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Old 23rd Feb 2023, 12:08 pm   #3001
mark_in_manc
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Default Re: The Audiophoolery Thread.

There's a 'silver' (that is, the bit of paper wrapped round it is silver-coloured) fuse option from the same people which is £4,200.

I reckon this works like an optimisation algorithm. You start at 20 quid (for a fuse! - surely no-one will go for it) and when (to your surprise) you sell a few, you double the price and try again. The clock-rate on the experiment is a bit slow - each iteration takes a while to put into the market and wait - but you'll get there in the end.

If I was writing the code, I think the cost function would be related to the sum total of all the money earned off all the price points - since one would imagine the £4k option might soak up nearly all income from the £2k option, but not perhaps from a £100 'entry-level' offering.

Then again, I think David pointed out that sales volumes would be likely very low indeed, so perhaps all stochastic-expectation bets are off and anything can happen. Maybe there's no upper bound at all and the company will (with a single sale) eclipse BP, Shell and Google combined!
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Old 23rd Feb 2023, 12:48 pm   #3002
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Default Re: The Audiophoolery Thread.

A secondary effect of the price is that unless one has blown, absolutely no-one is going to break one apart to see how it's made. There would simply be too much financial loss. No-one would discover if it was merely a re-marked cheap commodity fuse. Doing only a 13A value reduces the likelihood of one blowing and ensures serious destruction should one blow. This protects the trade secret.

There has, perhaps, been some careful product optimisation.

Real mithril endcaps, a Meissen china tube and a strand of silver from a unicorn's coat aren't cheap. A true entreprenoor will cut corners.

David
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Old 23rd Feb 2023, 4:34 pm   #3003
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Default Re: The Audiophoolery Thread.

Fuses have a resistance that is a strong function of the current drawn. This is a known and measurable effect when used as a protection device on power amplifier outputs. Putting such a fuse inside the feedback path gets around that problem. Of course in the event that it blows, the amplifier goes open loop. So you put a resistor in parallel with the fuse so if it blows, the amplifier still has enough feedback to be happy.

Now the way to remove all question of a mains fuse causing degradation in sound quality is to put it inside a feedback loop. Left as an exercise for the reader.

Craig
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Old 25th Feb 2023, 11:42 am   #3004
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Default Re: The Audiophoolery Thread.

Anyone for speaker cables

https://www.futureshop.co.uk/nordost...rminated-pair/
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Old 25th Feb 2023, 12:30 pm   #3005
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Default Re: The Audiophoolery Thread.

In the same way that fortune tellers and the like now have to stipulate that their services are for fun only, the makers of this kind of snake oil should also have to state that their claims are totally subjective and not scientifically proven. Perhaps that would be unworkable, but maybe not if throughout the audio world any claims had to be backed up with specifications that proved them in advertising material, if not then my just mentioned caveat would have to be added. Then again, if people with deep pockets are stupid enough to buy them... It still irks me that the people making these products know darn well that using mumbo jumbo, weasel words they are pedalling expensive, totally unproven equipment, but are happy to rip people off to line their own pockets. Annoying and depressing in equal terms.
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Old 25th Feb 2023, 12:59 pm   #3006
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Default Re: The Audiophoolery Thread.

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Originally Posted by stevehertz View Post
In the same way that fortune tellers and the like now have to stipulate that their services are for fun only, the makers of this kind of snake oil should also have to state that their claims are totally subjective and not scientifically proven.
Surely you're not questioning the value of the Nordost speaker cable's 98% velocity of propagation!?

Alan
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Old 25th Feb 2023, 1:35 pm   #3007
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Default Re: The Audiophoolery Thread.

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Quote:
Originally Posted by stevehertz View Post
In the same way that fortune tellers and the like now have to stipulate that their services are for fun only, the makers of this kind of snake oil should also have to state that their claims are totally subjective and not scientifically proven.
Surely you're not questioning the value of the Nordost speaker cable's 98% velocity of propagation!?

Alan
Well, sounds like you're not!
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Old 25th Feb 2023, 2:47 pm   #3008
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Default Re: The Audiophoolery Thread.

Gosh. That speaker lead makes the £2200 mains lead threaded through a block of wood look positively cheap.

https://www.futureshop.co.uk/entreq-...kaAqboEALw_wcB
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Old 25th Feb 2023, 5:03 pm   #3009
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Default Re: The Audiophoolery Thread.

What these extreme esoteric cable manufacturers miss, or perhaps don't and just keep quiet about it, is that in every loudspeaker voice coil there are many tens of meters of bog standard copper winding wire, with high temperature insulation.

Shock horror!

Craig
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Old 25th Feb 2023, 5:20 pm   #3010
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Default Re: The Audiophoolery Thread.

No difference really between the Speaker cable and the fuse suppliers, the latter ignore the hundreds of meters of cable, circuit breakers and fuses that lead up to the 13A sockets.

Ian
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Old 25th Feb 2023, 5:29 pm   #3011
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Default Re: The Audiophoolery Thread.

What you're missing Craig is that electrons behave completely differently when they're coiled up inside thin copper wire sitting next to a magnet.

One thing I don't understand is why they don't seem to charge extra for 96 hour VIDAR 2 Premium Burn-In (almost makes them a bargain). Also the cables are only available in the UK. Are our laws on misrepresentation more lax than the rest of the world or is it a patent infringement issue?!

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Old 25th Feb 2023, 5:37 pm   #3012
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Default Re: The Audiophoolery Thread.

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No difference really between the Speaker cable and the fuse suppliers, the latter ignore the hundreds of meters of cable, circuit breakers and fuses that lead up to the 13A sockets.

Ian
Not to mention the hundreds of metres of bog standard copper cable contained in recording desks and processing equipment that carry and ha, 'spoil' the signal before it is recorded or transmitted. Actually there's a case for a piece of equipment, a unit that can 'cleanse' and 'correct' signals that have previously passed through poor quality cable. Don't tell me, it's already been done?
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Old 25th Feb 2023, 5:50 pm   #3013
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Default Re: The Audiophoolery Thread.

I looked at what was in the Vidar from pictures on the web. Basically is a pseudo random noise generator. This is a perfectly standard technology using tapped feedback shift registers - I used it back in the early 80's to add controlled noise to a video channel. If you design these right, the repeat pattern is measured in tens of years at typical clock rates.

The original Vidar used I think opamps to drive the cable.

The Vidar 2 has digital readout of something or other, and paralleled transistors to drive the cable. But the core noise generator is I think the same.

There is very little in there apart from that.

You cannot buy one of course. They are only sold (or rented?) to Nordost dealers.

Got to keep the mystery alive!

Craig
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Old 25th Feb 2023, 6:44 pm   #3014
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Default Re: The Audiophoolery Thread.

But that's digital noise, not good, simple analogue noise. It'll be full of quantisation artefacts from all that modulo-2 arithmetic.

It's all laid bare in "Shift register sequences" by Solomon W Golomb (pronounced in a way that would amuse J R R Tolkien)

But rather than lust after the unavailable Nordost item, fully adjustable PRBS noise sources have been available since about 1970

https://usermanual.wiki/Document/A3722A.3493673788.pdf

and can be picked up fairly cheaply on the surplus market. There is also a matching Correlator and an accessory spectrum display so you can monitor progress as you cook your cables. Heaven only knows what criterion you use to tell when they're 'done'.

Real mathematics, real science, long before the loony fringe hitched a ride.

Those things were designed by the UK arm of HP, and I still know some of the people responsible.

David
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Old 25th Feb 2023, 9:58 pm   #3015
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Default Re: The Audiophoolery Thread.

Quote:
Originally Posted by ajgriff View Post
What you're missing Craig is that electrons behave completely differently when they're coiled up inside thin copper wire sitting next to a magnet.

One thing I don't understand is why they don't seem to charge extra for 96 hour VIDAR 2 Premium Burn-In (almost makes them a bargain). Also the cables are only available in the UK. Are our laws on misrepresentation more lax than the rest of the world or is it a patent infringement issue?!

Alan
One UK cable vendor got into hot water a few years back for making certain claims

(I think this was discussed about 30 pages back in this thread - just in case anyone didn't see it)
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Old 25th Feb 2023, 10:19 pm   #3016
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Default Re: The Audiophoolery Thread.

I've met Russ Andrews. I just wish I could time-machine a message back to me all those years ago just before going to his shop, to have a candid camera and microphone for the impromptu event.

His claims are no more unsupportable than pretty much all of the audiophile market. That isn't to get him off the hook, it's to put the whole industry on the hook. Stick to supportable claims.

David
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Old 25th Feb 2023, 11:44 pm   #3017
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Default Re: The Audiophoolery Thread.

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Originally Posted by Craig Sawyers View Post
What these extreme esoteric cable manufacturers miss, or perhaps don't and just keep quiet about it, is that in every loudspeaker voice coil there are many tens of meters of bog standard copper winding wire, with high temperature insulation.

Shock horror!

Craig
Even worse - in tweeters, where low mass is required, they can be aluminium (and sometimes copper coated aluminium).

What's more, wire is often flattened prior to winding (gets more turns in a given length) - I wonder what they'd make of that? Does it make the music sound less rounded, or will the frequency response be more flat?
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Old 26th Feb 2023, 12:11 am   #3018
Craig Sawyers
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Default Re: The Audiophoolery Thread.

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I've met Russ Andrews. I just wish I could time-machine a message back to me all those years ago just before going to his shop, to have a candid camera and microphone for the impromptu event.

His claims are no more unsupportable than pretty much all of the audiophile market. That isn't to get him off the hook, it's to put the whole industry on the hook. Stick to supportable claims.

David
Time to fess up again. The SD mains cables (for Sawyers Disc) and the Evolution range are both my designs.

Hides under the chair.

Craig
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Old 26th Feb 2023, 8:53 am   #3019
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Default Re: The Audiophoolery Thread.

You're safe. You're protected by a lot of mileage

My real concern is that audiophile products are marketed mostly to people without any scientific/engineering background which would allow them to make rational judgements on what is offered. People's impressions of what something sounds like are, well, impressionable and this seems to be exploited.

Some of these things are quite well made, but often looking at what's involved and then seeing the prices leaves me wondering whether a vendor merely shares the delusions of his target market or is on the scam. As the vendor is sure to know the actual costs, then it would suggest that in plenty of cases scam outweighs delusion.

I've put quite a number of products through EMC ingress/egress testing to various countries' EMC regs, both mains and DC (for aviation) power. You learn what works and you are under pressure to make the anti-emc measures live entirely within the product. Relying on a special mains cable would have been grounds for termination (pun deliberate) if there was any alternative.

Some military stuff had screening braid on their mains cables, but that was associated with appropriate connectors like Plessey Mk4 and they had coontrol over the power distribution wiring. Having 2m of shielded cable to then normal unscreened, untwisted house wiring has limitations.

So I prefer to go with ferrite chokes, common and differential mode, X and Y rated capacitors. This can be made to work well, to pass all required tests and is remarkably affordable compared to the audiophile prices.

Some of the things I did were classed as EMC measuring receivers, and they are subject to rather fierce requirements.

HP made a goof in this area. Before EMC regs got harmonised across Europe, Germany was the leader in the EMC regulation field. Hit their targets and all the others were less demanding. Germany had two EMC laws, the normal one and the "Measuring receiver law" The (translated) wording made it look like any box that had a signal input connector and produced measurement results on the applied signal was a "Measuring receiver"

oo-er! It looked like frequency counters, telephone line testers, oscilloscopes all were measuring receivers and needed to meet the tougher pass marks.

It turned out that the measuring receiver requirements were meant for the receivers needed to perform EMC tests! I only found out quite a bit later when designing a real EMC measuring receiver system for the German regulatory authorities. They were helpless with laughter.

So we overdid it on a number of boxes, but we learned a lot in doing it, and our EMC test facilities were finely honed in the process.

David
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Old 26th Feb 2023, 10:39 am   #3020
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Default Re: The Audiophoolery Thread.

I think that there are major issue with the vast majority of esoteric mains cables first is that they are rarely, if ever, compliance tested for CE and UL certification.

The other is that they are rarely if ever supported by measurement. Or even simulation. (my designs both are. Both simulated and measured)

I take your point David regarding making anti-emc measures within the product. Would it were the same in domestic audio equipment - at any price point. It is of course straightforward to do so. Since Adam was a lad the instrumentation community has adopted methods to keep garbage out of equipment, as have standards labs (NPL,PTB etc). These often use triple box-shielded mains transformers, within nested shielded enclosures. Effective primary/secondary capacitance is sub-pF.

Of course such carefully designed and built transformers are (very) expensive and need real design skill to apply. So a bog standard transformer with open wiring is usually what is used.

The Plessey MkIV, used by Racal and AVO to name two, was never really intended for mains power wiring. Although the regular 3 pin type is nominally rated at 350V (so 240V ac) and 2.5A, that assumes very careful assembly (the solder buckets are ~5mm spacing).

And the required colours are red to pin A, blue to pin B and green to pin C (so not any recognized mains colours). Screening braid to the shell. And although the hipot withstand voltage with the pin spacing is around 3kV, that assumes high levels of cleanliness between the pins.

Because of the relative rarity of the cable connectors and high price, many owners of equipment using these connectors have swapped them for IEC, or soldered in a mains tail and gland with a cable IEC.

Craig
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