What is the best Digital cable I can get to go between my BDP2 and B135-3-DAC?

0 Members and 1 Guest are viewing this topic. Read 3450 times.

newzooreview

make 'zeros and ones' sound better, or that it somehow changes the bits...

There aren't any zeroes or ones going through a S/PDIF, HDMI (I2S), USB, or Ethernet cable. These cables carry analog signals.

A DAC is an analog to digital to analog converter.

The analog signal coming into the DAC must be converted or interpreted into 0s and 1s. The quality of this interpretation depends on a) correct timing of the signal and b) noise or inaccuracy in the signal that inhibits the accurate interpretation into 0s and 1s.

A S/PDIF cable is, by specification, 75 Ohms, but the precision of the impedence on the cable can vary and, very importantly, the impedence at the connector rarely meets spec because testing, if any, is done on the unterminated cable. The Belden cable that Blue Jeans Cable uses is just +/- 3 Ohms. And that is just the slop in Belden's manufacturing of the bulk cable. Blue Jeans publish no data about the accuracy and precision of their terminated cables. I'm not knocking them. I use Blue Jeans coax as a baseline, and it is ok. But it's definitely not close to the best you can do.

Some S/PDIF cable manufacturers make the engineering effort and quality control effort to produce terminated cables that are actually 75 Ohm across the terminations on both ends. This requires labor-intensive tolerance control on the physical cable assembly (by hand and with component materials of better quality than a factory production cable sold at a price point to be "good enough"). This also requires careful hand termination and measurement of the final cable and rejection of cables that don't meet spec (e.g., increasing labor and materials costs).

Circling back to the question, I've been very impressed by the Stealth Audio Varidig V16. It's hand made to order in Maryland. Swapping that in for the Blue Jeans cable took the sound from enjoyable to excellent. When the DAC is getting more accurate 0s and 1s it makes a differend.

i've heard good things about the Siltech cables. The Siltech S/PDIF cable that is closes to the Varig in price is the "Classic Anniversary" but I haven't been able to find much about the testing or manufacturing precision.  https://www.thecableco.com/classic-anniversary-hf-digital.html

The Cable Co. has some cables available for home trial (their Cable Library). Definitely worth checking out.

Happy listening!  :thumb:

Chewbacca

There aren't any zeroes or ones going through a S/PDIF, HDMI (I2S), USB, or Ethernet cable. These cables carry analog signals.

A DAC is an analog to digital to analog converter.

The analog signal coming into the DAC must be converted or interpreted into 0s and 1s. The quality of this interpretation depends on a) correct timing of the signal and b) noise or inaccuracy in the signal that inhibits the accurate interpretation into 0s and 1s.

A S/PDIF cable is, by specification, 75 Ohms, but the precision of the impedence on the cable can vary and, very importantly, the impedence at the connector rarely meets spec because testing, if any, is done on the unterminated cable. The Belden cable that Blue Jeans Cable uses is just +/- 3 Ohms. And that is just the slop in Belden's manufacturing of the bulk cable. Blue Jeans publish no data about the accuracy and precision of their terminated cables. I'm not knocking them. I use Blue Jeans coax as a baseline, and it is ok. But it's definitely not close to the best you can do.

Some S/PDIF cable manufacturers make the engineering effort and quality control effort to produce terminated cables that are actually 75 Ohm across the terminations on both ends. This requires labor-intensive tolerance control on the physical cable assembly (by hand and with component materials of better quality than a factory production cable sold at a price point to be "good enough"). This also requires careful hand termination and measurement of the final cable and rejection of cables that don't meet spec (e.g., increasing labor and materials costs).

Circling back to the question, I've been very impressed by the Stealth Audio Varidig V16. It's hand made to order in Maryland. Swapping that in for the Blue Jeans cable took the sound from enjoyable to excellent. When the DAC is getting more accurate 0s and 1s it makes a differend.

i've heard good things about the Siltech cables. The Siltech S/PDIF cable that is closes to the Varig in price is the "Classic Anniversary" but I haven't been able to find much about the testing or manufacturing precision.  https://www.thecableco.com/classic-anniversary-hf-digital.html

The Cable Co. has some cables available for home trial (their Cable Library). Definitely worth checking out.

Happy listening!  :thumb:

So you're trying to tell me a USB cable transmits an analog signal?...

Speedskater

  • Full Member
  • Posts: 2679
  • Kevin
Nonsense!
The signals are digital. The carrier is analog, but so what?
Actually for 44.1 by 16 S/PDIF and cables 30 feet/10 meters or less, any 50 to 125 Ohm coax cable will work just fine.
Connector impedance is just more nonsense at low S/PDIF frequencies.
Those close cable tolerances are for pros doing long multi-channel unbalanced AES/EBU runs. Yes, untbalanced is better for long runs.

twitch54

man I'm glad I still listen to vinyl, all analog, all the time .......  :green:

RDavidson

  • Full Member
  • Posts: 2863
Nonsense!
The signals are digital. The carrier is analog, but so what?
Actually for 44.1 by 16 S/PDIF and cables 30 feet/10 meters or less, any 50 to 125 Ohm coax cable will work just fine.
Connector impedance is just more nonsense at low S/PDIF frequencies.
Those close cable tolerances are for pros doing long multi-channel unbalanced AES/EBU runs. Yes, untbalanced is better for long runs.

Close tolerances are bad for "consumer grade" gear, said no one ever. :roll:

Speedskater

  • Full Member
  • Posts: 2679
  • Kevin
Close tolerances are bad for "consumer grade" gear, said no one ever. :roll:
If it costs more, that would be bad for the consumer.
But Belden and other major industrial cable manufactures make excellent cables that don't cost more.
* * * * * * * * *
In fact if a 3 foot S/PDIF costs more than $25 it cost too much.
But then there are many good S/PDIF cables that cost less than $25.
On the other hand copper prices are sky rocketing, so be prepared for sticker shock or low availability.

RDavidson

  • Full Member
  • Posts: 2863
If people want to pay for better (far better) stuff, how is this bad for anyone? That's only your opinion and not a fact. Thank goodness we have more choices than very mediocre Belden wire. What do you think is better, mass produced steak at a buffet or carefully selected, cut, and cooked steak at a high end restaurant? Sure, one will cost more, but that's not the point. One is clearly better, and it is definitely not the buffet steak. If you're happy with buffet steak and it is the best you'll allow yourself to eat, that's your choice. Doesn't mean everyone else should agree with you. Enjoy what you like versus trying to convince everyone of how great buffet steak is. I've had it at a Golden Corral at least once. It is the equivalent of Belden. :lol:

Keep in mind we're on the Bryston Circle...a fine fine producer of many different cuts of the best Canadian beef...er...audio gear. :D
« Last Edit: 29 May 2021, 05:18 am by RDavidson »

cheater

  • Jr. Member
  • Posts: 23
HDMI cables are extremely finicky and carry gigabits per second at very low voltage levels. I've had a really hard time settling on one that's of adequate quality, finally buying a Hama one that's certified for a specific speed, but with age (after about a year) even those start showing glitches at high bandwidths.

SPDIF carries digital audio at kilobits per second. You will be fine with literally any sort wire. However, if you're running single-ended input and output, then ground loops might become an issue. So see to it that you're not.

With the distance you'll be running this at (probably no more than 30 cm), RFI/EMI will not be a problem at all. No need for an especially well shielded cable... it'll start mattering once your signal runs for over 100 meters.

So to put it otherwise, you should be fine with the cheapest cable you can get. Take it from an EE.

Now whether it'll /look/ good is another question. Personally I don't look at the back of my electronics that much :-)

RDavidson

  • Full Member
  • Posts: 2863
It is not about looks it is about audible performance improvements with better cables. I've owned Belden and Canare, terminated with studio standard Canare 75 ohm connectors (Blue Jeans Cables). I actually have them still sitting in the closet. Yeah, they indeed work fine and are inexpensive. They are a good baseline product. But I'm a curious person. I decided to try something better and the improvement in clarity and definition was clearly VERY CLEARLY audible even in my very modest system at the time. Do I know the science behind this? No. Does one need to be an EE to be a good listener? No. All that is required is normal auditory acuity, a willingness to experiment and try things for yourself, and the money to experiment. Often, cable dealers have demo programs, in which case you're maybe talking about the cost of shipping. What's there to lose?! It's your system. Try things. Listen. Educate yourself. It's the ONLY way to build a system you enjoy in your home.

cheater

  • Jr. Member
  • Posts: 23
What's there to lose?!

Time, money, effort, reputation. :-)

Jeff_From_Michigan

  • Jr. Member
  • Posts: 285
It is not about looks it is about audible performance improvements with better cables. I've owned Belden and Canare, terminated with studio standard Canare 75 ohm connectors (Blue Jeans Cables). I actually have them still sitting in the closet. Yeah, they indeed work fine and are inexpensive. They are a good baseline product. But I'm a curious person. I decided to try something better and the improvement in clarity and definition was clearly VERY CLEARLY audible even in my very modest system at the time. Do I know the science behind this? No. Does one need to be an EE to be a good listener? No. All that is required is normal auditory acuity, a willingness to experiment and try things for yourself, and the money to experiment. Often, cable dealers have demo programs, in which case you're maybe talking about the cost of shipping. What's there to lose?! It's your system. Try things. Listen. Educate yourself. It's the ONLY way to build a system you enjoy in your home.

Very well said, RDavidson!  I couldn't care less what anyone else thinks a cable could, should, couldn't or shouldn't do for MY system. When trying to discern a difference between different cables, I do what Judge Judy says: I put my listening ears on!

newzooreview

So you're trying to tell me a USB cable transmits an analog signal?...

Yes.

"Even though we tend to think of digital signals as being "binary" with just two possible states—high (1) and low (0)—changing instantaneously between them, this is not actually the case. The signal is an analog voltage." https://cdn.shopify.com/s/files/1/0660/6121/files/UpTone-J.Swenson_EtherREGEN_white_paper.pdf?v=1583429386

The waveform on the USB cable can be imaged on a USB oscilloscope:



https://www.testandmeasurementtips.com/measuring-universal-serial-bus-usb/

The receiver does not see the exact waveform that was transmitted. The receiver reconstructs 0s and 1s from the waveform. Because this is subject to errors, there is error correction built in to the USB protocol. This works well when timiing is irrelevent and the receiver at one end of the cable can request a new packet. However, the USB protocol uses isochronous tramsmission when timing matters. "Isochronous is for unreliable, time-critical data. In terms of defined USB classes it's pretty much just the USB Video (Webcams, etc.) and Audio classes." https://www.avrfreaks.net/forum/does-usb-have-error-correction-it

So, there is no error correction applied to timing-sensitive signals on USB (e.g. audio) and the receiver interpreting the ananog voltage into 0s and 1s will just drop the packets that it cannot resolve or will resolve them into the wrong value. A "packet," by the way, is just defined by the receiver according to a start and stop signal in the analog transmission. The "packet," like the 0s and 1s, is interpreted to exist.



rollo

  • Industry Participant
  • Posts: 5460
  • Rollo Audio Consulting -
  Go to the NORDOST website. They explain the myth and process of digital signal process. Not a Nordost dealer.


charles

stereoal

  • Jr. Member
  • Posts: 60
This ^ If you guys think an expensive cable can make 'zeros and ones' sound better, or that it somehow changes the bits... feel free to spend the money.


I used to believe this too until I put a $10 digital coax cable between my streamer and BDA-3. It sounded awful and made my ears hurt. I replaced it with a reasonably priced well-made NeoTech cable and the results were like day and night.

cheater

  • Jr. Member
  • Posts: 23
Hi all,

the quality of a cable is important in almost all digital cabling encountered nowadays. HDMI, USB, DVI, Ethernet, they all require vast bandwidths which are only achieved by ekeing out every single bit of analog bandwidth the cable has to offer in order to encode the digital data.

The same isn't true of SPDIF. The bandwidth of SPDIF is about a million times lower than that of HDMI or USB, give or take one or two zeros. You can run SPDIF through a wet sock and it'll be perfectly fine. The only thing you can do to it that's bad is buy a cable that's too esoteric, and will end up introducing capacitance that shouldn't be there, like some forms of coax. This can actually adversely affect the signal. Getting things this bad is astounding in and of itself, as a cheap cinch video cable like you'd get bundled with VHS players is enough to successfully transmit SPDIF without error. You really have to dig hard to come up with a design stupid enough to damage signal produced by SPDIF. Not even wet socks have enough capacitance to damage the signal like this, so that should tell you something.

DaveC113

  • Industry Contributor
  • Posts: 4344
  • ZenWaveAudio.com
Hi all,

the quality of a cable is important in almost all digital cabling encountered nowadays. HDMI, USB, DVI, Ethernet, they all require vast bandwidths which are only achieved by ekeing out every single bit of analog bandwidth the cable has to offer in order to encode the digital data.

The same isn't true of SPDIF. The bandwidth of SPDIF is about a million times lower than that of HDMI or USB, give or take one or two zeros. You can run SPDIF through a wet sock and it'll be perfectly fine. The only thing you can do to it that's bad is buy a cable that's too esoteric, and will end up introducing capacitance that shouldn't be there, like some forms of coax. This can actually adversely affect the signal. Getting things this bad is astounding in and of itself, as a cheap cinch video cable like you'd get bundled with VHS players is enough to successfully transmit SPDIF without error. You really have to dig hard to come up with a design stupid enough to damage signal produced by SPDIF. Not even wet socks have enough capacitance to damage the signal like this, so that should tell you something.

Lol, yes... and this is why coax sucks for the application. It's simply a convienience that 75 ohm coax cables exist, but it's a poor application for S/PDIF, and all coax S/PDIF cables are severely underperforming vs designs that are better for the frequency used.

twitch54

It is not about looks it is about audible performance improvements with better cables. I've owned Belden and Canare, terminated with studio standard Canare 75 ohm connectors (Blue Jeans Cables). I actually have them still sitting in the closet. Yeah, they indeed work fine and are inexpensive. They are a good baseline product. But I'm a curious person. I decided to try something better and the improvement in clarity and definition was clearly VERY CLEARLY audible even in my very modest system at the time. Do I know the science behind this? No. Does one need to be an EE to be a good listener? No. All that is required is normal auditory acuity, a willingness to experiment and try things for yourself, and the money to experiment. Often, cable dealers have demo programs, in which case you're maybe talking about the cost of shipping. What's there to lose?! It's your system. Try things. Listen. Educate yourself. It's the ONLY way to build a system you enjoy in your home.

and never discount 'expectation bias' !

twitch54


I used to believe this too until I put a $10 digital coax cable between my streamer and BDA-3. It sounded awful and made my ears hurt. I replaced it with a reasonably priced well-made NeoTech cable and the results were like day and night.

I think the point being made here is 'reasonably priced' ............

audioMirror

  • Jr. Member
  • Posts: 18
The whole "digital cable" debate has been going on for decades.

I don't know that any particular esoteric high-end cable is better than a Belden or Canare, but the possibility of a difference is based on a sound engineering foundation.

As some have said, the S/PDIF or AES/EBU signal is analog.  It is a digital stream on an analog carrier, but it is also the analog clock.  It is rare that any digital 1/0 errors will occur unless the cables are bad or too long (or not the right impedance), but the same can't be said for the analog clock.

Clock recovery is at the heart of much of the advances in DAC performance.  DACs now have what they call "reclocking", but it is never perfect.  Timing jitter makes a difference in the sound.  Also, everything in the digital chain (including the cable) can add RF noise within the DAC.

If digital cables can make a difference, then the transport also makes a difference.  The transport (except in asynchronous USB) has the master clock, and must have a good quality transmitter module that won't introduce timing jitter or noise.

RDavidson

  • Full Member
  • Posts: 2863
Time, money, effort, reputation. :-)

Exactly. :lol:
And I'm not a cable dealer, so I have no reputation to worry about. All that matters is what works best for me. Last I checked, there's absolutely nothing wrong with that. I'm only here to share thoughts and experiences.

YMMV Disclaimer : If I share info about my experience, it is just that and only that ; Anecdotal information to others. I would never expect anyone to take my word for anything I recommend without trying and learning on their own, particularly with audio gear, or food, or vehicles, or anything where people definitely have varying tastes. And guess how people arrive at understanding what they like or don't like? You guessed it! By trying things for themselves!!! Experimenting should be fun, even if you're on the hard-nosed science team :D

Regarding expectation bias, yes, that is a thing that can be pretty easily cleared up with A/B testing...unless you're one who simply believes more expensive or looks nicer = better. I'm definitely not of that mindset. I wish the old Belden wire performed as well (to my ears in my system) as the Stereovox, but it doesn't. It'd have saved me some money if so, but it didn't. I apologize if my cable choices and spending monies offended anyone as I work to improve my personal audio pleasure haven. :lol:

Have fun folks!!! AND don't let others discourage you from having fun!!!