Audio/Digital Cables

[tuga]

What are those technical reasons? How have they been demonstrated to cause audible differences?

I would expect that an old transport into an old DAC to produce audible levels of jitter, more or less depending on the cable used (f.ex. a 50 Ohm vs a 75 Ohm cable). I think that I was able to some 30 years ago when I bought my first 3-box CD playback system.


With different coax cables into a modern DAC with a reclocked S/PDIF input (f.e. Benchmark DAC) I doubt it would make a difference.

 

[mindlagoon]

What they are not considering is that you can't actually send a number down a cable. It has to be transformed or coded into and electrical signal, which is effectively a wave form and is therefore subject to possible distortions during transmission. Or during encoding/decoding.

Yes, but the waveform your refer to is merely a symbol representing a bit or group of bits, e.g a voltage level, a frequency, a phase, or a change in one or more of these. The symbol set and the distance between the symbols (the Hamming distance) is selected according to the medium and the expected SNR.

 

[tuga]

Yes, but the waveform your refer to is merely a symbol representing a bit or group of bits, e.g a voltage level, a frequency, a phase, or a change in one or more of these. The symbol set and the distance between the symbols (the Hamming distance) is selected according to the medium and the expected SNR.

I wonder if you mean this? Any good ol' DAC should be able to provide clean levels. And yet...

Audio Note DAC2.1x Signature

https://www.stereophile.com/content...t-dac-21x-signature-da-processor-measurements


Benchmark DAC3

https://www.stereophile.com/content...preamplifier-headphone-amplifier-measurements

 

[Robert]

Went shopping last week to Sainsburys, bought some Heinz baked beans and carried them home in an Aldi poly bag. They tasted ok but nowt special. Did another shop this week. More beans but this time I carried them home in a Waitrose bag. They tasted amazing.

One should always go cable shopping with a Waitrose carrier bag, or you could really push the boat out and go Fortnum and Mason

 

[Curtis]

One should always go cable shopping with a Waitrose carrier bag, or you could really push the boat out and go Fortnum and Mason

Don’t forget a coolie bag if your getting cryogenically frozen cables!

 

[Del monaco]

In ma

Don’t forget a coolie bag if your getting cryogenically frozen cables!

and plenty of ice cubes in their so they don’t thaw out!

 

[Jim Audiomisc]

Yes, what I'm alluding to is that many people have a perception that digital means numbers and is therefor immune to error, as the numbers at one end will be identical to the numbers at the other.

What they are not considering is that you can't actually send a number down a cable. It has to be transformed or coded into and electrical signal, which is effectively a wave form and is therefore subject to possible distortions during transmission. Or during encoding/decoding.

Yes. And one of the major advantages of digital systems is the ability of the RX to correct for or remove signal pattern distortions, so they don't change the 'numbers' they are being used to convey. That's why it is unlikely that most reasonable choices of coax cable are unlikely to alter the series of values emerging from something like and SPDIF receiver. Of course, nothing is invulnerable to being poorly designed or faulty. But that may tell us more about the RX than the cable.

 

[Jim Audiomisc]

If the designers of equipment supply a coax rca connection rather than bnc then they can’t be that worried of a true 75ohm connection.
The spurious chit that cable companies, mags & retailers spurt out about needing “digital coax cables” is a disgrace.

And in the real world, no coax or transmission pair I've ever encountered is truly 75 Ohms from DC up. cf the Heavyside Condition. Most cables simply don't have the required shunt conductance / length. Fortunately, near DC with most domestic links this simply doesn't matter, because the lengths are short.

 

[Jim Audiomisc]

I wonder if you mean this? Any good ol' DAC should be able to provide clean levels. And yet...

Audio Note DAC2.1x Signature

https://www.stereophile.com/content...t-dac-21x-signature-da-processor-measurements


Benchmark DAC3

https://www.stereophile.com/content...preamplifier-headphone-amplifier-measurements

My impression simply looking at those plots is that they largely show the noise level at the DAC's analogue output. Plus perhaps the first example having the DAC dithering rather more than the Benchmark. (Translation: The first example adds more noise.)

Beyond that, for the Benchmark it just shows what happens when you failed to dither the samples in the first place. Not sure if it says much about 'cables' though. Am I missing something?

 

[tuga]

My impression simply looking at those plots is that they largely show the noise level at the DAC's analogue output. Plus perhaps the first example having the DAC dithering rather more than the Benchmark. (Translation: The first example adds more noise.)

Beyond that, for the Benchmark it just shows what happens when you failed to dither the samples in the first place. Not sure if it says much about 'cables' though. Am I missing something?

I was looking for an image which would show the voltage levels, and how the representation of the data in the analogue domain could be somewhat affected by noise.

 

[Martin M]

Jim, both plots are undithered. Just that the AN is not a 'classically good' implementation whilst the Benchmark is superb. Neither has anything to do with analogue noise on a cable.

 

[notevenclose]

Jim, both plots are undithered. Just that the AN is not a 'classically good' implementation whilst the Benchmark is superb. Neither has anything to go analogue noise on a cable.

I wonder which one sounds best?

 

[tuga]

Jim, both plots are undithered. Just that the AN is not a 'classically good' implementation whilst the Benchmark is superb. Neither has anything to go analogue noise on a cable.

It doesn't. That wasn't clear in my first post.

 

[tuga]

My impression simply looking at those plots is that they largely show the noise level at the DAC's analogue output. Plus perhaps the first example having the DAC dithering rather more than the Benchmark. (Translation: The first example adds more noise.)

Beyond that, for the Benchmark it just shows what happens when you failed to dither the samples in the first place. Not sure if it says much about 'cables' though. Am I missing something?

In case you are interested, Robert Harley explains the test here: https://www.stereophile.com/content/quality-lies-details-page-6

 

[Linnovice]

Well, if I can wade my way through this sea of sceptism, I’m back again cos the cables arrived today, a day early. I will start by reiterating my earlier statement. I know very little about digital audio and do not have any preconceived ideas. That’s why I asked you lot!

First up I swapped out a URM 76 SGC E coax cable for the Chord C Digital both about .5m long. I can’t say it knocked my socks off but it was different. The top end sounded smoother somehow but in truth not a case of night and day. Next up I swapped out the joined usb cable for a 5m Neo d+ a ~ b usb. That was definitely night and day difference. The sound is much smoother and the stage seems wider.

Now, if I was reading this a few weeks ago I would have labelled it B S! At this moment in time though my ears are telling me something else. These cables have definitely improved the sq and couple with the V-Link it’s nudging the sq of my analogue system. It’s a much more comfortable, natural listen and less tiring. I know that all sounds bxs but I’m not kidding myself. I don’t understand why though so now you can all shout at me and tell me I’m imagining the improvement.

I’m going to listen tonight and try the previous cables again tomorrow.

 

[tuga]

Well, if I can wade my way through this sea of sceptism, I’m back again cos the cables arrived today, a day early. I will start by reiterating my earlier statement. I know very little about digital audio and do not have any preconceived ideas. That’s why I asked you lot!

First up I swapped out a URM 76 SGC E coax cable for the Chord C Digital both about .5m long. I can’t say it knocked my socks off but it was different. The top end sounded smoother somehow but in truth not a case of night and day. Next up I swapped out the joined usb cable for a 5m Neo d+ a ~ b usb. That was definitely night and day difference. The sound is much smoother and the stage seems wider.

Now, if I was reading this a few weeks ago I would have labelled it B S! At this moment in time though my ears are telling me something else. These cables have definitely improved the sq and couple with the V-Link it’s nudging the sq of my analogue system. It’s a much more comfortable, natural listen and less tiring. I know that all sounds bxs but I’m not kidding myself. I don’t understand why though so now you can all shout at me and tell me I’m imagining the improvement.

I’m going to listen tonight and try the previous cables again tomorrow.

Have someone else change/swap the cables without your knowledge sometime this week.

 

[Heckyman]

Hi all. I’ve recently acquired a Musical Fidelity V-Link192 usb to coax converter. I bought it from a fellow pfm member and I’m very very pleased with it. I use it on the usb out from an iMac to the coax in on my Teac UD-H01 DAC. I am now seeking advice on upgrading the relevant cables. I need a 3m usb a to b cable plus a .5m coax to coax digit cable.
My knowledge of digital audio is limited and as with analogue interconnects there is a lot to choose from. What are the recommendations that you would make please? I need to keep the cost within reasonable limits but am prepared to pay around £150 all in.

Presumably you have some basic cables already?

Having spent a few hundred quid on USB/co-ax cables AND owned a V-Link mk1, if you have a budget of £150, I would wait a bit and upgrade the V-Link (or its PSU) before spending anything on cables.

 

[Linnovice]

That’s a good idea but may be difficult to achieve. The only other person in the bubble at present is my good lady. Expecting her to grovel around behind my kit and make changes without me seeing would be like expecting Inspector Clouseau to solve the crime.

 

[Heckyman]

..ah just read that you've already got the cables!

Well, Oyaide is a solid choice, one of the few companies who actually make their own cables and connectors.

I have a couple of their cables at different price levels.

 

[Linnovice]

The V-Link is powered by the usb supply. I set it up originally with standard cabling and the original question regarded modestly upgrading the cabling. Which, is what I’ve done.