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USB CABLE

gustav_errata said:
You are over-fitting the analogy. My point was simply that if you want to identify the effects that a cable might have on noise, as Amir explicitly stated in his concluding remarks of the Nordost cable, you don't use a DAC that is known to effectively reject noise. Just as if you are testing the effectiveness of an antibiotic and you performed the tests on a known antibiotic-resistant strain, you would be rejected by the editors without even being sent out for peer review. The analogy is in the big picture, not drawing direct comparisons between the antibiotic and the cable and the bacterium and the DAC. FWIW, you originally quoted a repeat of the analogy, which I originally made much earlier in the thread with more explanation but I can't be bothered to find it to link it directly.

Edit for clarity: the overall point is that the ASR review of the Nordost USB cable is a waste of the server resources that it takes to store and serve it over the internet because it is 100% uninformative.

If the problem is noise in the DAC, and someone's DAC is indeed susceptible to this and they have their own reasons for not wanting to switch DACs, then they are free to explore and discuss whatever ways to treat it that they want, even if that includes expensive cables. Who am I to judge, with my £200 Cambridge Audio DAC and £6 USB cable?
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Hi Gustav,
I don't think we are a million miles apart, and I can see why you say I am over-fitting the analogy, but what I am tryign to do is to make a slightly different pooint using it. The point is that this idea -that what usb cables are for is to ameliorate (in a roudabout way) the suscpetibility of certin dacs to noise- is an ex post facto one. What the cable manufactuers (and reviewers) generally claim is to make the sound better in general terms (see the wireworld blurb) and in ways and using materials which do not appeaer to have been specfied for this purpose. They don't say, that their cables are not going to work with dacs which are not susceptible to ground noise loops (and not just becasue they don;t say their cables are there to do that job). The only reason for alighting on the noise idea is that some minor effects have been thrown up by certain measurements (once again showing how measurements show up the inaudible). It's a convenient measurable effect which we can pretend must be the reason for all of this.See jitter (effects of inaudible levels of as "explanation" for doubful reports).

It's a free country and if soemone wants to mess around with usb cables on the basis that they might have a noise problem which they solved, then this would be fine. But
-it still wouldn't make any sense as there would be better ways to skin the cat if there actually were a cat and it actually needed skinning.
-it isn't really why one would buy a usb cable of this sort in practice, it's just an apologist ex-post facto rationalisation and does not match the alleged benefits claimed or reported.
Finally- when dealing with the realy expensive end of the usb cable spectrum it really doesn't make any sense to be paying vast sums to address issues (even in a dumb way) which should not arise in any dacs with which such expenditure for the cable would be anything like commensurate.
 
Who reads manufacturer's advertising copy? As I keep saying, it was Amir that stated that all we're looking for in measuring a USB cable is alterations in noise.

Also, it's amusing that when a new DAC pushes ASR's SINAD measurements 1dB further into inaudibility, the ASR crowd lose their minds, Keith starts importing it, etc. When a USB cable decreases noise, it's dismissed as inaudible and therefore negligible. Whenever someone propose something, it's all "yeah but can you measure it?" but when measurements are presented, they're disregarded in whichever way is convenient. Audibility is a separate concern. If what you're interested in is lower noise, then a USB cable apparently can help even on a well-regarded DAC like the RME ADI-2-DAC.

Anyway, my only contributions to this thread were to point out the idiocy of Amir's approach sometimes (and you will not convince me that that Nordost USB cable test is anything short of idiotic and lazy) and that, to the best of my knowledge, no one is claiming that USB cables literally alter the music signal as argued against by the "bits are bits" people. I don't have a horse in this race otherwise. I just get annoyed by bad science and straw men (and now, moving goalposts).
 
Have you any measurements that show a USB cable audibly reducing noise, I don’t mind how poorly designed the dac is.
You mention that the RME is ‘helped’ by a USB cable I would be interested to see the link.
Keith
 
The wire world reduced noise on the cable, no change was seen on the output, so with the dac tested it was inaudible, with a worse dac it may have been audible.

I put ferrites on cables because some devices benefit from them, I'm not f'cking spiders.
 
the caretaker said:
I like the Dean Martin quote...its quite dark isn't it..in order to feel better you need a drink!
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kinda, I think it’s really about the strange but familiar point that happiness comes from relative rather than absolute relationships: hence you will be happier being the richest person in a poor circle than being (even if richer) the poorest person in a rich circle. And best of all, however badly off, you need to be better off tomorrow than today. And so, it would be great to discover that you have a soluble problem, because that means you can be happier soon. Equally, it is sometimes terrifying for people to have their problems solved, because up til that point they can imagine how much better things might be…
 
DGP said:
Reassuringly pragmatic USB cable test here
Very interesting ideed
DGP
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What an interesting video, never seen Purite Audio make anything similar...might be time to do so eh Keith? As I know you'll want to debunk this and you like visual proof an all that. Looking forward to it.
 
DGP said:
Reassuringly pragmatic USB cable test here
Very interesting ideed
DGP
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If I've understood correctly, he passed a digital signal through a USB cable to a DAC and then took the analogue from there through an ADC and recorded it. He repeated for each cable and aligned the recordings by identifying the same sample in each. The problem is that there is no "same sample" to align. The ADC will sample the analogue at slightly different places every time, so his alignment is off.
 
zarniwoop said:
If I've understood correctly, he passed a digital signal through a USB cable to a DAC and then took the analogue from there through an ADC and recorded it. He repeated for each cable and aligned the recordings by identifying the same sample in each. The problem is that there is no "same sample" to align. The ADC will sample the analogue at slightly different places every time, so his alignment is off.
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Wouldn't the same cable being tested twice and showing less error than that measured between different cables show that the effects you suggest are less than the differences between cables?
 
adamdea said:
kinda, I think it’s really about the strange but familiar point that happiness comes from relative rather than absolute relationships: hence you will be happier being the richest person in a poor circle than being (even if richer) the poorest person in a rich circle. And best of all, however badly off, you need to be better off tomorrow than today. And so, it would be great to discover that you have a soluble problem, because that means you can be happier soon. Equally, it is sometimes terrifying for people to have their problems solved, because up til that point they can imagine how much better things might be…
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That's a very fulsome response! You have clearly thought about this..we need the grass to be greener regardless of its actual colour...insoluble problems might be advantageous..if we solve one problem hopefully another will appear, because the alternative is worse..alternative being we have to face ourselves! All we do is find things to avoid this..hifi hobby..daytime TV, reading a book etc...imagine winning the lottery and then what? Happiness? Contentment? In a short time same as before..a luxurious same old? Only way to achieve happiness in my opinion is find it within yourself..no one can provide happiness..only yourself ( assuming happiness is important? ) I think its just a trick...as radiohead put it..no alarms and no surprises please...
 
Greyandy said:
Wouldn't the same cable being tested twice and showing less error than that measured between different cables show that the effects you suggest are less than the differences between cables?
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No. I predict that if he repeated the test multiple times with the same cable and using the same alignment technique he would get some with less audible difference and some with more. It's all about the clock in the ADC and where it is in its cycle when the recording starts.
 
gustav_errata said:
Sorry, not interested in dancing with you. I've said all that I wanted to say in that post and all my previous ones, including answers to both of your questions. If you're so interested, I invite you to print them out and re-read them at your leisure. No sense in repeating myself.
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Poor Keith, no dancing for you..always the bridesmaid and never the bride! Lol
 
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