Chris53
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Post by Chris53 on Nov 5, 2010 12:08:04 GMT
Now this might be opening a can of worms as I know there are people here who believe that fancy cables make no difference  but has anyone heard about the "High Frequency Termination Network" that DNM are suggesting people have fitted to their interconnects? www.dnm.co.uk/hftns.htmlIt sounds intruiging but is there any electronic sense to it?  |
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Deleted
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Post by Deleted on Nov 5, 2010 16:15:29 GMT
standard (even the cheapest) screened RCA cables can easily transfer 1MHz without any losses.
I know, I have measured it.
The info on the website is partly utter B and partly true. (that's the fun part)
Most RCA cables can even transport video (needs 10MHz bandwith at least)
cables upto 1m have no problems.
Of coarse everybody who is convinced that cables have limited bandwith and don't believe vendors who try to make (a lot) of bucks by selling you an idea is free to do so.
I for one will spend my money elsewhere.
This is my personal opinion by the way.
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Chris53
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Post by Chris53 on Nov 5, 2010 16:41:38 GMT
standard (even the cheapest) screened RCA cables can easily transfer 1MHz without any losses. I know, I have measured it. The info on the website is partly utter B and partly true. (that's the fun part) Most RCA cables can even transport video (needs 10MHz bandwith at least) cables upto 1m have no problems. Of coarse everybody who is convinced that cables have limited bandwith and don't believe vendors who try to make (a lot) of bucks by selling you an idea is free to do so. I for one will spend my money elsewhere. This is my personal opinion by the way. That's interesting, maybe I've misunderstood the website then because I thought they were suggesting that the cable does have a wide bandwidth and that was the problem and that their "filter", for want of a better word, would solve the problem by only allowing audio frequencies through? |
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Post by Deleted on Nov 5, 2010 17:05:19 GMT
standard (even the cheapest) screened RCA cables can easily transfer 1MHz without any losses. I know, I have measured it. The info on the website is partly utter B and partly true. (that's the fun part) Most RCA cables can even transport video (needs 10MHz bandwith at least) cables upto 1m have no problems. Of coarse everybody who is convinced that cables have limited bandwith and don't believe vendors who try to make (a lot) of bucks by selling you an idea is free to do so. I for one will spend my money elsewhere. This is my personal opinion by the way. That's interesting, maybe I've misunderstood the website then because I thought they were suggesting that the cable does have a wide bandwidth and that was the problem and that their "filter", for want of a better word, would solve the problem by only allowing audio frequencies through? I only skimmed over the article but was left with another different impression. I thought they were claiming their little do-dah filtered out the RF interference, within the range that effects audio signals, that they say are present in cables. I'm no DNM fan so can't be bothered to read it over carefully. |
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Chris53
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Post by Chris53 on Nov 5, 2010 17:29:34 GMT
That's interesting, maybe I've misunderstood the website then because I thought they were suggesting that the cable does have a wide bandwidth and that was the problem and that their "filter", for want of a better word, would solve the problem by only allowing audio frequencies through? I only skimmed over the article but was left with another different impression. I thought they were claiming their little do-dah filtered out the RF interference, within the range that effects audio signals, that they say are present in cables. I'm no DNM fan so can't be bothered to read it over carefully. I admit I only skimmed over it too but my impression is similar to yours but I wonder if it really does make a difference. I know that whatever muck is in my mains supply (electricity not water  ) is being helped by having a balanced mains transformer. I've often wondered how much RF might be affecting the sound too but ferrite rings on interconnects don't appear to make much difference so maybe RF isn't a problem for me anyway. I don't know enough about it to know if doing something would be necessary. |
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Post by Deleted on Nov 5, 2010 20:23:57 GMT
IF RF garbage creeps in the audio chain (from the mains or cordless telephones nearby) it will be common mode RF signals and thus the cable will not act as a guide wave but the RF will travel in that part of the conductor (wire) that has the lowest Ohmic value i.e. only the screen and thus not enter the audio path by means other then interference.
The IM problems associated with RF energy upstetting the input stage of amplifiers should (and in most cases is) adressed at the input of the amplifier if it is sensitive for this (most fedback amps are) and should, have a bandwith limiting filter present (like I mentioned in the first pages of the Panda thread)
If the amp does not have this (the Panda does not) AND there are RF signals in the signal path these filters (they are simple RC filters) might help. It all depends on the toptolgy of the amplifier too so will not result in degradation in every design.
Proper screened cables and good playback equipment doesn't have RF signals in it so you don't have to worry about it nor have to spend your money on these things.
It has a bit of truth in it, that's why it is great to sell.
Also there is a lot of snake oil and 'fear making' involved (must I use this because they say... and probably know)
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Chris53
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Post by Chris53 on Nov 5, 2010 21:07:04 GMT
IF RF garbage creeps in the audio chain (from the mains or cordless telephones nearby) it will be common mode RF signals and thus the cable will not act as a guide wave but the RF will travel in that part of the conductor (wire) that has the lowest Ohmic value i.e. only the screen and thus not enter the audio path by means other then interference. The IM problems associated with RF energy upstetting the input stage of amplifiers should (and in most cases is) adressed at the input of the amplifier if it is sensitive for this (most fedback amps are) and should, have a bandwith limiting filter present (like I mentioned in the first pages of the Panda thread) If the amp does not have this (the Panda does not) AND there are RF signals in the signal path these filters (they are simple RC filters) might help. It all depends on the toptolgy of the amplifier too so will not result in degradation in every design. Proper screened cables and good playback equipment doesn't have RF signals in it so you don't have to worry about it nor have to spend your money on these things. It has a bit of truth in it, that's why it is great to sell. Also there is a lot of snake oil and 'fear making' involved (must I use this because they say... and probably know) Ahh that would explain why they might make a difference with the DNM cables then because they are unscreened. They are charging a pretty hefty price (about £35 per phono plug) for these filters. That seems high considering they are just simple filters as you say Franz.  |
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Post by Deleted on Nov 5, 2010 22:54:33 GMT
unscreened cables are good for headphones and speakers.
I would NOT recommend unscreened cables for interconnects unless the audio signal, (which are asymmetrical) is converted to a symmetrical signal (like those used in professional audio (microphones e.t.c.).
Then the filters also will not be needed anymore as it is intrinsically immune for RF coupling from the outside.
They are out there to make a buck.
If they do not sell many cables and have to eat from the profits they need to sell it for a high price.
Doesn't make it better or higher value.
I find their theories flawed but that is my own opinion others might disagree.
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but has anyone heard about the "High Frequency Termination Network" that DNM are suggesting people have fitted to their interconnects?
) is being helped by having a balanced mains transformer. I've often wondered how much RF might be affecting the sound too but ferrite rings on interconnects don't appear to make much difference so maybe RF isn't a problem for me anyway. I don't know enough about it to know if doing something would be necessary.