports have a seductive inky, almost velvety blackness, while the ones passing through it have a shining bell-like silvery clarity.

So it ought to sound good. Your ones will be more one-ish and your zeroes more nothingy.

Of course someone will explain that your error correction stuff will have to work less hard and this will save you the sonic terrors of your power supply working its guts out to keep up with the error corrector with lesser (say only 1000) cables.

Come back Boole, all is forgiven!

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Old 26th Feb 2021, 10:31 am   #2072
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Default Re: The Audiophoolery Thread.

I see your cheapo Tellurium and raise you a Nordost Valhalla https://www.futureshop.co.uk/nordost...pe-b-usb-cable

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Old 26th Feb 2021, 10:47 am   #2073
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Default Re: The Audiophoolery Thread.

I see that the Nordost Valhalla 6m USB cable with DeoxIT Gold G-Series contact enhancer and burnt in for 96 hours is a snip at 8,783. Got my last Type A to B USB cable for 50p at a boot sale. I'm clearly viewing life in the wrong way.

Alan
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Old 26th Feb 2021, 10:51 am   #2074
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Default Re: The Audiophoolery Thread.

Oh there is so much bull:

"If the light source were a coherent laser, firing into a vacuum, all the light would stay straight". No, even if were single TEM00 transverse mode it would propagate as a Gaussian beam with a half divergence angle of lambda/pi x w0 where w0 is the 1/e^2 waist radius. Typically a divergence full angle of a milliradian, so at 10 metres a 1mm waist diameter visible beam will have expanded to 1cm.

Of course this phenomenon is not limited to light - any freely propagating electromagnetic wave will behave similarly, whether it is microwaves or X-rays

More optical BS from https://www.futureshop.co.uk/audioqu...-optical-cable

Craig

Last edited by Craig Sawyers; 26th Feb 2021 at 10:57 am.
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Old 26th Feb 2021, 10:52 am   #2075
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Default Re: The Audiophoolery Thread.

It's difficult to imagine why anybody would believe that any of these digital interface cables would make the slightest difference to anything. Presumably the cable itself is just bought in from suppliers on a big reel and fitted with fancy plugs. I guess these things are bought by very wealthy people, for whom cost simply isn't a factor in their purchasing decisions, and they just think they're buying 'the best'.
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Old 26th Feb 2021, 11:08 am   #2076
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Default Re: The Audiophoolery Thread.

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It's difficult to imagine why anybody would believe that any of these digital interface cables would make the slightest difference to anything. ......... I guess these things are bought by very wealthy people, for whom cost simply isn't a factor in their purchasing decisions, and they just think they're buying 'the best'.
Well, anyone who doesn't understand the basics of electronics and has loads of money. They're the victims and seemingly, there's plenty of them. Or at least, enough to keep the charlatans in business. You don't have sell much stuff at 1000% mark up to make a good living.

There really ought to be legislation to stop this kind of thing, it's nothing but legalised misselling. Even fortune tellers now have to state that their 'work' is for fun only. There should be a similar rider on all hifi equipment - suggestions? Something that states that product technical specifications are fact and indeed challengeable, but any other claims may be considered to be purely subjective and not based on scientific proof whatsoever.
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Old 26th Feb 2021, 11:13 am   #2077
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Default Re: The Audiophoolery Thread.

Sad In a way that people believe this tripe common sense has no place with them .
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Old 26th Feb 2021, 11:37 am   #2078
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Sad In a way that people believe this tripe common sense has no place with them .
People have a habit of believing what they read in print. If the eminent scientist next door told them different, they wouldn't believe him.
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Old 26th Feb 2021, 12:24 pm   #2079
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Default Re: The Audiophoolery Thread.

Wouldn't be surprised if it is just a custom printed cable from the likes of sommer/van damme/mogami Etc. or just a custom cover, no one who buys this junk is going to cut it open to see the innards are they?

I reckon part of the issue is that the devices that these cables are sold for are probably designed in such a way that these products do make a difference.

I remember one of the SOS employees (who is also ex. BBC) on the SOS forums saying that he look at one piece of esoteric audio equipment to find that yes it did need these special cables but only because of the rubbish design that wouldn't be allowed/tolerated on truly professional equipment, and do you know what I trust that mans opinion immeasurably more than that of an "audiophile".
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Old 26th Feb 2021, 12:38 pm   #2080
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Default Re: The Audiophoolery Thread.

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Originally Posted by paulsherwin View Post
It's difficult to imagine why anybody would believe that any of these digital interface cables would make the slightest difference to anything. Presumably the cable itself is just bought in from suppliers on a big reel and fitted with fancy plugs. I guess these things are bought by very wealthy people, for whom cost simply isn't a factor in their purchasing decisions, and they just think they're buying 'the best'.
Surely this is just an excellent way of redistributing wealth!
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