ISO Regen performance Improvement Cheap!

[wushuliu]

You guys must have missed my post in the main thread where I already opened up several different cables to inspect, including IBRA, Vandesail, and Amazon Cat7s. The IBRA was the WORST of the bunch in terms of build quality. The individual shielding is half-assed, the mesh braid felt so light and thin I thought it was fake. I laughed when I cut the thing open. Hell *I* could make a better cable with one hand. And scotch in the other. 

 

The cable with the best build quality was the Amazon. Night and day. It had the best internal construction of the lot; Multiple layers of shielding; proper and *tightly* wrapped. Thick jacket. It was the most difficult to peel apart. I was kind of surprised. I almost wonder if Blue Jeans Cable or Belden makes it. It had that kind of feel and quality of materials.

 

And yet it didn't sound as good as the rest. Or I should say, it sounded good but in a different way - a way that more aligns with one expects from superior shielded cable: Neutral, almost bland sound quality, Good micro detail, and what seemed like a little bit lower noise even. But it lacked the flowing, organic presentation of the IBRA. No question. Lacked presence. Maybe that would improve with time though, I don't know. I could see some people preferring it.

 

So if you really want to test the shielding theory, get the Amazon Cat7 and compare. The IBRA as quality shielding/build though... don't think so.

[wushuliu]

49 minutes ago, sligolad said:

We should be careful when lumping cable shielding under one brand since my experience after opening a flat IBRA CAT7 it had really good shielding on the pairs. The foil was really heavy and coated and it took a bit of work to open it.

I will open one of the round IBRA CAT7 cables i have to see how good it is.

 

I did not get the flat IBRA, but I would be very, *very* surprised if its shielding is as good as say, the Amazon. The flat Vandesail I opened up certainly was not that impressive. Being flat, it can't have had the same layers of shielded as some of the round ones. The Amazon has a quality outer copper shield, an outer foil, and then very, very tightly wrapped shield around each twisted pair (may be more but I don't remember - see my post at USAmart). Shielding is not the reason for what we are hearing. And there is a large degree of variation between brands. I suggest you guys get a bunch of different cables, both flat and round and open them up, like I did, and you'll see what I'm talking about. 

[wushuliu]

1 hour ago, charlesphoto said:

Overall more natural and analogue sounding, but def. not the repeated exclamations and fist pumping change as seen by Tubelover. 

 

 

It may help to actually do what he did. Although interesting, you did something completely different.

[wushuliu]

2 hours ago, Superdad said:

Gauge, shielding, and topology--that's what it always comes down to with cable.  

 

 

Except in this case it seems that the poorer the CAT7 construction, the better the result. 

[wushuliu]

As a side note it came to me that the only other Ethernet cable I've come across with the same look, feel, and build quality of the Amazon is Blue Jeans Cable. And guess where BJC is located...

[wushuliu]

3 minutes ago, charlesphoto said:

We’ll see. I just ordered a meter of Supra 8 to compare to the Monoprice I’m using (it is blue inside the inner wire foil). Supra sold by someone here in Seattle so should get it quickly. 

 

Why not just order an IBRA or UGreen (round) as well to have as the point of reference? Should get to you in the same time as the Supra and it's just a couple bucks. No one else has used Monoprice or the Supra in this application that I'm aware of. 

 

 

[wushuliu]

16 minutes ago, charlesphoto said:

I had an IBRA and then returned it. Wasn’t anything that special or different compared to what I had on hand (the Monoprice, Teragrand, AQ Cinnamon, etc). I think these were picked out of a hat solely because of their availability on Amazon. Lots of Cat 7 to choose from out there. So having compared the monoprice with the IBRA when I had a poE I think I have a pretty good idea of how to gauge the Supra. 

 

I didn't see you mention having used any of those in this application, only the Monoprice.

[wushuliu]

6 hours ago, charlesphoto said:

Turns out the ebay Supra seller lives in the neighborhood so he dropped  the meter of CAT8 on my porch.

 

Mine arrived today as well. Thanks for the quick report. Sounds promising.

[wushuliu]

Here are the specs for the Supra:

Technical Info

Cable design

Cable	4 pair, Cat 8 S/STP PIMF
Lead area	0.23 / 26	mm2 / AWG
Number of strands	7	pieces
Lead material	Bright drawn oxygen-free 5N copper
Insulation	Air-injected, low capacitance PE
Inner shield	Aluminium foil
Outer shield	Tin plated, oxygen-free 5N copper braid
Jacket	PE (FRHF)
Outer dimension	Ø 6	mm
Flame retardancy	Yes

Electrical performance

Resistance	145	Ohm / km
Capacitance	43	pF / m
Bandwidth	2,000	MHz
Skew @ 100 MHz	5 / 100	ns / m
Impedance	100	Ohm
Velocity factor	0.8x	C (speed of light)

----------------------------------------------------------------------------------------------------------------------------------------

Internal geometry doesn't seem all that different from the other round cables. However, one aspect to be considered is twist rate. The twist rate increases from Cat5 to Cat6 and presumably Cat7 and Cat8 in order to reach specified bandwidth:

 

"The twist rate (also called pitch of the twist, usually defined in twists per metre) makes up part of the specification for a given type of cable. The greater the number of twists, the greater the attenuation of crosstalk. Where pairs are not twisted, as in most residential interior telephone wiring, one member of the pair may be closer to the source than the other, and thus exposed to slightly different induced EMF.

Where twist rates are equal, the same conductors of different pairs may repeatedly lie next to each other, partially undoing the benefits of differential mode. For this reason it is commonly specified that, at least for cables containing small numbers of pairs, the twist rates must differ."

 

Evidently the twist rate is unique from manufacturer to manufacturer and since Cat7 is so new, who knows what some of these companies are doing.

 

I came across a pretty interesting discussion here:

 

"There is no spec, on what pairs have a specific twist rate. A minimum twist rate is implied by the noise immunity required to meet the specification of the entire cable. But the rates on the individual pairs is manufacturer specific, and not dictated by the networking specifications. The networking specifications don't specify how the wire manufacturers perform the desired specs, they only specify what requirements are in place... dB of rejection on adjacent pairs, dB of rejection of adjacent cable, etc.

Note that using a pair with a higher twist rate will give a higher noise immunity, but this does not necessarily result in a better picture when using balun's. This is because the higher twist rate also results in a higher capacitance for that pair. This can be modeled as each strand of the cable being a series string of low valued resistors, and the node between each resistor having a capacitor connected from one conductor to the other. (Looks like a ladder, with the sides being resistors, and the rungs being capacitors.)

This model is a low pass filter! Above the corner frequency of the RC filter formed by the resistance of the conductor, and the capacitance of the twist, the cable looks like a short to high frequencies. So this twist reduces susceptibility to noise, but does so at the expense of bandwidth. These cables carefully balance the resistance, and capacitance in an effort to provide noise immunity while preserving as much bandwidth as possible, while keeping manufacturing cost reasonable. Like many things in life, this is a balance, and the best overall result is achieved by carefully balancing the behaviour, weighting the factors for what is typically seen in real applications."

 

TL;DR - Twist rate increases as you go up, however it is manufacturer specific the exact rate and *which pairs* get what rate. Already I see reviews on Amazon of cables opened where the twist rate was not optimal. So this is a factor that could tie in the variation in results but nevertheless consistent as we go higher and higher (based on what we know so far).

[wushuliu]

Lol, Ebay Supra Cat8 stock almost depleted in less than 24hours.

[wushuliu]

30 minutes ago, Cornan said:

 

Man you’re quick! ⚡️Thanks to you it will be a walk in the park making my Supra Cat 8 DC cables without the usual trials and errors involved! Great work! ?

 

Glad to see you're ready now to try this tweak.

[wushuliu]

Since I guess we are now talking about actual ethernet use.

re: Supra RJ45 connectors on ebay (US)

 

Yes! We are currently out of stock - but a shipment from Sweden is due here any day now, The item will be listed on ebay by the end of the week.

[wushuliu]

10 minutes ago, seeteeyou said:

Dunno what to say but the OP seemed to have abandoned this music server ship

 

http://www.tirnahifi.org/forum/viewtopic.php?f=15&t=4541&start=160

 

http://www.tirnahifi.org/forum/viewtopic.php?f=15&t=4541&start=180

 

Even powering the motherboard with SR7EHD from Paul Hynes plus feeding LT3045 directly to RAM couldn't save the day.

 

Yes, using an SD Card player pays big dividends with sound quality for the cost - especially once modded. Downside is the card readers are usually cheap and a little flimsy, and they have 32gb limitations. On ebay they are called 'Digital turntables' and that's pretty accurate in terms of inconvenience. But if that's not a deal-breaker and you have some basic soldering skills (to replace clocks and improve power supply), they sound really really good.

 

Anyway, that's a bit off-topic isn't it?

 

 

[wushuliu]

On 5/20/2018 at 4:26 PM, lmitche said:

Hey, has anyone tried the Supra Cat 8 as a network cable compared to say a BJC Cat 6a?

 

 

Did you compare the Supra directly to the Gotham? Maybe I missed that post.

[wushuliu]

8 hours ago, paulkouhan said:

Can someone explain to me the purpose of the cable that connects the shielding from both sides ?

 

Thanks!

 

John Swenson Shield Guidelines

 

"PS. For people not aware about the JSSG loop it is is simply a cable shield that is not connected to any of the plugs. Instead there is a drain wire loop that runs along the shield." - H/T Cornan

 

Unfortunately, I can't find Swenson's original post/statement, so I'm not sure what else it involves.

[wushuliu]

14 minutes ago, paulkouhan said:

 

 

Thank you, I have just find it :

https://www.computeraudiophile.com/forums/topic/31554-diy-dc-power-cables/?page=9#comment-659092

 

 

Excellent. Thanks!

 

Re: LT3045, it's worth using two in series for improved performance.

[wushuliu]

6 minutes ago, charlesphoto said:

 

There would be too much voltage drop down between the microRendu and LPS-1. Pretty happy now, I think some more burn in needed. 

 

I meant in general. I have no idea what the specific specs are for either of those. Two LTs in series would only need ~2V drop.

[wushuliu]

5 minutes ago, lmitche said:

Please read my last post above.

 

It just says DC cables being used as DC, network for network, and that you've already converted a bunch of DC to Gotham. So it sounds like you're just using the Supra for ethernet?

 

 

[wushuliu]

Ok, well I was hoping at some point there would be attempts made to really compare and hashout cable choices and construction to get to the heart of this, but it's become more like a Choose Your Own Adventure and already stalling out. Too bad. This line of inquiry had real promise. Hopefully Swenson/Superdad will pursue this.

[wushuliu]

7 hours ago, charlesphoto said:

 

You do realize that we’re just having fun bodging together bits of cable to see if we can make our hifi’s sound better, and not trying to perfect a self driving car or some such mission critical project? Plus the parts are cheap, and it’s only low voltage so not much danger involved. Computer audio is a fast moving target. You can wait, or you can do. I’m glad I didn’t wait and am enjoying the best sound from my system yet. 

 

That's a hell of a strawman. I was 'doing' this tweak before it showed up here. Glad you got great results. Maybe you could have had better results. We won't know. Enjoy.

[wushuliu]

19 hours ago, JohnSwenson said:

I just got some bulk Supra CAT8 to try this out, how are people wiring this for DC cable? There are 4 twisted pair, each individually shielded. Is it just two pairs "-" and two pairs "+" or something interesting like all solids + and all stripes - ?

 

Boy is this stuff stiff though. The shielding around each pair is VASTLY thicker than the usual foil shield you see, which is usually  a few atoms thick of aluminum deposited on mylar. This actually looks like heavy aluminum foil bonded to the mylar.  The foil part is on the outside, so the foil from all the pairs touch each other. There is a sparse weave of wire around this bundle, which as far as I can tell is not an extra shield, it is just a "drain wire", an easy way to solder to the shields and tie all the shields together.

 

Anybody know what the material is around the wires? I could not find that out. It seems very soft, it might be a foamed material.

 

I have the setup to run an impedance VS frequency test, I can compare this and a Canare cable.

 

It might be a couple days before I can work on this.

 

John S.

 

Hi John, if possible can you also add an IBRA Cat7 ethernet cable as well as (based on lmitche's experience), the Gotham Audio cable he used? I'm sure some of us would be willing to send you samples if needed, since excellent results have been reported from all three.

 

[wushuliu]

18 hours ago, lmitche said:

We have no room for your attitude here. The ends don't justify the means. We mean to have fun and enjoy each other's company. If you don't like it, please go back to where you came from.

 

Will do.

[wushuliu]

18 hours ago, lmitche said:

We have no room for your attitude here. The ends don't justify the means. We mean to have fun and enjoy each other's company. If you don't like it, please go back to where you came from.

 

'go back where you came from'? Really? I've been a member since 2010.

 

And just for the record. None of my posts have been personal attacks.