ISO Regen performance Improvement Cheap!

[marce]

On 5/30/2018 at 1:48 AM, JohnSwenson said:

My current ideas as to what matters for a DC cable is inductance and dielectric absorption. The inductance is primarily determined by the geometry of the wires, and dielectric absorption is determined by the insulation on the wires.

 

 

 

John S.

John,

I cannot see how dielectric absorption can have any effect at DC... Even low frequencies it has minimal effect at DC it will have none? Puzzled.

[marce]

2 hours ago, lmitche said:

Do either of you have another idea or explanation as to the cause of the positive impact of these various DC and network cables on sound quality observed here?

Well it definitely is NOT dielectric absorption, it is a high frequency ac issue, the main thing being ac not dc as we are discussing with these cables. Sorry but we can't ignore physics. 

[marce]

10 hours ago, Abtr said:

Could a passive filter with capacitors and inductors reject common mode noise?

A common mode choke can very effectively....

 

[marce]

A few links and a screen shot of my EMC folder from my collection of electronic based data, should provide plenty of information regarding EMC....

http://www.hottconsultants.com/pdf_files/APEC-2002.pdf

http://www.analog.com/media/en/training-seminars/tutorials/MT-095.pdf

https://www.edn.com/electronics-blogs/anablog/4309627/EMC-RFI-SI-consultant-Henry-Ott-has-a-new-book

http://www.hottconsultants.com/pdf_files/aug-ptk.pdf

http://www.compliance-club.com/archive/keitharmstrong/design_techniques1.html

https://incompliancemag.com/article/complying-with-the-eus-emc-directive-without-3rd-party-testing/

http://www.vicorpower.com/dc-dc-filters/qpi

 

[marce]

2 hours ago, opus101 said:

 

A possible reason (just conjecture at present) is that the longer the cable, the better it is at being a common-mode choke. But I can't help thinking that a dedicated CM choke will do considerably better than an ethernet cable.

 

Has anyone tried battery powering the IR to see if the improvements exceed the gains with the cat7 cable? That might shine more light on what's going on here.

Slapping a scope on the end of the various wire configurations would be a better bet.

[marce]

15 hours ago, Abtr said:

Thanks. But for an ethernet cable to function as a common mode choke filter, POE should use the two wires of a twisted pair for DC power and return connections, i.e., solid colored wires for (positive) power and dashed white wires for (negative) return. The POE adapters don't do this. As @mansr stated above, they connect both wires in one differential pair to the negative side and both wires in another pair to the positive side of the DC power supply.

 

So, it seems that most mechanisms thought to be at work in tightly twisted pairs (e.g., common mode noise rejection, impedance matching of the two conductors which helps common mode noise rejection, reduction of inductance and inter-wire capacitance) don't apply to POE.

 

Perhaps the twisting of two conductors for each DC connection cancels out the magnetic field that a single wire would generate around itself, thus preventing it from inducing noise into the other twisted pair and/or other audio gear. I wonder how relevant this can be for a DC power cable/connection?

Slap the cable through a ferrite and you have a common mode choke...

[marce]

15 hours ago, Abtr said:

Thanks. But for an ethernet cable to function as a common mode choke filter, POE should use the two wires of a twisted pair for DC power and return connections, i.e., solid colored wires for (positive) power and dashed white wires for (negative) return. The POE adapters don't do this. As @mansr stated above, they connect both wires in one differential pair to the negative side and both wires in another pair to the positive side of the DC power supply.

 

So, it seems that most mechanisms thought to be at work in tightly twisted pairs (e.g., common mode noise rejection, impedance matching of the two conductors which helps common mode noise rejection, reduction of inductance and inter-wire capacitance) don't apply to POE.

 

Perhaps the twisting of two conductors for each DC connection cancels out the magnetic field that a single wire would generate around itself, thus preventing it from inducing noise into the other twisted pair and/or other audio gear. I wonder how relevant this can be for a DC power cable/connection?

Second reading a cable cannot act as a common mode choke! As siad use a ferrite on the cable.

[marce]

9 hours ago, opus101 said:

 

Why? You reckon a scope can resolve CM noise differences?

No but its the only way to determine what if anything is going on... I am not a believer in magical cables either dc or ac.

[marce]

On 6/8/2018 at 1:04 AM, totoxio said:

Question: Are dielectric absorption and insulation resistance the same or related?

 

Mr. JS mentioned something about dielectric absortion as one of the possible causes for this POE discovery. After that, marce replied "

"John, I cannot see how dielectric absorption can have any effect at DC... Even low frequencies it has minimal effect at DC it will have none? Puzzled".

 

These CAT cables strands are very thin, and proportionally, the insulation is higher (maybe). The cheaper CAT cables also use PVC as insulation material. So maybe there's a lot of insulation resistance going on. Combining both posts (and yours), maybe there's some atenuation going on for AC leakages because they travel in the outside layer of the CAT cables by skin effect, closer to insulation than the DC. So, more resistance to AC than to DC, so AC filtering.

 

Maybe I'm saying nonsense, but hey, it's just another theory.

DA does not have any effect at dc or low frequency ac.

[marce]

31 minutes ago, Solstice380 said:

 

What happens with current spikes?  Don’t they have some higher frequency component / behavior that could be affected by dielectric absorption?

look up dielectric absorption, its irrelevant for what is being discussed.

[marce]

52 minutes ago, Solstice380 said:

 

Sure.

100% sure... The microwave and rf engineers I was with last week were more than sure, I asked their opinion just to double check my understanding of DA... As were many others I have asked...

Its a DC supply cable, nothing special as long as it is specified for the job in hand, electronics is full of them, the magic ones only appear in consumer audio, I wonder why!!!

[marce]

How... How can a DC cable have such an effect on the sound?

[marce]

1 hour ago, sandyk said:

 I didn't say that he did.

Both Mansr and Marce have a history of ridiculing numerous confirming reports on this and other subjects in other areas of the forum, even when a high profile E.E. says similar.

Sandy I ask for explanations of what is going on, I don't blindly follow the crowd, there is a difference.

There is also the fact that I don't see magic cables (or claims) other than on these sort of sites or audio cable manufacturers often totally BS marketing information or white papers, one has to wonder why.

[marce]

So provide some explanation of how a DC cable can have such an effect on the sound quality.... an effect that I would have to use a DSP to mimic.

[marce]

47 minutes ago, bit01 said:

Nothing wrong with being the skeptic but I wish you could try it and listen for yourself. You might or might not hear any differences. If you ever do please do share your experiences and any science you might think about!

ATB.

Over the years I have tried all this stuff as well as measurements in the past, funnily when I stopped trusting my ears my system improved....

By the same token bring some explanation and measurements to the discussion to prove to yourself and others that the sound changes are all in the mind.....

As said I don't see magic cables in other areas of electronics only in Audiophile audio...

And yes cable differences are measurable, many are far below the threshold of hearing and to have the effects many report the differences will be easily measured.?

[marce]

34 minutes ago, totoxio said:

Yeah I vote for an open minded approach to this CAT for DC discovery. It is very advisable to first listen, not for an hour or two, but at least for a week. My skeptical half says there is an explanation, we just don't know it yet.

Discovery... Nope not without LOTS of empirical data to back it up, a few hearsay comments do not a discovery make. LOL

Its a cable carrying DC it is not an active component, it has some parasitic resistance, capacitance and inductance and it is working at DC.....

[marce]

6 minutes ago, genjamon said:

 

What exactly is causing which effects - now that's a good question.  And many ideas have been posited on this thread.  We won't be able to do anything more than this silly game of trial and error unless someone with skill and tools actually properly tests systematically for the effects of geometry, shielding, dielectric, etc on rejection and/or filtration of electrical interference.

Cables funnily enough play a big part in electronic signal transmission, loads of information out there on cables and signal integrity, a good start would be the work by Oliver Heaviside...

[marce]

10 hours ago, RamDawg said:

Troll

Pathetic... \Just resorting to name calling instead of taking part in an open debate...

[marce]

Its getting like that on just about every thread, you have a differing view or question how something could happen and your jumped on as a troll as a recent thread has highlighted... It a sad reflection on the hobby when we can't have differing views...

Quote

Experiment with the various inexpensive DC ethernet cables first then your perspective will be legitimate. That's all. Trolls are ones who've not yet done so, put their 2 cents in and make assumptions based on no experience.  

Then you get comments like the one above, just makes me laugh, my experience of DC cables etc. makes me far more qualified than the poster to comment on such things, yet my views will be slagged of as a troll because they are at odds with all those that believe in magic dc cables.

[marce]

3 hours ago, bit01 said:

As for the DC -ve coax: I would try copper rather than copper clad steel, with as thick a wire as possible to minimize ground plane modulation

could you explain as it is DC...

[marce]

6 hours ago, Speedskater said:

Well the Copper Clad Steel (CCS) wire is easy. It's a poor choice for anything much below 100MHz.

But then we get to the 'ground plane modulation' part, I too await an explanation.

copper clad steel co-ax is generally used where you need to pull the cable and are carrying a HF signal such as cable TV.

 

[marce]

15 hours ago, Cornan said:

Watching this https://terpconnect.umd.edu/~wbreslyn/magnets/index.html I in combination with my own experiences with DC cables I wonder if the force of the eddy currents could possibly define the different audioble frequencies heard with different wire materials?As seen on this website copper makes a magnet fall slow. Could the slow movement of electrons define bass and low end midrange while a faster movement of electrons defines (for example silver) high midrange and treble? Just a thought. What is your opinion @marce, @jabbr and @sandyk?

 

If this is plausible I will surely continue to try pure silver on +Ve and pure copper with copper shield (JSSG) on -Ve. It would surely open a lot of doors for experiments.

Drift Velocity:

https://en.wikipedia.org/wiki/Drift_velocity

http://resources.schoolscience.co.uk/cda/16plus/copelech2pg3.html

 

[marce]

On 6/25/2018 at 5:15 PM, BigGuy said:

Do we have a theory as to why the addition of a Kemet, etc., across the v+ & v -  could have such an effect?

Yes its acting as a decoupling capacitor....

[marce]

15 hours ago, mansr said:

Obviously. The question is how bad the downstream regulators need to be before the addition of an external capacitor makes an audible difference. If a £0.15 capacitor provides such a whopping improvement, why didn't the manufacturer include it in the design?

I do keep saying that in reality the whole power delivery system should be considered, from main supply to device power pins, for any sort of circuit analogue or digital, with digital often being more problematic because of the high initial current draw, so the decoupling is as critical as the main supply, if not more so. Whereas as audio frequency analogue the main supply plays a big part, though local decoupling is still required. 

[marce]

12 hours ago, Abtr said:

It seems that a polymer aluminum capacitor (e.g., Kemet A750) across DC input may improve SQ by DC buffering/smoothing, shunting AC noise (decoupling and bypassing), and fast transient response to load change. I will try it with my active crossover boards and if that works one might ask why such a simple, cheap and obvious tweak isn't implemented as standard in all audio equipment?  

Most equipment is designed with decoupling capacitors on the board, it would have to be a bad design not to have any, the whole power delivery system is critical...