Difference in sound between copper and silver digital cables?


Is there a difference in sound between copper and silver digital cables, or purely in the implementation?
pmboyd

Showing 13 responses by williewonka

I tried an experiment a few years back...
- I built an extremely good digital cable with silver signal wires and exceptional RCA plugs
- I then "stepped back" the design by replacing the signal wire with copper - there was no change
- I then stepped back the design once more opting for a more affordable RCA plug - again there was no change.

The geometry of the cables is an advance Helix design, so that probably made a significant contribution to the performance of the cable.

The RCA’s finally used are silver coated copper, KLE Innovations Silver Harmony RCA and the copper wire was from Neotech.

With this design using a silver conductor seemed to offer no advantage.

With other geometries there may be some benefit to using silver conductors

Hope that helps - Steve
@david_ten - Ooooops sorry about that….
@williewonka Steve: within the parameters of (the "experiment" / components / systems) you tested them, correct? Thanks.
Yes - I was testing with digital audio files up to and including 24/192. They connected a Schiit Bifrost DAC and a Musical Fidelity V-Link192 USB-S/PDIF Converter and an Apple PC as the source of the digital files via USB.

The amp was a NAIM 5i Mk II and the speakers are the Gershman Acoustics Sonogram model

I could not discern any degradation in audio quality at those sample rates, higher sample rates may have issues, but I am unable to test ot those rates.

I did drop down to the copper Harmony RCA and there was also no degradation, but I the silver plating on the copper harmony may wear off after 30 insertions, so I do not use them for anything.

My Silver Harmony RCA’s had been inserted around 40 times to that point without wearing to the copper underneath the plating. But this very much depends on the quality of the socket they are plugged into.

For all analogue cables I only use Harmony Absolute RCA’s

Hope that helps

@almarg - I too wondered about this aspect of digital cables design.

It all started about 5 years ago when KLE Innovaitons contacted me about their products.

I built a very good analogue cable and wondered  how it would perform in the digital realm - so I simply tried it and  it worked great.

I contacted Keith Louie Eichman and we exchanged several emails on the subject. But although he assured me that his RCA's are perfect for digital application because of their impedance, he would not reveal the actual impedance. So I am unable to comment on this aspect in any further detail.

Apparently - they work extremely well with 50, 75 and even 110 ohm applications.

After a lot of reading from the web - could it be possible that the impedance of the RCA only has to be greater than 50,75,101 ohms? 

Perhaps it is the design of the actual RCA ?
 i.e.the neutral connection is very small compared to other RCA's 

I have tried a few different KLE Innovations RCA's in digital applications  and they all worked extremely well.

Sorry I could not provide more details - Steve


@almarg - Al, thanks as always for you complete and thorough descriptions and reasonings.

Your point about... 
one "Wire Type" being optimal for 50, 75, and 110 applications.
It was the RCA connectors I was referring to as being suitable for those impedances and not the wire type. But I do understand that according to conventional wisdom,  the impedance of the RCA should match the cable - so I too, wondered how one connector could be used for all three impedances.

However. Keith Louie Eichman has been delving into the minutia of the science of cable and connector design for over 30 years and has far more knowledge than myself, so I have no reason not to believe his assertions about his RCA connectors. 

The only tools I have to test their performance is my ears and to me they sounded better in every way.

The geometry of my cables is a signal wire inside a helix coiled neutral wire and unfortunately I have no idea what the impedance of that cable might be.  But perhaps it is the cable geometry that is performing "the magic" here? 

My I first attempt at making a cable for SPDIF purposes used some wire from a piece of CAT6 Ethernet cable and Copper Harmony RCA's using the Helix geometry. The signal wire was a single CAT6 wire and the Helix neutral was a twisted pair.

My "point of reference" for the comparison was a commercially available 75 ohm 1 meter cable specifically designed for digital transfers from Van den Hul, that had the requisite 75 Ohm RCA's. This was a conventional Coax geometry.

The results even surprised myself - that simple little CAT6 cable provided significantly better performance than the Van den Hul product.

I do not claim that my Helix geometry, with the KLEI RCA's,  would work for any length of cable, since my interconnects, as tested, were only 3 ft long.

The set of cables I finally ended up keeping in my system were only 18 inches long. Which also seemed strange since, from what I have read on this forum,  a digital cable should be over a certain length in order to work at it's best..

But I did compare the 3ft to the 18 inch cable and found no difference

Others have tried my Helix design as a SPDIF interconnect on longer cables,up to 3 meters, and they claim to have had similar success. 

There are many out there that do not believe the claims I have made regarding the Helix Cables and the Harmony RCA's in my many postings on this forum. 

And - if I hadn't tried them for myself, perhaps I wouldn't believe those claims either.

But there are now dozens of people from around the world that have tried them and reported significant improvements in sound quality.
- So it is not just my ears that is hearing the improvement

Regards - Steve





Because the OP was asking specifically about copper vs. silver would be my guess.

But you could start another thread just for that :-)


RE: ...
All you need is to have every send bit being received correctly
And there lies the problem !!!

My understanding is...

With SPDIF, Optical and USB there is no way to know IF the data stream RECEIVED is identical to the data stream SENT

Ethernet is different - data is sent in "packets" together with a CHECKSUM - if the CHECKSUM calculated from the packet received is not the same the checksum sent with the packet - then the packet is resent until it matches. 

So - if there are errors in the SPDIF, Optical or USB data stream - the erroneous values are NEVER detected and hence, "interpolated" by the DAC to a best approximation of what was sent.

So apply these "Approximations" to L and R channels and what will often result is a phase differences between the channels, which will alter the image, change dynamics and degrade the overall sound

So getting a GOOD SPDIF, Optical or USB cable actually DOES improve  sound quality.

Regards - Steve  


@danip4 - I’m far from an expert on this topic, but this thread appears to show Checksum’s are employed in Ethernet...

https://networkengineering.stackexchange.com/questions/37492/how-does-the-tcp-ip-stack-handle-udp-ch...

What I can confirm is that using Ethernet, conveys a significantly better audio result than any of my asynchronous mode transfers i.e. USB, SPDIF or Optical. Each of those required the best cable possible to even approach the same levels of sound quality that Ethernet provides.

So I think my point still stands - the quality of sound from a digital source that uses asynchronous transfer protocols can be impacted by the quality of the cable used

Regards

@danip5 - you are clearly far more knowledgeable in this area than myself, so if I could impose on you one last time, for some points of clarification...

If I understand your posts correctly -
"Ethernet" detects errors, but it does not request a re-transmit - it just identifies if the packet should be "dropped/blocked"

Whereas TCP/IP "can" notice the data loss, but...
- is retransmission something that is "programmed" using TCP/IP ?
- or is retransmission automatically taken care of by TCP/IP ?

The reason for this point of clarification is
- if re-transmission has to be programmed - then it really depends on the TCP/IP implementation approach, from one Ethernet connected device to another, as to how good each would sound.
- Whereas, if it is automatic, then all Ethernet connected devices should be able to perform to a "similar level".

Also - Is my understanding of SPDIF, optical and USB methods of transmission correct...
- i.e. if data is lost/corrupted, it goes undetected and a DAC will simply try to re-create the audio signal from the digital stream received as best it can ?

It is also quite clear from your posts that Ethernet is far more reliable at successful data transmission than either SPDIF, optical and USB methods. Which would account for the superior sound I now enjoy from my Bluesound Node 2 - which uses an Ethernet connection

Many Thanks for your patience - Steve









@danip - all good :-) 

Many thanks for taking the time to explain.

Regards  - Steve
Wig, many thanks for the Kudos - It's always nice to hear of someone else that is enjoying better sound due to the Helix geometry.

I've had many conversations with people about the various digital sample rates when used with the Helix SPDIF - and I (and others) have found that 16/44 provides exceptional sound quality, to the point where it becomes difficult to tell the difference between 16/44 and 24/192 formats.

Unfortunately 24/192 is as high as I am able to decode, so I have no idea what the maximum sample rate the Helix SPDIF is capable of conveying.

I'm hoping someone on Agon that uses sample rates higher than 24/192 might give the Helix a try :-)

Thanks for having the courage to take the plunge into the "Helix Pond" - I'm pretty sure you will also really enjoy the analogue Helix cables also .

If anyone else would like to try building them, take a look at
http://image99.net/blog/files/54c02c12532d31f960ee85a6ed674b01-83.html

Click on the link for the interconnects on that page and then scroll down to (or search the page for)  …
"Can this cable be used for SPDIF purposes?"
It details the wires and RCA's I have found to work extremely well for digital purposes

Regards - Steve
@maxima95 - I have only tried this for SPDIF cables up to 2 meters long. Others have tried it for SPDIF up to 3 meters long.

AES3 (also known as AES/EBU) is a standard for the exchange of digital audio signals between professional audio devices.

I have only tried Helix cables up to and including 24/192 for SPDIF cables between a USB interface into a 24/192 DAC

I do not know what sample rates Professional Audio Devices work at, but I would have to assume sample rates much higher.

I would think that the Mundorf XLR style cable would be able to support much higher rates, but to date nobody has tried that design in the digital realm.

Duelund is very good for analogue, but that has more to do with the cotton/oil insulation.

Before spending lots on the Mundorf wire - I would try using the cryo-treated...
- the 24 gauge silver plated Mil-spec wire/Teflon for the signal
- and 20 gauge silver plated Mil-spec for the neutral

Also, I would increase the ratio of neutral:signal to 4:1 or even 5:1 to increase Helix coverage for higher sample rates

Other reasons for trying the lighter gauge mil-spec in place of 20 gauge Mundorf or Duelund
- smaller gauge wires are less prone to RFI/EMI - I just tried a 28 gauge wire for a phono cable I am prototyping and the hum significantly reduced as the gauge got smaller - I compared it to using the 20 gauge Duelund, signal wire which hummed a lot.
- also, early tests of the RCA plugs revealed that using the higher grade Pure Harmony and Absolute Harmony plugs (which have better IACS ratings, provided no additional benefits over the lower grade Silver harmony RCA,
when used for SPDIF cables.

I have not personally tries any XLR connectors either, so I cannot recommend a specific type or brand
- based on my experience with other connectors I would have to assume silver plated copper pins would offer the best results

Sorry I could not provide better info, but I stopped using/developing SPDIF three years ago when I replaced my USB-DAC setup with a all-in-one Ethernet streaming device.

The photo’s of the XLR cables are analogue cables and courtessey of a fellow DIYer in Bulgaria that developed them and reported extremely good sound quality.

I hope that helps - Steve
@maxima95 - unfortunately XLR implementations are not my specialty, since most of my components do not employ that socket type.

Others have had great success using the Helix geometry with Analogue cables, but I do not know of anyone that has tried what you are considering.

If I were in your position, I would try building a prototype cable first using inexpensive wire.

For prototyping I used...
- Thermostat wire (for the Helix neutral) from a local hardware store  
>>> Thermostat wire is 18 gauge solid core copper
>>> it holds the helix shape very well 
- CAT6 for the signal wires - 24 or 28 gauge is ok

The prototype wire for a 3 ft AES/EBU digital cable would probably cost less than $20 - since you already have some good plugs. 

If the cable sounds good then opt for the better grade wire.

What I have observed with digital cables is that wire quality is not as important as it is with analogue cables, so I would use 20 gauge silver plated Mil-spec for the neutral and 24 gauge mil-spec for the signal.

Hope that helps - steve


" Copper tends to deliver more mid-bass body and weight and is not as well defined in terms of leading edge detail. Bass is a tad more rounded and yes this can vary, but in general is accurate."
I’m not disagreeing with this statement - but I do have some thoughts...

I have been dabbling with cables for the last 12 years. in that time I have read many postings on Agon pertaining to what people hear with their various cable selections and substitutions.

Being a firm believer in trusting my ears I have to believe this statement is true - i.e. it is what those people observed.

Cables are very complex beasts...
- wire type - solid or stranded
- metaurgy - copper or silver plate or silver
- insulation type and thickness
- cable geometry - how the wires are placed with respect to each other within the cable
- burn-in
- directionality
- etc...

But one thing I have noticed in the last 12 years...
- cables effect the performance of the connected components.

So it might not be the cable that is actually responsible for changing the sound/tone to "more mid bass body", it is just the component performing differently ...
- due to the various attributes of the cable.
- and the cable is simply conveying what the component is now delivering

Regards - Steve