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Old 16th Oct 2017, 10:16 am   #201
Craig Sawyers
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

And just when you thought that shielded coax was the panacea to interference - Shield Induced Current Noise (SICN) from the professional audio company RANE:

http://www.rane.com/pdf/ranenotes/SC...uced_Noise.pdf

These are hard bitten guys - they don't believe in cables sounding different per se - they actually measure things. Their "Rane Notes" are well worth a peruse http://www.rane.com/library.html

Craig
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Old 16th Oct 2017, 10:18 am   #202
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

The amp in the CD player is built to drive speakers with a potential divider for the head phone output. the spec of the amplifier gives a distortion figure with plenty of "0"s in front for that distortion figure. I bet that is for the headphone output with little load on the output stage.
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Old 16th Oct 2017, 1:52 pm   #203
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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Originally Posted by Craig Sawyers
The background is that cycling to liquid nitrogen results in stress relieving. So at least the plausibility argument is that doing the same thing with a valve changes in some way its characteristics, at least audibly.
It is just possible that cryo treatment could modify valve microphonics. It won't alter distortion etc.

Quote:
OK - I hear you say "This is digital - it is 0's and 1's". Well it might be at one point, but I'd invite you to look at an eye diagram for the analogue output from the photodiodes in a CD mechanism. A CD mechanism is analogue through and through. Focus, tracking and data.
Error correction means that the data entering the DAC is perfect almost all of the time.
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Old 16th Oct 2017, 2:01 pm   #204
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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Quote:
OK - I hear you say "This is digital - it is 0's and 1's". Well it might be at one point, but I'd invite you to look at an eye diagram for the analogue output from the photodiodes in a CD mechanism. A CD mechanism is analogue through and through. Focus, tracking and data.
Error correction means that the data entering the DAC is perfect almost all of the time.
All the right bits, necessarily in the right order, but with timing jitter. That's analogue, and measurable, and has a mathematically demonstrable effect on the audio output - a sort of phase modulation, effectively. It'a also an issue for self-clocking digital audio interfaces like SPDIF, either electrical or optical. Of course, buffering the data and re-clocking it from a low-jitter source fixes the problem, but very few DACs bother with that.

Whether we can hear the effect or not is another matter.

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Old 16th Oct 2017, 2:06 pm   #205
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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Originally Posted by Craig Sawyers
And just when you thought that shielded coax was the panacea to interference - Shield Induced Current Noise (SICN) from the professional audio company RANE:
That note is not about coax, but shielded twisted pair. The effect cannot occur with coax, because by definition there cannot be a difference in magnetic coupling between the shield and one inner conductor - for that you need at least two inner conductors.
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Old 16th Oct 2017, 2:12 pm   #206
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Where were you working on high power CO2 lasers? A Culham studenship?
Not CO2, but KrF which is a bit more challenging. I did my DPhil at the Clarendon Lab in Oxford. The people who taught me about 316 machining were the workshop guys there, several of whom remembered Martin Wood (although maybe not the actual technician who did my electrode sets for me). So I'm a bit surprised the knowledge had to be re-learned at Oxford Instruments.

A very good friend of mine did have a one year placement with the Culham CO2 team though.

Cheers,

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Old 16th Oct 2017, 2:14 pm   #207
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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All the right bits, necessarily in the right order, but with timing jitter. That's analogue, and measurable, and has a mathematically demonstrable effect on the audio output - a sort of phase modulation, effectively. It'a also an issue for self-clocking digital audio interfaces like SPDIF, either electrical or optical. Of course, buffering the data and re-clocking it from a low-jitter source fixes the problem, but very few DACs bother with that.
Timing jitter comes from clocks (inside CD players) and cables (to external DACs). The optical drive should not affect this, unless the CD player has quite bad PSU and power distribution design. Buffering and reclocking is an inherent aspect of the data de-interleaving and error correction. Hence what goes to the DAC is locked to a crystal clock. High frequency jitter can be added by external SPDIF connections, but the DAC will then include a PLL to remove this.

Jitter can be a problem, but it is not as big a problem as some people fear. Strangely, the popular 'fix' (a bolted-on oscillator 'upgrade') will often make things worse due to interfacing problems such as ground-bounce.
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Old 16th Oct 2017, 5:08 pm   #208
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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Error correction means that the data entering the DAC is perfect almost all of the time.
CIRC error correction will deal with with significant random and burst errors. But it finds it difficult to deal with systematic errors that tend to cause timing skews as a result of mechanical resonances, or any effect that tends to impact on the raw analogue data stream.

Prof Malcolm Hawkesford at the University of Essex has a good demonstration in which he ac couples the servo signals on a CD player, amplifies them, and demonstrates that they have a distorted version of the analogue audio stream impressed on them. Now this is quite a while ago, and it escapes me whether this was as a result of an electrical coupling mechanism, or an acoustic phenomenon because of the acoustic environment from loudspeakers.

I'll try and find out and report back if I find the information.
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Old 16th Oct 2017, 5:23 pm   #209
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Where were you working on high power CO2 lasers? A Culham studenship?
Not CO2, but KrF which is a bit more challenging. I did my DPhil at the Clarendon Lab in Oxford. The people who taught me about 316 machining were the workshop guys there, several of whom remembered Martin Wood (although maybe not the actual technician who did my electrode sets for me). So I'm a bit surprised the knowledge had to be re-learned at Oxford Instruments.

A very good friend of mine did have a one year placement with the Culham CO2 team though.

Cheers,

GJ
KRF is indeed a challenge. Even if clean it tends to pit the electrodes. There are interesting stories about the supersonic flow CO2 TEA laser at Culham - 30kW of light caused some safety headaches.....

Regarding Martin - well he was essentially out the equation when I was there in the early 90's (very much the elder statesman), although I knew him reasonably well. But the detailed information gets diffused and needs to be relearned. Probably periodically.

Of course since I left the 100-strong highly skilled mechanical workforce in the Research Instruments Division has been disbanded, and all the mechanics is subcontracted, with coil winding as far flung as China.

There *might* be some core skills left, but I've been out of there for 20-odd years now, so the current state of the ship is anybody's guess.

My research degree was in Nd:YAG, which was quite a beast in its own right. Some light bedtime reading https://eprints.soton.ac.uk/393635/1/82032212.pdf .

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Old 16th Oct 2017, 6:30 pm   #210
G8HQP Dave
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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CIRC error correction will deal with with significant random and burst errors. But it finds it difficult to deal with systematic errors that tend to cause timing skews as a result of mechanical resonances, or any effect that tends to impact on the raw analogue data stream.
As I said, the data going to the DAC has been clocked by a crystal. Uncorrectable errors are rare. Hence we have perfect data at the right time.

Quote:
Prof Malcolm Hawkesford at the University of Essex has a good demonstration in which he ac couples the servo signals on a CD player, amplifies them, and demonstrates that they have a distorted version of the analogue audio stream impressed on them. Now this is quite a while ago, and it escapes me whether this was as a result of an electrical coupling mechanism, or an acoustic phenomenon because of the acoustic environment from loudspeakers.
I treat with suitable caution any claims made by Hawkesford, and any deductions made from those claims.
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Old 16th Oct 2017, 7:05 pm   #211
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

Oh dear.
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Old 16th Oct 2017, 8:57 pm   #212
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

I bought one of those green pens for CDs, but instead of spending hours painting it around the edge of every CD I own, I used it to paint one huge thick ring right around my whole CD player!

The difference is astounding!

I'm smart!

David
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Old 16th Oct 2017, 9:33 pm   #213
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

I am listening to Youtube on a pair of USB headphones to Slade Yes, Led Zeppelin. ELP amonst others its my 61st Birthday.

You can argue to the cow come home guess What I do not care.

Audipholes are well named.

You can have the best system money can buy yet why is it it you can can enjoy a local band at the pub with shocking acoustics.

It does not mean I dont have a system capable of respectable reproduction but its just that, others will have far better and spent more or less.

Time to stop giving the Phools any oxygen of publicity on this forum just ignor them.

Let them get incresingly anal of their own forums

Gotta Go TRex Get it on is playing.

Cheers

Mike T
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Old 16th Oct 2017, 10:16 pm   #214
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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I bought one of those green pens for CDs, but instead of spending hours painting it around the edge of every CD I own, I used it to paint one huge thick ring right around my whole CD player!

The difference is astounding!

I'm smart!

David
I must try that David
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Old 16th Oct 2017, 11:26 pm   #215
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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You're clearly confident in that position.

Cheers,

GJ
Since you are confident in your position too, that is, it is basically ok to tell "Audiofibs" if it appears to be mutually beneficial for customers and sales, I thought I would put this question to a few of my colleagues to see what the general opinion might be. The question was posed in the form:

" Is it wrong for a person with scientific expertise, such as an Engineer, to advise anyone with information that they know is untrue and not based in science, provided there is a mutual benefit to both, and if there is no third party harm ?"

The general response was that on your side of the argument was, on the face of it, it appears harmless. However the Engineer who does this dishonors both themselves and their entire belief in science. In short, it is a dishonorable thing to do.

In this day and age there seems to be less importance placed on this quality, but it was and still is a severe no-no to behave dishonorably in Japan.
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Old 17th Oct 2017, 7:16 am   #216
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

Hi,

Really, come on guys some of the posts are now getting rather hurtful for anyone working in the Audio industry and as I said there are some good honest engineers in the audio industry.

I really donít want to have to get my coat as I said in post 183.

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Old 17th Oct 2017, 9:09 am   #217
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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Since you are confident in your position too, that is, it is basically ok to tell "Audiofibs" if it appears to be mutually beneficial for customers and sales ...
That's not my position. I tried to make my position clear back in post #73 when I said

Personally I draw the line at misleading people. Not only would it leave a bad taste in my mouth but my professional body (the Institute of Physics) could, in principle at least, chuck me out if I were caught bringing the subject into disrepute . But I hesitate to go out of my way to attack their beliefs. Some of them seem genuinely happy as a result of them and who am I to ruin that ...


However I am aware that hi-fi customers are pursuing a hard-to-reach goal and are happy (I genuinely think that that is the correct word) to pay for things which help them get there.

I was interested in your comments on the Japanese view of this. Would they be compatible with the Kondo philosophy http://www.audionote.co.jp/en/philosophy.html or Leben's use of distinctive capacitors http://lebenhifi.com/products/cs300xs.html or Shindo's attachment to vintage components http://www.coolhunting.com/tech/shindo-laboratories or Luxman's belief in the "elegant tonal quality that is unique to the performance of the TA-300B, a direct heated triode" http://www.luxman.com/product.php?pid=56 ?

Cheers,

GJ
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Old 17th Oct 2017, 9:16 am   #218
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

There are good guys in the audio industry.

I know one very good engineer who was involved in a famous firm whose products were adulated beyond reason by pundits in the hifi press, yet they were the result of scientific, rational, good, engineering. The chief honcho of that firm was more than a bit of a showman and inclined to say things planned to shock. The press loved him. It must have been difficult deciding how to design things and what not to say so that the 'glamour' wasn't blown away inadvertently. It was certainly very profitable.

The problem with the audio industry as a whole (and plenty of other industries as well) is that those who haven't a clue make a lot more noise than the quiet, considerate folk. But it is the quiet ones who are most valuable.

david
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Old 17th Oct 2017, 10:38 am   #219
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

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The problem with the audio industry as a whole (and plenty of other industries as well) is that those who haven't a clue make a lot more noise than the quiet, considerate folk. But it is the quiet ones who are most valuable.

david
I generally agree. But where would you say *Peter Walker stands on this? he was in may ways a great trail blazer and innovator, but he also made some outrageous statements about hifi equipment that most people think were quite stupid and factually wrong. I suppose that was the showman in him, he was a bit of both in my opinion, a rare breed.

* This is an edit, I originally said Richard Walker! (He was the great angler..)
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Old 17th Oct 2017, 10:44 am   #220
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Default Re: Audiophoolery. 'Cable Break In' - I never knew that!

Peter Walker? Ross Walker? Not sure who Richard Walker is/was - google was no help on that name.
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