rollintubes63 posts06-28-2019 11:20am@clearthink @wynpalmer4 is simply explaining in technical terms that most trained people use, but will be foreign to the lay person. Technical jargon can also be useful in obscuring the issues. It’s also an Appeal to Authority to the extent that because someone has technical knowledge it doesn’t mean they automatically win all or even any technical arguments. Two technically competent individuals may have entirely different views on a given issue, for example. |
Stochastic is random, such as the addition of noise to a voltage level.
Deterministic is due to the interference of the pulses (they're usually called symbols) with each other due to the fact that the bandwidth of the interconnect is not infinite and as a result the edges get "smeared". Because the edges are at variable times relative to one another the amount of interference varies from each bit of data to the next. This causes the point in time at which the data is detected to also shift from bit to bit causing jitter relative to the average. These two effects combined (plus other second order effects) are responsible for deterioration in the sound if they are not corrected. If the shift is too large the transition will not be correctly detected at all and the bit is either lost or misplaced and a data error occurs and is flagged by the CRC.
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I'm not using technical jargon to obscure the issues. Quite the contrary.
I'm happy to explain, however I'm also trying to avoid being condescending (and imprecise) in avoiding its use. Sometimes terms with precise meanings are necessary to add clarity to an issue, and sometimes those terms require a great deal of explanation that would just cause people to turn off. Better to try and explain as requested...
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@wynpalmer4,
I appreciate and respect your background on this matter and would like to know, or clear up, the matter of the signal being corrupted when being transmitted by a poorly made USB cable.
First, did you read the link I provided on the previous page and if so, did it correctly describe what happens with USB transmission?
Second, if so, then does it make sense that a corrupted data stream cannot be faithfully reconstructed on the receiving end?
All the best,
Nonoise |
Download your digital media onto a computer. The ripping process includes CRC checks for bit perfection. That way you can be certain that the bits out are what was intended to be recorded on the original medium and any discrepancies will be flagged.
This also applies for any lossless compression schemes such as FLAC.
After that, well you still need to have quality retiming etc.
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Are there any online reviewers you can actually trust these days?
I want to upgrade my system but all the High End stereo places
went out of business in my area and all that is left is Best Buy.
6moons seems like a decent site but I have no idea if the reviewers
are accurate or not. (Thanks)
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A sufficiently corrupted data stream cannot be reconstructed at the receiving end, but the corrupted packets can be identified and dropped.
This is quite audible and unmistakable. It does not result in the loss of ambience or differences in top hat shimmer.
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@jbrrp1
How do you fiddle with a USB cable?
I believe you, I just want to know how..
My biggest Holysh*t!! moment was better powercords.
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Please don’t misinterpret what I said. I didn’t say you personally were guilty of obscuring the issues. I was speaking generally. |
A sufficiently corrupted data stream cannot be reconstructed at the receiving end, but the corrupted packets can be identified and dropped.
This is quite audible and unmistakable. It does not result in the loss of ambience or differences in top hat shimmer. Agreed. The reviewer did state that it would result in dropouts, affect depth, dynamics, impact and sound staging. As for any effects on ambience and/or shimmer, I'd have to hear it for myself as I've heard differences in those aspects with different cabling and from cleaning up noise on the AC. All the best, Nonoise |
The word shimmer means different things to different people. It’s like the word soundstage or air. If only you could hear what I hear with my ears.
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@geoffkait
I don't think people really care what you might think of their CD
playback hardware if you were able to hear them in person.
I think it's ridiculous to not realize that top shelf CD Players
can sound as good or better than other mediums.
The Naim CDS-3 will smoke a lot of turntables and Wifi Flac
streaming setups. I have heard amazing A/B comparisons
and CD Playback can be breath taking.
CDs themselves can sound bad if they were recorded poorly.
Many CDs will always sound bad and so will LPs that were
recorded poorly. |
Agreed. My point is that the loss of a packet results in a discontinuity in the signal. In my experience such an event is audibly catastrophic and not in the least subtle and does not require audiophilese to describe.
USB interfaces will report packet loss, but I'm not sure that audio gear is able to enlighten the listener when such events occur.
I would imagine that computer based playback software would be able to report it, but I don't know that for a fact.
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Yes, many CDs are just dross, while a few are quite magical.
This applies also to high res recordings, but as always caveat emptor.
I know of one download that on my system sounds noticeably superior to the live performance of the same piece with the same two musicians but performed in a different hall than the recording and with the violinist playing a different violin- a, as he put it, "fine copy of my strad" and the pianist playing a Steinway model A rather than the recorded model D.
This is not just my opinion, other attendees agree.
The playback was over USB using an RME ADI-2 PRO FS, and using a non audiophile USB cable with an active extender.
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I always heard instant improvements with audio
and speaker cables. I never believed power cords
could make a difference because the house is wired
with cheap Romex but it knocked my socks off when
I tried better power cords at home. From that point
I learned to just listen with my ears and not ask why
or how something sounds different or better.
Another thing that baffles me is HDMI cables. I don't
know why, but I see slight differences with HDMI cables
on both my Pioneer Kuro TV and my computer monitor.
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tom32801
Another thing that baffles me is HDMI cables. I don’t
know why, but I see slight differences with HDMI cables
on both my Pioneer Kuro TV and my computer monitor.
>>>>>>There it is! I must have ESP. 😳
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wynpalmer
Yes, many CDs are just dross, while a few are quite magical. >>>>I can certainly understand why you would believe that but it’s not because the CDs per sec are dross. It’s because the playback system can not retrieve the data completely or accurately. It’s not even close. One’s hear is not particularly sensitive to various kinds of distortion present on almost all CDs when they are played back on home systems. But almost any yahoo with ears can hear the LACK of those distortions when they are removed. |
@wynpalmer4
Two questions:
1. Can a 1 be mistaken for a 0 at the usb receiver if the waveform is degraded enough?
2. If the DAC is receiving a degraded waveform and the data recovery circuitry is working hard to sort through it, does this circuitry not increase the electrical noise in the DAC? If so, is it negligible or does that just depend on the DAC design?
My approach is to try to provide the cleanest signal possible from streamer to DAC within reason, if for nothing other than peace of mind. This does not include cables made from unobtainium however. |
Just thought of another:
I upsample all of my PCM content to DSD 512.
Is the data recovery fast enough to handle a poor signal with that much data coming through?
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My approach is to try to provide the cleanest signal possible from streamer to DAC within reason, if for nothing other than peace of mind. This does not include cables made from unobtainium however. No need for unobtainium or exotic metals as long as you adhere to USB 2.0 regs, which require: copper wire of the appropriate gauges, a real aluminum sheath and not some aluminum vapor deposited onto some cheap, thin mylar sheet covering 100% of the cable, a copper sheath covering 65% of the cable, and able to meet transmission rates. Think of all the meat you buy and realize that not one major meat packing company meets USDA requirements, yet the meat has the USDA stamp of approval on it. Same goes for USB 2.0 compliant cables. Do your due diligence and you'll find companies that'll gladly appraise you of what's inside their cables, meeting or exceeding standards, that won't break the bank. All the best, Nonoise |
Just a FYI.
The reason redbook format has such low resolution, because at the time, you know back in the early digital age, the CD storage could not hold as much information as it does now. If redbook was to have the same resolution as SACD, the size of the disk would be huge which made it impractical for portability (for example a hand carried player). |
1. Can a 1 be mistaken for a 0 at the usb receiver if the waveform is degraded enough? It can get complicated. For CD, their is error correction. If a byte comes in with error, and if the error is not catastrophic, the error can be corrected. But if the error is catastrophic enough that cannot be correct, the next layer of defense is the missing data will be interpolated. Because the music data stored in the CD is interleaved, interpolated is possible. For example, if there are 20 consecutive bytes of error, they do not comprised a continuous stream of musical data, because of interleaved, the 20 bytes come from different segment of music. Based on CD spec, you could potentially drill a small hole on the surface of the CD and it can still work. Most of the differences you hear from different CD player probably not because of error because of power supply design, noise, the output stage, and of course JITTER. I am not quite familiar with USB protocol but I CANNOT imagine that it would not have error correction and interpolation, and that the data is not interleaved. If USB has all this characteristic, I don’t see how what I said above would not apply to USB as well. Again, I don’t think most audible differences you here is from bit error because it is just a small percentage of all the variables. Now if you hear scratchy sound or spikes like a damage cd, well that’s different. |
2. If the DAC is receiving a degraded waveform and the data recovery circuitry is working hard to sort through it, does this circuitry not increase the electrical noise in the DAC? If so, is it negligible or does that just depend on the DAC design?
It's a bit complicated because it's not like you have a usb data hooked up directly to DAC. You have a usb data that has to go to different hardware protocol before it gets to the actual DAC. And on top of that, you have the software on top of it to control everything. This could be a long explanation especially if one may not have a background in electrical engineer. Now there two different USB DAC architectures - synchronous and asynchronous. Synchronous was an old architecture which was susceptible to jitter and clock. Most DAC nowaday probably use asynchronous. This architecture essentially, at least in theory, eliminate the effects of jitter, which means even if the input USB data has a lot of jitter, the DAC will be affect. The detail why is a bit complicated. Now my turn to pose the question (especially to
wynpalmer4 since he claims to have a design background), because the asynchronous architecture essentially eliminates the effects of jitter, why then the USB cable would make any difference? (Assuming you still have bit perfect which is not that unreasonable) |
Come on...its a Nordhost product. Starting out it is well made, over priced and of questionable efficacy. A poor value even if it does make a difference. |
A poor value even if it does make a difference.
Why would it make a difference though? That is a question I'd like to know. |
@tom32801
The "fiddling" I did with USB cables is to try a few. I had started with a basic DH Labs USB cable, and I received a freebie Supra Sword USB cable rolled in with some gear that I bought, so I tried that. I could hear no difference at all. None. Then some months later the importer of my DAC recommended a Final Touch Audio Callisto USB cable that other owners were really liking. Wow. It was like when I discovered what a really good power cord brings to the party. My digital took some important steps to a truer sound, gaining some more information, and with an uncanny greater coherence and palpability, like the focus sharpened at the micro detail level and fleshed out harmonics, space, and dynamic shading a bit better all together. And really feeling coherent. The sum total is surprising to me, and it has certainly converted me to a believer that USB cabling matters. |
For very high frequency applications like USB cables wouldn’t pure silver strands or silver plated copper strands be best, given that the signals travel very close to the surface of the conductors? Controlling the USB cables for directionality - as Audioquest does - also seems like a splendid idea. 🤗 I also like their “shield the shield” idea. I’m a proud owner of Audioquest Carbon HDMI cables, which employ similar concepts. See link below for Audioquest web page for Carbon USB cable description, https://www.audioquest.com/cables/digital-cables/usb-a-to-b/carbon |
There is an excellent article from the late Charles Hansen Ayre designer about the USB DAC. Although the article does not about USB cable specifically, but it will give you understanding of USB DAC architecture in general and how the cable "COULD" affect the sound. I don't remember where it is but it used to be on Ayre website. If I can find it I'll post it here. |
For very high frequency applications like USB cables wouldn’t pure silver strands or silver plated copper strands be best, given that the signals travel very close to the surface of the conductors? Controlling the USB cables for directionality - as Audioquest does - also seems like a splendid idea. 🤗 I also like their “shield the shield” idea.
Actually for very high speed data, they don't really want it very fast. If you look at those signal on the scope, the rise time looks more like a sine wave than a square wave. High edge rate may cause a lot of EMI issues. |
If you’re referring to the speed of the signal there is virtually no difference through copper or silver. In both cases it’s near lightspeed.
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If you’re referring to the speed of the signal there is virtually no difference through copper or silver. In both cases it’s near lightspeed.
I was referring to the data edge rate, not the speed in term of data rate or propagation speed. The edge rate is the signal slew rate measured in V/sec. You were referring to propagation speed which is measured by (radiant/meter). What I was saying is that fast edge rate might not be desirable. If a cable made of silver, it will increase the edge rate which can potentially cause EMI issues and may end up having more jitter. It's not a simple one rule fit all sort of thing, and silver may improve other aspect of the data transmission, but with respect to edge rate, it does not mean the faster the better. With respect to USB asynchronous architecture, the jitter from the USB data stream is not an issue because the data is buffered before it is clocked to the DAC using a local clock that does not depends on the USB data stream. It's how the USB data stream may cause jitter down stream to the DAC. The faster the edge rate, the more like EMI will cause interference to ground, power and so on and ultimate jitter to the DAC. For synchronous USB, then may be silver could be better since it has faster edge rate and that could improve jitter. That's why I am saying there is no one rule fit all but depends on other factors. |
Isn’t slew rate a function of the amplifier? Not the conductor. The advantage of silver is that the resistance is lower. Maybe someone should come up with copper-plated silver wire. 😬
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The Final Touch Audio Callisto USB cable that @jbrrp1 mentioned that gave him excellent results is not purified copper, with gold and silver literally hammered (smithed) into it, or so it states on their website.
Looks like this jungle of cables are getting denser. 😄
All the best,
Nonoise |
Isn’t slew rate a function of the amplifier? Not the conductor. The advantage of silver is that the resistance is lower. Maybe someone should come up with copper-plated silver wire.
Yes, but the conductor does play a role. All cables act like some sort of low pass filter. If you model out a simple resister and a cap as a low pass filter, the higher the resistance will result in more low pass filtering. As you said silver does have lower resistance so the rise time won't be degraded as much as copper. In some cases having a higher rise time improves jitter but high rise time will also result in higher EMI. That's why most high speed data rate will have only enough rise time to get away with. It's a balanced act so it depends what you want to achieve, Also as I mentioned, there is no one single factor. It depends on the situation. |
I would buy a very reasonably priced USB cable from Monoprice or other legitimate dealer. Makes no sense to pay a premium for Nordhost cables when there has never been a verified test where anyone was able to tell the difference. Every serious, well known A/V organization will tell you that moderately priced digital (USB, HDMI, Ethernet) cables are all you need for 100% audio and video throughput and quality.
Don't be a dummy; spend your money like you have a clue. And don't be fooled by the pseudo-high tech babble you read here made up by self proclaimed pseudo-audio experts. That they buy these high priced trinkets says all you need to know about their qualifications. |
“Every serious, well-known AV organization will tell you...”
Blah, blah, blah, blah......🤗
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Just for the record, you have about 16,000 more "blah, blah, blahs" than I. Perhaps I have a life beyond Audiogon? |
@geofkait
Why do I care if you think my system sounds good. As long as I am pleased with it your opinion does not matter to me.It is there to please me not you.
Rollin
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In that case, if you’re pleased, I’m pleased. 🙄 |
@dynaquest4
Your broad pronouncements of what others should do seem presumptuous to me. Rather than living in the world of "shoulds", I would recommend you try the realm of "ears on" experience and try some cables to hear the difference (or not) for yourself. Experience trumps "theory", IME.
I'm an engineer, and I would have sworn that all of this cable nonsense just shouldn't, just couldn't make a difference. But sometimes when I have tried them there was absolutely no doubting the differences and the musical improvements in my system. Reluctantly, I have put some serious money into wire, and my ears are glad I did. That's my experience. You just cannot beat trying something yourself, rather than simply accepting conventional wisdom. |
My "broad pronouncement" represents my opinion, based, over the years, on many disappointments. Recently replaced the Kimber Kables to my main speakers because they were not long enough in our new home. Spent about (oh, my god) $35.00 with Monoprice. Result: the new cables reach, look good (what you can see of them) and no noticible difference in SQ. As expected.
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Nothing succeeds like success and failure’s no success at all.
Lead, follow or get out of the way. |
