Naked Science Forum
Non Life Sciences => Technology => Topic started by: Sprool on 12/01/2012 13:27:33
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I'd be interested in a reasoned scientific debate that justifies the incredible cost of these high end mains cables for hifi. Soaring to £1999/m for top of the range, it is supposed to give massively improved acoustic response by 'cleaning up' the mains feed to your amp.
http://www.cheshireaudio.co.uk/acatalog/copy_of_Nordost.html
http://www.nordost.com/93/blue-heaven-power-cord
I suspect a lot of very expensive snake oil here, but is there a proper reason why these leads, by reducing any ac noise from all that filthy mains electricity entering your house ring mains via the grid's dirty old exterior cables, can significantly improve the sound of your Snow patrol CD whirring away in your Amstrad?
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I rather suspect that this is a con, but am sure that there will be those foolish enough to buy them.
I have yet to hear any interference on my hi-fi caused by 'dirty' mains feed. Even if such a thing exists, I'm sure that there is a far greater chance of unwanted background noise coming through the walls and windows of my lounge spoiling my enjoyment of my favourite music, or even the sound of my own breathing, the squeak of my sofa as my chest moves during breathing or a spider farting in its web.
I've heard some old tosh in my life, this is certainly up in the top ten.
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£1999/m
They're 'aving a giraffe.
A twisted pair (https://en.wikipedia.org/wiki/Twisted_pair) wouldn't clean noise present at the mains socket, it would reduce the noise picked up by induction from the environment between the wall socket and the hi-fi, which would be a miniscule fraction (<1%) of the voltage the cable is carrying, which would be filtered out by the PSU (https://en.wikipedia.org/wiki/Rectifier#Rectifier_output_smoothing) on the Hi-Fi anyway.
Twisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of cancelling out electromagnetic interference (EMI) from external sources
https://en.wikipedia.org/wiki/Twisted_pair (https://en.wikipedia.org/wiki/Twisted_pair)
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Even cheap amplifiers have basic circuitry inside (a few tens of pence component cost) to smooth out peaks and farts in AC supply.
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The first two cords seem to have NEMA 5-15 plugs, standard in the USA. Do they work in the UK where these are apparently being sold?
I'm also dubious... You have standard unshielded wires from the power substation to the local transformer, and from the transformer to your house and throughout the house.
Then, suddenly 6 feet of shielded wire is supposed to make a world of difference?
This is the closest thing to your audio equipment, so if your equipment is susceptible to 50/60 HZ noise, the shielded wires may help a little, but it still ignores all the unshielded wire everywhere else.
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There's some special science about the world class speaker cables as well, with twisted minofilament insultor wrapped round the conductor before enclosing in a sheath - this extra air space provides a clearer signal current path since it is in less contact with the insulator. Do you think by rubbing up against the surface of an insulator, the signal quality might become somehow retarded, slowed down or lost?
Nordost winds a thin strand of ultra-pure FEP Mono-filament in a precisely spaced helical coil around each conductor – and then extrudes an FEP jacket over that strand. Using the Monofilament as a “stand-off”, the FEP jacket never touches the conductor. Only the FEP strand makes contact, achieving an 80% air gap, while maintaining perfect flexibility and superb mechanical damping: a one-two punch that no other brand can offer!
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I remain unconvinced - I am equally sceptical each way - about the benefits/ripoffs of high end audio interconnects. i can tell you that in a blind test about 20 years ago my girlfriend and I could hear the difference between good quality interconnects and those provided with a cd seperate (and yes we were all science (ish) students and it was a pretty good double blinded test). I have subsequently tried to hear the difference between good interconnects and stupidly expensive and cannot tell any difference. With a top end system one can hear the difference when an optional and isolated power feed is connected - however I have never tried this properly blinded, and even though one can hear a difference that is not necessarily good.
On the reductionist postion that argues that we cannot possibly hear the difference. I remember when CDs came in and reading eminent people foretelling the imminent collapse of vinyl because of the gulf in quality; now (with top end equipment) it is acknowledged there is a gap in performance - but that it is vinyl that is in the lead. Human senses continue to confound those who try to limit them and technology is continually trying to catch up.
As Graham mentioned (I think i was Graham- otherwise apologies) in a similar post many moons ago - as we get older we lose our aural acuity; those who can afford good systems can no longer discern the difference, and those with young enough ears to still hear the high notes abuse their senses with in-ear headphones and with the bass turned up to 11!
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There is a difference between ultra cheeeeep ( comes with the box and is made for lowest possible cost using poorest material that will last out the warranty period, which is mostly a taillight warranty anyhow) and a better connection. Mid price ( and this means not that overpriced thick cable from a certain company that hypes it) will be no worse than the snake oil stuff. The high end stuff just looks nicer, may influence your perceived response as well.
Just remember the mains coming in is carried on cables that are sometimes a century old, and are often rather noisy. The high price is just to pay for the advertising.
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I am always amused by the nutty ideas of hi-fi fanatics, they fret about amplifiers introducing .001% harmonic distortion and don't worry about the distortion introduced by FM radio stereo decooders, connect their loudspeakers with 100 amp flexable cable worrying about a few milli ohms of resistance when the innards of the speakers contain 15 ohms worth of regular wire
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sadly my ears are too shot with 15 years of pub cover band guitarring, i do like the shiny things though...
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Just remember the mains coming in is carried on cables that are sometimes a century old, and are often rather noisy. The high price is just to pay for the advertising.
If you've go century old wire in your house, it's probably about time for a remodel! The original Knob & Tube wiring is supposed to be pretty dangerous, especially after it has lost most of its original insulation, if it ever had any. Outside, of course, is different.
Gold plated connectors look sweet ;)
But, I'm not going to spend a wad of money to plug a gold plug into a brass socket.
I suppose I could imagine a possible advantage of shielded power cables if you allowed a coil of unshielded audio cables to rest on top of a coil of unshielded power cables. But, then your solution might not be to buy a solid gold power cable.
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I wonder how many
idiots with more money than brains hi-fi officianados have coughed up the money to buy these?
Ah, the power of marketing!
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I have some ( didn't pay for them - got out of recycling bin) and they are no different than good ones. Just look nicer.
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Topic: Worlds most expensive kettle leads
I find find that they ionize my water better than a common power cord. [;D]
It cures the common cold.
I get more brown hair and less grey hair.
It smooths wrinkles.
Increases stamina.
And adds 10 years to one's life!!!
[O8)] [:)] [;)] [:D] [;D] [8D]
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As a sheepie I of course have quite a high-end system !...erhmm...I'm quite embarrassed to say what it's worth but as someone who for seven years owned two specialist audio stores and having listened to quite literally many hundreds of systems and conducted even more number of hi-fi demonstrations I can vouch that for the audiophile out there, even the mildest hint of an increase (nay...a soupcon !) of extra clarity that brought the experience of their music close to the sound that the engineer in the studio intended it to be heard to, was a worthwhile goal. I regularly conducted trials of systems costing many thousands of pounds and it just did not stop at high end audio cables. The positioning of the speakers in relation to the room schematics, the characteristics of the room itself, be it carpeted, have furnishings etc etc....the height at which the speakers stood in relation the the listeners ear (specifically the HF tweeter), the platform that the speakers stood on, the rigidity and isolation properties of not just the stand that the equipment stood on but the stability and isolation of each component too all played a vital role. Then comes the interconnects and speaker cable and pwer leads and mains purifiers. Interconnects and speaker cable needed to be as short as possible, speaker cables ideally the same length. The quality of the termination plugs on both ends was vital.
From their point of view, it would be silly to invest £3000 in a cd player and then connect it to a £3000 amplifier with a £20 pair of interconnects. And then to connect the amp to a £4000 pair of speakers with cable that cost £3 a metre. Why have all that Rolls Royce quality inside when using "Lada" connections. Lets not forget also that it may not be one amp....no no..they may decide to bi amp...or even tri amp via a pre amp..i.e take a stereo amplifier and break it down into several individual components and feed the speaker drive units with individual isolated power, this woudl of course require even more runs of deliciously expensive speaker cable !
Forget tone controls...anything like that in a system is another component for the signal to travel through and to become tainted by........no...change the system instead to achieve the desired sound i.e: change a component or try a different cable. I'd just as often do demos just for interconnects and speaker cables alone.
If headphones were being used....forget the headphone socket...buy a £500 headphone amp and use a £1000 pair of heaphones..then you can use a headphone pre-amp and control amp too !
When it comes to the audiophile, the true perfectionist who music is a very serious passion then even the slightest nuance makes a big difference. And yes, then comes mains purifiers that can get rid of all the RF interference and clean up the power so that the components are receiving clean power with no fluctuations.
Once whittling down the number of systems/components in our demo rooms ....after a few hours then the client would take the system home for a home trial over the weekend...such is their passion. You simply must try it out in your own home....and of course...you must not play the system from cold...no no...turn it on...get it running for an hour before use...it has to warm up.
Fact is..the audiophile...it IS important and in the many many hundreds of hours I have spent listening to systems I can say that when your ears are in good order then you can indeed hear the differences. Some systems may offer more more three dimensionality...putting you right in the middle of stage or just in front of it when set up correctly. This is where speaker arrangement is so important. One interconnect may add a dash of extra midrange whilst another might tighten the bass.
After the system has done all the hard work then this is why good quality speaker cable is vital. You want to maintain that effort put in by the system and have the signal sent to the drive units in it's pure form.
You could also consider breaking down a CD player into a transport mechanism ie just the platter to put the cd on and then connect it (via more lovely expensive cable to a high end DAC and then again (via eevn more lovely expensive cables ) to the amp.
And when it comes to turntables....oh my !...you got the arm, the stylus cartridge, the isolation plinth, the plnth itself etc etc
I have to say that I love music with a passion...I love my high end system but I am not an audiophile. I do see/hear the differences that cables make..even the differences that system equipment stands make but past a certain point it's a law of diminishing returns (in my opinion) and if the client was happy that they could sincerely hear the difference then spending oodles of dosh on a cable to them was worth every penny. In a lot of cases it was not upgrade the hi fi but change the cables instead.
Some would have even dedicated music rooms..furnished appropriately and sound-proofed accordingly!..Hey...a man (and the occasional girly) has to have a hobby eh ?
They were happy...I was quids in !!
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I have to say that I love music with a passion...I love my high end system but I am not an audiophile. I do see/hear the differences that cables make..
The question is not about shielded audio cables, but rather about a shielded power cable.
Personally, I don't like using 18 gauge power cables for anything, but I suppose they are ok for some things.
Have you tried a controlled/blinded experiment with the power cables? Have the spouse swap the $2000 power cable for a $5 power cable (12 gauge or 14 gauge if you wish). Then see if you can tell which cable is being used without seeing it.
Assuming you don't have a loose connector, my bet is that you would be unable to tell the stereo performance between the $5 power cable and $2000 power cable. Coolness may still count for something, but that is a lot of dough for a cool cable.
I suppose if you are working on commission, then selling as many $2000 power cables as possible is good. [:)]
Now, there are some good $50 or $100 surge protectors. APC and Isobar make excellent surge protectors, and might be a good investment for your arm and two leg stereo equipment. I don't think I would add a UPS unless you are dealing with computer equipment. Would a power outage scratch an LP?
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£1999
all those nines in the price tag reminded me of this ...
https://secure.wikimedia.org/wikipedia/en/wiki/I_Am_Rich
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In all of my studio wiring I use a balanced system; put simply, this means that the signal is applied across two conductors in the cable, which is surrounded by a screen. The signals in the two conductors are subtracted from one another in the target component. And because any noise induced in the line will have occurred in both conductors equally, when this subtraction takes place the noise is removed and only the original signal remains.
This is particularly important when long cable runs are used, and under circumstances of close proximity to dirty sources (like mains AC, transformers and so on, as opposed to the porn channel on TV). Most high-end and professional systems operate on this basis.
In terms of the huge spend on audiophile gear, I agree with Neil that it's very much in the trained ear of the beholder. After 10 years of making radio programmes and podcasts, I can hear almost every edit point and cut that other producers have made in their broadcasts. But Before I "got my ear in" like this, I was oblivious to all of this, as, I'm sure, are most of the general public.
Chris
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I'd just like to thank neilep for his entertaining insight into the world of high end audio - a good read and a good contribution. Obviously there must be differences to be heard of companies would not sustain their markets, whether peoples perceptions are aspirational and tangible is an interesting debate - what is a significant improvement for some may be negligible for others depending on the outlay. I'd like to ask neilep for his opinion on the power cables. I can see that different speaker cables have different impedance, capacitance and resistance which can colour the transmission of different frequencies, I can hear this in good quality long guitar cables. But what about the power leads? Is it just that having bought a high end amp for £11,000 they cannot face using a £3.50 power lead? Can a significant sound difference really be heard by spending £1999 on a power lead?
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This is one of the most interesting discussions on HiFi that I have come across. I think Neil's input is very interesting. I can't disagree with the idea of anyone spending many £1000s on HiFi not wanting to take a risk on a few quid of mains cable. There are plenty of reasons why you may want to screen power cables from RF interference (switching spikes mainly) but it really only works if the power supplies in the walls are also screened, which is unlikely in most homes. In fact, the HiFi equipment should really be designed to adequately filter such interference.
At the end of the day it is down to marketing a product to get as many sales as possible and that some people will buy anyway because the money is not so importent. The majority of people cannot discern whether the manufacturers claims make any sense so there will be sales if the bullsh*t is good enough anyway. As for listening tests, these are VERY dubious unless over a range of music, in a near perfect environment and have a large number of "testers". As I think Neil points out, the environment and positoning of speakers is of huge importence. If individuals can discern some differences in a listening test, they may wish to make decisions on that basis, but it would not necessarily be reliable evidence on which other people should base their own decisions.
If you want to hear the ultimate in HiFi then go to listen to live music. Of course you have to put up with the room/hall acoustics and a noisy audience, but it is the music that should matter. Even then there are few live music events are not electronically amplified, and with imperfect speakers, - actually I find that most sound engineers seem to over-amplify to the point of ear damage, let alone distortion, even for music genre that would not normally be associated with being loud.
I know of someone who equipped a studio for a very well known popular singer/pianist He specialises in this field. He supplied custom designed systems with not only gold plated connectors but gold plated knobs! If you can afford it then why not? It was VERY expensive. Most of us try to be rational though as funds are more limited.
There is so much ill-informed bullsh*t in this business because, as the saying goes, bullsh*t baffles brains. I also find it difficult to appreciate why anyone would think music on vinyl sounds better than a high quality CD - there is not a lot of justification for this by almost any scientific measure of quality. Perhaps there are those who think the directly-cut wax cylinder is better again.
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I'd just like to thank neilep for his entertaining insight into the world of high end audio - a good read and a good contribution. Obviously there must be differences to be heard of companies would not sustain their markets, whether peoples perceptions are aspirational and tangible is an interesting debate - what is a significant improvement for some may be negligible for others depending on the outlay. I'd like to ask neilep for his opinion on the power cables. I can see that different speaker cables have different impedance, capacitance and resistance which can colour the transmission of different frequencies, I can hear this in good quality long guitar cables. But what about the power leads? Is it just that having bought a high end amp for £11,000 they cannot face using a £3.50 power lead? Can a significant sound difference really be heard by spending £1999 on a power lead?
Thanks Sprool.
I personally do use the power leads that came with my amp, cd and turntable but I do have them all plugged into a high(ish) end mains purifier. The power cables do not just simply transport current from the source to the equipment. They can add outstanding improvements to your listening pleasure through (so called) advanced filtering, as well as providing clean, uniform currents which improve the clarity and timing of your audio.
The mains purifier leads I have are enhanced with silicone rubber insulation, as well as silver plated copper, and can offer various benefits to the clarity and quality of audio and also visual reproductions
Further improvements can be made (believe it or not) by cryogenically treating the cables !!..yes..indeed !..I can't explain the chemistry/physics of it but reduce the temperature of the leads to cryo sub zero temps and cook them there for a while really changes some of the properties......for the better. I've conducted blind tests between cryo treated mains leads against their non cryo treated counterparts and the results have been beneficial !
In my humble opinion....If you have invested in a real quality amp..I would consider trying a news mains lead that helps to purify the source electricity. After all...besides rewiring the whole house....cleaning up the power source that feeds all the components does help....but I would always suggest to try and demo it if possible.
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This is one of the most interesting discussions on HiFi that I have come across. I think Neil's input is very interesting.
Awww..thanks Graham !
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By way of balance, as this is a science website, I can see very little scientific justification improving mains leads. By all means add a filter if there is any problem with noise spikes from other household equipment and avoid "earth loops" i.e. Star connect the equipment earths and have a single ground path. Neil, if you think you get better sound from an amplifier with special insulation, cryogenically treated wire etc. then that's fine, but it is a huge stretch to scientifically justify any of this.
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Right! That's it! I'm off to start a firm making Methanol Fuel Cell 'Separates'.
Watt What better way to control the quality of your electrical supply than to make it 'locally-sourced'?!
If a lead can go for two grand, then an even Eight K for the dedicated F.C. system is practically giving it away!! [;D]
Of course, you'll have to buy my special audio-specific Methanol refills for the system.
Warning! - Powering off standard naphtha could ruin your listening experience!
[;)]
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Peppercorn, I wish you well with your methanol fuel cell project.
Once you have got the rich "audiophiles" hooked on the idea I will start marketing my hydrogen powered fuel cell technology. (As used by NASA!).
As long as I get the marketing hype right (and I remember to gold plate things for no clear reason) their insatiable demand for "new stuff" in the name of audio excellence should get me well onto the gravy train.
In the meantime, can I sell you a green marker pen for a tenner?
Of course, if anyone does a double blind trial we are both in trouble but nobody has bothered yet, so I guess we are fairly safe.
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The cryogenic line is interesting, I've heard this before, been thinking how it can make an impact from the physics/materials science angle but not sure I can concoct anything credible at this stage. Some rearrangement of metal crystalline structure to a tidier more efficient conductor pathway would seem to me to require a higher energy level to shuffle stuff around (like high temperature annealing to remove imperfections and make metal harder) and very low temperatures would do the opposite.
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By way of balance, as this is a science website, I can see very little scientific justification improving mains leads. By all means add a filter if there is any problem with noise spikes from other household equipment and avoid "earth loops" i.e. Star connect the equipment earths and have a single ground path. Neil, if you think you get better sound from an amplifier with special insulation, cryogenically treated wire etc. then that's fine, but it is a huge stretch to scientifically justify any of this.
I can only vouch for my personal impressions during listening tests...and I can't explain the science to you I'm afraid..it's way beyond me !.........Of course being in the trade at the time...I paid trade prices and was also able to claim back the VAT too !........Now....in a different field altogether..i would not spend anywhere near the amount the retail value of the components were...but all I can do is defend my aural perception.....and not just my own .....my clients too who were able to take the cables home and try them themselves in their own homes with their own equipment and probably their friends and familys opinions too ! :)
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Neil, I would be impressed if anyone could explain any improvement in sound quality by use of such cabling unless the equipment it was supplying was of such poor design that it was rendered particularly susceptible to the nature of it's power supply cable, which, from what you have said, seems unlikely. However, I do not doubt the honesty of your belief in your observations though would venture to say that the power of suggestion may have come into play. Proper double blind testing would be more convincing. I have to say that if your observations are correct then I am at a loss to explain such an improvement in sound quality. If you have a reference to the special cabling I will see if there is anything more to it that I can see that could provide such magic. I remain sceptical though.
As for cryogenic treatment of cable... the mind boggles. What is meant by a more efficient current pathway? I can only think that there is some annealing effect. What could this do to any advantage? It could, I suppose,
1. slightly change the resistivity of the material
2. slightly reduce the 1/f noise
In my opinion, any such change in these factors (and it would be very small), in mains cabling, should not influence the sound of any equipment being powered through it. Any impact from these factors will be hugely swamped by whatever is on the mains supply anyway and/or will be filtered by the subsequent power supply circuits.
It may be more effective to get a priest to bless the equipment before use!
I bet someone comes up with concrete proof that it all works now I've said all this ;)
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I have no doubt that Neil's observations are correct. It's just that the reason for them lies in psychology rather than physics.
http://en.wikipedia.org/wiki/Suggestion
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Posted by: graham.d
« on: January 15, 2012, 20:16:31 »
Neil, I would be impressed if anyone could explain any improvement in sound quality by use of such cabling unless the equipment it was supplying was of such poor design that it was rendered particularly susceptible to the nature of it's power supply cable, which, from what you have said, seems unlikely. However, I do not doubt the honesty of your belief in your observations though would venture to say that the power of suggestion may have come into play. Proper double blind testing would be more convincing. I have to say that if your observations are correct then I am at a loss to explain such an improvement in sound quality. If you have a reference to the special cabling I will see if there is anything more to it that I can see that could provide such magic. I remain sceptical though.
As for cryogenic treatment of cable... the mind boggles. What is meant by a more efficient current pathway? I can only think that there is some annealing effect. What could this do to any advantage? It could, I suppose,
1. slightly change the resistivity of the material
2. slightly reduce the 1/f noise
In my opinion, any such change in these factors (and it would be very small), in mains cabling, should not influence the sound of any equipment being powered through it. Any impact from these factors will be hugely swamped by whatever is on the mains supply anyway and/or will be filtered by the subsequent power supply circuits.
It may be more effective to get a priest to bless the equipment before use!
I bet someone comes up with concrete proof that it all works now I've said all this ;)
Posted by: Bored chemist
« on: January 15, 2012, 20:44:23
I have no doubt that Neil's observations are correct. It's just that the reason for them lies in psychology rather than physics.
http://en.wikipedia.org/wiki/Suggestion
It's been six years since I was in the business.....I wouldn't be surprised if there are newer techniques of dealing with cables to make them more aurally attractive !!...especially attractive to the retailers and manufacturers bank accounts.
It is entirely possible that from a retailers position we wanted to hear a difference to sincerely convince the advantage to consumers who wanted to hear a difference also. In most cases, all demo tests of cryo cables were done blind against their non cryo counterparts. This was essential but I do understand your scepticism and it's possible that (as a retailer) I was susceptible to the clarity and definition that a cryo treated cable affected my bank balance !
Hey..look what I just found http://www.thenakedscientists.com/forum/index.php?topic=9648.0 seems I brought his up before !!
There are quite a few links out there...here's another http://www.nitrofreeze.com/cryogenic-audio-electronics.html
http://www.hydrogenaudio.org/forums/index.php?showtopic=36908
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Hmmm
The question remains whether there was actually a "trial", or the manufacture's website is made up of opinion.
And, if there was a trial, how was it actually controlled. There have been many questions about a possible association between funding source and trial outcome.
Article finds positive association between commercial funding and trial outcome (medical)
http://fampra.oxfordjournals.org/content/18/6/565.full.pdf
Article does not find an association between funding source and trial outcome (medical).
http://w02.biomedcentral.com/1472-6963/2/18
Keep in mind the distinction between wall power cables, and speaker wire cables. I would think you would have to look far and wide to find any benefit of going with $1000+ external power cables. Speaker wires might be another issue.
If I was really concerned about fine points of resistance in my speaker wires, rather than sourcing questionable cryo-treated wires, I'd hunt down some surplus cable-TV wires... not the little ones... I mean the big ones... say coax cables about 1" in diameter. [8D] They aren't too flexible, but are well shielded, and have a large enough conductor that you won't be worrying about resistance.
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I only use superconducting cables on my audio equipment, and my listening studio is an underground anechoic bunker (RF and audio) that's powered entirely by submarine batteries. Unfortunately, none of this seems to make the slightest difference when I play my (vinyl) Led Zeppelin collection.
EDIT: To my ears, Cream sounds pretty much the same too, but Mrs G claims Barry Manilow sounds much better.
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Inside the amplifier from which the speakers are fed you will find a common or garden electrolytic capacitor with compression joints connecting its output transistors via thin conductors to the output terminals.
Inside your speaker case you will find inductors and capacitors feeding the moving coils of the speakers commonly with a resistance of 15 or so ohms.
How can it make the slightest difference if the two are interconnected by 1 ohm or so of common cable or 001 ohm of fancy flexible oxide free 100 amp cable.
All you have to take care of is that connections are made securely (you could solder them!).
the power level in the speaker cables is such that no conceivable amount of electromagnetic fields could be audible.
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Syphrum, a lot depends on the speaker design and the nature of any crossover circuits. However, generally there is more reason to have a low impedance connection between the amplifier and the speaker drive units, although I would not go for the need to have this "magic" cable. The amplifier will have a very low impedance output which can damp overshoot in the speaker. Putting series resistance in the way can reduce this effect. I don't know whether this is audible, but at least I can see some scientific justification here.
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If this was a real concern the solution would be to use 4 wires, two to carry the power to the speakers and two to return the feedback to the amplifier directly from the speaker teminals.
This is the normal practice when a regulated PSU has to be fitted someway from its load.
there is no reason why the amplifier cannot be arranged to have a negative output resistance so that the resulting resistance is zero at the speaker terminals.
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I believe a "Kelvin" type connection is indeed used in some modern speakers where the power amplifier is in the speaker cabinet. There are even some speakers with optical feedback from the cone! I think a negative output impedance would be very difficult to control in any open loop way and would lead to oscillation. In theory you are right that you could use a 4 wire system on any speaker arrangement. There may be some care needed to avoid the amplifier oscillating, though this should not be a huge problem providing the amplifier's gain rolls off before the MHz region. It would be a lot cheaper than the hyper low impedance cable but it may be that manufacturers would not like to add this sort of complication where it relies on more things for the customer to get wrong.
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When I first heard a very faint "shhh" noise marking the end of a drum loop on a dance track I was listening to, I relaised that my (second hand) pre/power amp combination was better than the music I was listening to. I decided that audiophilla was not for me...
So far have my standards slipped, i no longer complain about MP3 as a format (that much).
Thanks Neil, you saved me regurgitating what my audiophile vinyl loving brother tells me...
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I'll stick my neck out and bet a pound that hi fi audiophiles who spend £1000 on a power lead, £11k on a CD player and same on an amp and speakers don't listen to much drum'n'bass or disco tracks in MP3 format ;)
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there is no reason why the amplifier cannot be arranged to have a negative output resistance so that the resulting resistance is zero at the speaker terminals.
I actually tried that forty years ago. I had applied the same technique to drive DC motors with great success, so I "extrapolated" that the same idea would work when driving speaker cones.
Didn't work for toffee!
I figured the only way to get it to work was with some sort of independent positional transducer - probably optical, but I had neither the time nor the means to muck around with it further.
Still, it's an interesting idea to make the cone be exactly where you want it to be rather than where it figures it ought to be. Whether this will make the slightest difference to listening enjoyment is or not is unknown, but it's probably unlikely. However, that's not the point of audiophile systems. I figure if you spend enough on it, you've pretty much got to enjoy it.
I think the right appproach is to treat the entire "ensemble" (recording media, amps, speakers, the room acoustics) as a sort of musical instrument. If you happen to like the sound it produces, you are good to go.
I also suspect we are influenced by the aroma the equipment gives off. To that end I plan to put a new fragrance on the market called "Eau de Mullard EL84".
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Right now all I need is not to have a blown left speaker cos I had System of a Down / Toxicity on tooo loud this morning.
For wanton idiocy - I had a valve/tube based ipod dock for about 5 weeks. It was nicked and I spent the insurance on something else and re-used the boring old cheapo old i had for years
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Some systems can be too revealing !...So many ' bottom-lines '...however the fundamental main source of the sound is the media that it's been recorded on. Everything else in the equation is designed to just faithfully reproduce it to the level that was recorded and laid down by the engineer in the studio. He/She had an intention as to how the recording should be heard and that is what the audiophile trys to achieve. So........ transparency is the goal here. A badly produced cd on a very revealing system can reveal all the flaws that are not intended to be heard....however and I can attest to this very much...a revealing system can amaze you by treating your ears to a three dimensional sound-stage and by revealing sounds and instruments that you never heard before...never knew that were there.
MP3's are as you all probably know are compressed and the compromise is made by missing out frequencies that can't normally be heard by the ear...however, there is argument that these frequencies that can not be heard do have an effect on the ones that can be heard and this is mentioned a fair bit by the audiophile who remains at a loss when confronted with a medium that does not produce the entire frequency spectrum. I prefer Cd's myself and regularly enjoy the warmth of vinyl too. But I also love my ipod too.
Some CD's are notoriously produced to sound harsh...I believe some of the early OASIS cd's were designed to sound quite raw and on a revealing system displayed themselves so.
I know this whole thing is a contentious issue but when dealing with an audiophile...it's their passion !!..their hobby !....I suppose it's all down to how much in love with music or sound reproduction.
If I was a top serious chef I'd buy a £100 knife and equal quality set of pots and pans etc......know what I mean ?
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Right now all I need is not to have a blown left speaker cos I had System of a Down / Toxicity on tooo loud this morning.
For wanton idiocy - I had a valve/tube based ipod dock for about 5 weeks. It was nicked and I spent the insurance on something else and re-used the boring old cheapo old i had for years
Good album !!
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I'll stick my neck out and bet a pound that hi fi audiophiles who spend £1000 on a power lead, £11k on a CD player and same on an amp and speakers don't listen to much drum'n'bass or disco tracks in MP3 format ;)
I love drum ' n bass !....Adam F ?
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Gold plate a fuel cell? Never! You need platinum plate, and rhodium alloy for the interconnects ( as Pt is cheaper than Au these days) along with solid PTFE insulation, and glass housings so you can see the reaction.
I am using an old Power Wedge 214 for my computer, mostly because it has 8 outlets, although I did remove the one isolating transformer ( crispy) from it. Needs better mains filtering though, am looking to add more brute force to it some day, have plenty of old filter modules to put in, along with decent chokes.
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Right now all I need is not to have a blown left speaker cos I had System of a Down / Toxicity on tooo loud this morning.
For wanton idiocy - I had a valve/tube based ipod dock for about 5 weeks. It was nicked and I spent the insurance on something else and re-used the boring old cheapo old i had for years
Good album !!
Have you seen the Lego version of chop suey. Brilliant. Will find a link when I am not on my phone
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£100 kitchen knife? Really Neil, you have to go up market :)
http://japanesechefsknife.com/SPECIALS.html
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£100 kitchen knife? Really Neil, you have to go up market :)
http://japanesechefsknife.com/SPECIALS.html
Cripes !!..Kill Bill Meets the Food Network !...Thanks Sprool ! ;)
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'tis a thing of great beauty though but my budget will not stretch to such luxuries. It would make an ideal cable splicer for Nordstrand, I'm surprised they haven't entered into a business co-op yet.
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Neil, I agree that MP3 is imperfect; it is highly compressed however. I don't think anyone would try to say MP3 sound is HiFi, but it's fine for listening to some music, perhaps in the background or in the car.
As a matter of interest there are compression systems that are designed to encode voice at 600 bits/second and do it so that the voice retains its tone qualities and (say) emotional content. It is far from HiFi and makes a complete mess of music, but the voice and a variety of background sounds are tolerably good. The person's voice can usually be recognised for example and, of course, the words understood. Such "vocoders" are used by the military and by fire/police/ambulance services to allow smaller bandwidths for digital data transmissions over radio, though, more generally 2400b/s is used for near toll quality (good telephony standard) with added error correction (to maintain the radio range) to make it 3600b/s overall.
To get back to HiFi, all studio work now is digitally recorded, as far as I'm aware (unless specially made), with at least 20 bit words and at a rate of 176 kwords/sec. A reason for this is so the multiple tracks can be mixed and remixed without causing any audible deteriation in sound quality. If you go to a live concert you will also find much of the sound equipment will be digital nowadays - certainly the best stuff. Many wireless microphones use some degree of compression - not generally well advertised - and the latest ones send the data in digital form. Listening to such recordings on vinyl seems a complete nonsense - though I don't suppose that would be an option nowadays. Generally I like 90+ dB signal/noise ratio rather than the 50dB or so (plus the occasional pop) you get from vinyl. Also, sounds recorded on vinyl are usually "companded" - a form of analog compression - the amount varied from company to company. If it is not companded they cannot cope with the dynamic range of many classical music pieces; the quiet parts would be buried in the noise or the loud parts overmodulated so that the stylus could not track the groove modulations without distortion. If anyone wants to purchase my numerous LPs (Classical, Popular, Jazz, Folk - no C&W though) I would accept any reasonable offer :-) None have been played on anything but a Shure V15 cartridge with an SME arm - I also still have a pair of IMF TLS50 speakers which are surplus to requirements now and take up a lot of space - very good for organ music!
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no C&W though
Well, she-hit Graham! Ain't you ever heard of Sydney Devine?
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... If you go to a live concert you will also find much of the sound equipment will be digital nowadays -
Including real-time pitch correction (autotune) ...
before ... http://www.antarestech.com/downloads/audio/BeautifullyBad.mp3 X¬o
after ... http://www.antarestech.com/downloads/audio/BeautifullyGood.mp3
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With compression and loss I did an experiment when transferring my vinyl to digital, and found I could tell the difference between a 128k encoding and a 256k encoding. I was using Audacity and LAME, so decided that the format would be 44.1kHz 320k in future. All except one LP, which was done at 48k WAV as I needed to change the samling rate to compensate that I do not have the ability to play a 16 2/3 RPM record. Worked out well after stretching the play time, then done at the same rate as the rest. 78's got the same, though they all had a varying amount of dehiss applied to get them to be less noisy.
Bought a cheap USB cassette player now, doing tapes to Ogg now at high bitrates.
The listening tests were done in a quiet environment, with old but still good consumer equipment. Better than the horrid stuff you get these days as a music playback system. No high end stuff, just old Kenwood separates, and decent speakers with the cabling being a twisted pair - Cat5 cable actually, lots of it around and using all 4 pairs in parallel. Better than the cheap twinflex it originally came with.