DIY DC power cables

[Forehaven]

18 hours ago, sandyk said:

Hi Greg

 I have deliberately avoided using SM resistors where possible due to the need to easily measure the values of the resistors often sold on quantity strips,(fiddly) as well as difficulty sometimes reading the marked values.

  I have also had poor past experiences with their resistance tolerance %. 

One version of the PSU PCB (no trimpot version) that I use extensively in my DACs and Preamp etc. that was designed by DIY Audio member Greg Erskine also has provision for a couple of SM resistors in the voltage setting area, where these Susumu resistors would have been ideal ( trimming purposes) It can  also use either through hole or SM diodes such as the ES1D, (which I have used) in the bridge rectifier section.

 

Kind Regards

Alex  

 

Alex,

 

I accidently attached a 7V LT to power source to wrong end and blew this component (the beige square chip).  Can you tell me what this is exactly so I can order one and see if I can do a SMD solder joint and repair this board?

cid:6BDEDA20-2D73-4045-A847-148A390F47F7

 

Thanks Alex!

[tapatrick]

On 1/1/2018 at 1:14 AM, sandyk said:

In other words, you could make a simple PSU using a transformer, perhaps using a Bridge rectifier (or 4x Schottky diodes) followed by a large value filter capacitor, then connect it directly into the input of a LT3045 PCB.

In fact, if you used a high quality R Core transformer , you could do this to make a very high quality, low noise, stand alone PSU using a metal case to house it all !

 

IIRC, Greg has already covered this aspect recently.

I did consider this project but decided its outside my skill set (and available time..). My modded Teradak feeding the LT3045s chains is
more or less the same result. Thanks for your continued input and advice @sandyk

[elan120]

30 minutes ago, Forehaven said:

Alex,

 

I accidently attached a 7V LT to power source to wrong end and blew this component (the beige square chip).  Can you tell me what this is exactly so I can order one and see if I can do a SMD solder joint and repair this board?

cid:6BDEDA20-2D73-4045-A847-148A390F47F7

 

Thanks Alex!

Sorry, I am not Alex...but if you are referring to the larger "beige square chip" next to the RED/WHITE cable, it is the 47uF/25V/10% Tantalum capacitor with 2917 case size made by Kemet (T495D476K025ATE250).  The other 4 "beige square chip" are 10uF/25V/10% X7R, 1206 case size capacitors made by Murata (GRM31CR71E106KA12L).

 

Hope this helps.

[tapatrick]

23 hours ago, Cornan said:

My order of this 3A LT3045 board was just confirmed by Stammheim at DiyAudio. I am looking forward to give this beauty a try pre my Brooklyn DAC! ?

 

Nice!

[tapatrick]

4 minutes ago, elan120 said:

Sorry, I am not Alex...but if you are referring to the larger "beige square chip" next to the RED/WHITE cable, it is the 47uF/25V/10% Tantalum capacitor with 2917 case size made by Kemet (T495D476K025ATE250).  The other 4 "beige square chip" are 10uF/25V/10% X7R, 1206 case size capacitors made by Murata (GRM31CR71E106KA12L).

 

Hope this helps.

Yes, looks like the Tantalum input cap. I've blown one of them and also replaced them with other caps. It is fairly easy to replace if you are an average solder-er..

[Forehaven]

26 minutes ago, tapatrick said:

Yes, looks like the Tantalum input cap. I've blown one of them and also replaced them with other caps. It is fairly easy to replace if you are an average solder-er..

Awesome guys! Thanks!  i've nothing to loose by trying 

[sandyk]

3 hours ago, Forehaven said:

Alex,

 

I accidently attached a 7V LT to power source to wrong end and blew this component (the beige square chip).  Can you tell me what this is exactly so I can order one and see if I can do a SMD solder joint and repair this board?

cid:6BDEDA20-2D73-4045-A847-148A390F47F7

 

Thanks Alex!

 

 It's hard to tell from the photo, and a search for what you quoted gave no results.

It appears to be a Surface Mount Electrolytic capacitor. However, it is highly likely that there is other damage, including the I.C.s due to the incorrect voltage  polarity.

This is a very different situation to when you are constructing something and inadvertently insert an electrolytic capacitor around the wrong way and blow the crap out of it. (Been there, done that )

[sandyk]

2 hours ago, tapatrick said:

I did consider this project but decided its outside my skill set (and available time..). My modded Teradak feeding the LT3045s chains is
more or less the same result. Thanks for your continued input and advice @sandyk

 

 Yes, it can be quite time consuming, especially making the correct size holes in metal for AC mains sockets etc.

[tapatrick]

13 hours ago, sandyk said:

 

 Yes, it can be quite time consuming, especially making the correct size holes in metal for AC mains sockets etc.

for sure  I wouldn't win any awards for the looks of my diy stuff.. and often when you add up the parts cost and time, a ready made piece can be a no brainer 

[Forehaven]

19 hours ago, sandyk said:

 

 It's hard to tell from the photo, and a search for what you quoted gave no results.

It appears to be a Surface Mount Electrolytic capacitor. However, it is highly likely that there is other damage, including the I.C.s due to the incorrect voltage  polarity.

This is a very different situation to when you are constructing something and inadvertently insert an electrolytic capacitor around the wrong way and blow the crap out of it. (Been there, done that )

Any way to check for other damage Alex?  Otherwise I guess I'll just toss it.

[gstew]

 

20 hours ago, sandyk said:

 

 It's hard to tell from the photo, and a search for what you quoted gave no results.

It appears to be a Surface Mount Electrolytic capacitor. However, it is highly likely that there is other damage, including the I.C.s due to the incorrect voltage  polarity.

This is a very different situation to when you are constructing something and inadvertently insert an electrolytic capacitor around the wrong way and blow the crap out of it. (Been there, done that )

 

I was going to make a comment similar to Alex's (though less eloquently). 

 

1 hour ago, Forehaven said:

Any way to check for other damage Alex?  Otherwise I guess I'll just toss it.

 

Forehaven, if you are in the US, I'd be happy to check it out for you & repair/rebuild for a small fee. PM if interested. I just  built up 2 more of the 2x 3||LT3045 boards yesterday with 100% success (and have done a fair number of other SMD-board builds and mods successfully), so I  am comfortable doing this. 

 

6 hours ago, tapatrick said:

for sure  I wouldn't win any awards for the looks of my diy stuff.. and often when you add up the parts cost and time, a ready made piece can be a no brainer 

 

20 hours ago, sandyk said:

 

 Yes, it can be quite time consuming, especially making the correct size holes in metal for AC mains sockets etc.

 

I DIY much of my gear so I can do things I have found to be 'better' or that can't/won't be done commercially. For example, I use a good 'audiophile' solder.. which happens to be leaded, where almost all commercial products are now ROHS compliant. I structure the gear to minimize wire lengths, number of connections, and non-soldered connections. I'll use what I consider 'better' parts/components where appropriate. I build-in or add vibration damping & control. I use wildly overbuilt power supplies. While many of these only make small differences by themselves, in my experience, you put them all together and they can can make significant differences.

 

Of course, I have to observe my limitations. That's when I buy a piece of gear. For example, I use PS Audio P10 AC Regenerators and BHK-250 amps. I could not effectively duplicate either of these... I don' t have the audio design and engineering experience and training  nor do I have the appropriate test gear.

 

But from cables to power supplies up to phono stages & DACs (where I can work with other's designs or pre-made modules such as those from Soekris or Twisted Pear Audio), I can do some pretty good components, at least to my ears. This is worthwhile to me, as I can't buy gear that addresses all of these (and other) areas OR can't afford the gear that does.

 

And ALL of my DIY'd gear is MASSIVELY ugly. IMHO, doing it 'right' rarely means doing it 'pretty'. 

 

Greg in Mississippi

[tapatrick]

9 minutes ago, gstew said:

I DIY much of my gear so I can do things I have found to be 'better' or that can't/won't be done commercially. ...

 

And ALL of my DIY'd gear is MASSIVELY ugly. IMHO, doing it 'right' rarely means doing it 'pretty'. 

 

Greg in Mississippi

Greg, I see your posts on lots of forums that I look at to try and learn stuff and you are definitely the king of DIY.

cheers and thanks for your input .;)

[[email protected]]

23 hours ago, sandyk said:

 

 It's hard to tell from the photo, and a search for what you quoted gave no results.

It appears to be a Surface Mount Electrolytic capacitor. However, it is highly likely that there is other damage, including the I.C.s due to the incorrect voltage  polarity.

This is a very different situation to when you are constructing something and inadvertently insert an electrolytic capacitor around the wrong way and blow the crap out of it. (Been there, done that )

Usually only tantalum capacitor affected, you can just remove burned capacitor, clean pcb with pure alcohol (can use vodka but not whisky), it should work without tant. capacitor.

you can get replacement from digikey

https://www.digikey.com/product-detail/en/T495D476K025ATE250/399-10299-1-ND/3760380?utm_campaign=buynow&WT.z_cid=ref_octopart_dkc_buynow&utm_medium=aggregator&curr=usd&site=us&utm_source=octopart

[sandyk]

3 hours ago, gstew said:

 

 

23 hours ago, sandyk said:

 

 It's hard to tell from the photo, and a search for what you quoted gave no results.

It appears to be a Surface Mount Electrolytic capacitor. However, it is highly likely that there is other damage, including the I.C.s due to the incorrect voltage  polarity.

This is a very different situation to when you are constructing something and inadvertently insert an electrolytic capacitor around the wrong way and blow the crap out of it. (Been there, done that )

 

I was going to make a comment similar to Alex's (though less eloquently). 

 

4 hours ago, Forehaven said:

Any way to check for other damage Alex?  Otherwise I guess I'll just toss it.

 

Forehaven, if you are in the US, I'd be happy to check it out for you & repair/rebuild for a small fee. PM if interested. I just  built up 2 more of the 2x 3||LT3045 boards yesterday with 100% success (and have done a fair number of other SMD-board builds and mods successfully), so I  am comfortable doing this. 

 

10 hours ago, tapatrick said:

for sure  I wouldn't win any awards for the looks of my diy stuff.. and often when you add up the parts cost and time, a ready made piece can be a no brainer 

 

23 hours ago, sandyk said:

 

 Yes, it can be quite time consuming, especially making the correct size holes in metal for AC mains sockets etc.

 

I DIY much of my gear so I can do things I have found to be 'better' or that can't/won't be done commercially. For example, I use a good 'audiophile' solder.. which happens to be leaded, where almost all commercial products are now ROHS compliant. I structure the gear to minimize wire lengths, number of connections, and non-soldered connections. I'll use what I consider 'better' parts/components where appropriate. I build-in or add vibration damping & control. I use wildly overbuilt power supplies. While many of these only make small differences by themselves, in my experience, you put them all together and they can can make significant differences.

 

Of course, I have to observe my limitations. That's when I buy a piece of gear. For example, I use PS Audio P10 AC Regenerators and BHK-250 amps. I could not effectively duplicate either of these... I don' t have the audio design and engineering experience and training  nor do I have the appropriate test gear.

 

But from cables to power supplies up to phono stages & DACs (where I can work with other's designs or pre-made modules such as those from Soekris or Twisted Pear Audio), I can do some pretty good components, at least to my ears. This is worthwhile to me, as I can't buy gear that addresses all of these (and other) areas OR can't afford the gear that does.

 

 Likewise.

 It helps though if there is a nice kit available that has predrilled and screen printed cases, and enough room inside to fit little extras, perhaps even an additional transformer and Voltage regulator PCB as well as additional "shunt" regulators etc. . 

 The attached link shows such an item.

http://www.altronics.com.au/p/k5332-stereo-digital-to-analog-converter-kit/

[jean-michel6]

On 20/4/2017 at 9:09 PM, JohnSwenson said:

There has been a lot of posts recently in other threads about making your own DC cables for LPS-1, JS-2, Y adapters etc.

 

I'm going to attempt to give some theory behind DC cables and CA and some hints for making your own, and some results of my own experience.

 

So what is the big deal, DC is, well, DC! Resistance should be the only thing that matters, right? Wrong! Particularly for power digital circuits some AC issues actually do make a big difference. This is due to the fact that the load current of most digital devices is not constant, it varies all over the place, and can do so very quickly. This rapidly changing load current causes a voltage to develop across the inductance in the cable. No matter how good the regulator in the power supply is this noise will still be there. This means that both resistance and inductance of the cable matter. Cable capacitance is a good thing, but the ranges available in cables have a very small effect so so you can pretty much ignore the cable capacitance.

 

Are there "cable parameters" that DON'T matter for a DC cable? Yes, anything that primarily affects distortion is not an issue, such as stranding vs solid core, conductor material and plating. The difference in resistance between silver and copper does produce lower resistance than copper, but just making the copper conductor slightly thicker does the same thing. Thus I do not consider the vastly higher price of silver worth it. The net result is that stranding doesn't matter, OCC etc doesn't matter, dialectric has extremely small effect.

 

So what DOES really matter? The wire gauge determines the resistance and the geometry of the wires (how they are arranged in the cable) makes a HUGE difference in the inductance. So things to optimize for, thick wires and use the proper geometry. The geometry is actually far more important than the wire gauge, although you don't want to go with really thin wires either.

 

There are 4 common geometries in use in DC cables:

parallel conductors (zip cord)

coax

twisted pair

starquad

 

They are listed in decreasing inductance, zip cord has about 10 times the inductance as starquad for equivalent gauge. Coax and twisted pair are pretty much the same at about 1/3 the inductance of zip cord.

 

All can be shielded or not shielded. The shield does not really make things better for most applications of DC cables, but if it is done wrong (which is extremely prevalent) it can make things worse. Thus I recommend using unshielded cable for most situations.

 

I hope from the above you come to the conclusion that using starquad is a good thing when making your own DIY DC cable.

 

So what is starquad? It consists of four conductors, the whole group of which is twisted in the cable. This is NOT two twisted pairs. They are not woven or braided, the four conductors are arranged in a square. Diagonally opposite conductors are connected together at both ends of the cable. That is it, not very complicated. There are many articles on the net covering starquad with nice pictures. (sometimes it is called star quad, sometimes star-quad, they are all the same thing)

 

So what is special about starquad? Well of course you have two wires in parallel which halves the resistance, but the big thing is the magnetic field, it forms in such a way that the inductance is about 3 times lower than coax or twisted pair, AND it produces an inherent very good shielding effect, without using a shield!

 

So to make your own starquad cable you need a cable with 4 conductors, with the whole thing twisted, preferably unshielded. There are many of these on the market. They do not have to be specifically marketed as starquad. Many cables that say "starquad" have wires with only two colors, diagonally opposite wires have the same color, that makes it easier to figure out which ones to connect together. But cables with different colors for all for wires also work well, you just have to figure out which ones are diagonally opposite each other.

 

So what gauge to use? A 24 gauge starquad microphone cable is probably too small, and a 14 gauge speaker cable is probably going to have wires that are impossible to connect to the barrel connectors most components use. So somewhere in between is probably a good choice, 20 or 18 AWG wires are probably the sweet spot. Belden 8489 and West Penn 244 are 18AWG 4 conductor unshielded cables that work very well. Canare makes a starquad speaker cable called 4S6 which has 20AWG wires which should be a very good choice as well. 

 

Alex likes to use a cable with a shield which I think just makes things more complicated than they need to be.

 

If you want to make your cable without soldering anything there are barrel plugs with screw terminals available at many places. These terminals will accept a single 18AWG wire nicely, but it gets very tricky to put two 18AWG wires into each connector (which is what you have to do for starquad). The 20AWG 4S6 might be a better choice when using these. If you want to make a Y cable where you put TWO cables into one plug, you may just barely be able to get 4 20AWG wires into each connector.

 

Last night was the first time I was actually able to try some of this myself. Since I am on the road now without my soldering equipment I decided to try a starquad cable with the screw terminals. My entire setup right now is an LPS-1 powering a SqueezeBox Touch (SBT) with Senheiser phones plug in to the SBT. The current setup used a simple DIY 16 AWG zip cord cable with soldered on barrel plugs. So I found a small amount of 244 on ebay and a bunch of screw terminal connectors on Amazon. They were all here yesterday.

 

Then started the fun, the two 18AWG wires do NOT fit well in those screw terminals. Every time I pushed them in a strand or two would not go in and curl off to the side shorting out to the other terminal. I had to try it about seven times to get all 4 wires properly inserted into the plug. The wires are pretty stiff so I had to really tighten those screws down tight to keep them from pulling out. It only took five tries on the other end of the wire.

 

I finally got it together and plugged it in, WOW this was a big improvement! I thought this system sounded amazing, but with this DC cable it was dramatically improved. And that less than 10 dollars!

 

Next I'm going to try the 20AWG 4S6 cable and see how that sounds.

 

John S.

 

 

John ,

 

Thank's for all the good information that you are sharing with us .

I  have ordered and will be testing the 4S6 canard cable that you recommend for my DC cables .

 

However i have one question which  puzzle me . One of your explanation for the good result for this cable is the fact he has by construction a low inductance . This is a very good point for cable that carry AC current but for DC current  only the Ohm law and the resistance should apply to calculate the impedance of the cable?

Thank to shed some light on my question ?

 

[JohnSwenson]

10 hours ago, jean-michel6 said:

John ,

 

Thank's for all the good information that you are sharing with us .

I  have ordered and will be testing the 4S6 canard cable that you recommend for my DC cables .

 

However i have one question which  puzzle me . One of your explanation for the good result for this cable is the fact he has by construction a low inductance . This is a very good point for cable that carry AC current but for DC current  only the Ohm law and the resistance should apply to calculate the impedance of the cable?

Thank to shed some light on my question ?

 

But it is NOT pure DC. Digital devices in particular have rapidly varying current loads, the rise or fall time of the current change can be quite fast. Those rapid current changes through the inductance of the cable can create significant voltage changes across the cable.

 

For something like a preamp the load current may be very constant, and then the inductance doesn't matter, but for digital devices low inductance can make a big difference.

 

John S.

[jean-michel6]

John ,

Thank for this clear explanation .

[BigGuy]

OK, I have the makings for a starquad DC cable.  Since it looks like the 4 conductors are merely twisted like a candy cane rather than an actual braid, how have people kept the twisted wires from unraveling while adding connectors, ground shielding, etc.  IF solid/stiff, I guess it will hold the twist but finer wire may not.

 

Suggestions...?

[Superdad]

1 hour ago, BigGuy said:

Suggestions...?

 

Shrink tubing.  Either short bands every few years inches or over the whole length.

[BigGuy]

16 minutes ago, Superdad said:

 

Shrink tubing.  Either short bands every few years inches or over the whole length.

Easy enough!  Since it will be covered with shield and TechFlex braid then shrinked at ends, maybe I will try short band of electricians tape.

 

Hopefully not 10lbs in a 5lbs but also going to try to assemble with GND wire internal to barrel connector to eliminate screwdowns.

[wakka992]

On 20/12/2017 at 9:19 PM, Cornan said:

 

Thanks, that probably explains why it does'nt sound different. I however very much like the looks of copper braid. The Ghents really looks fabulous IRL. Almost like it glows from within. 

Have you tried the JSSG on ac mains cord yet? All my other cables (DC, Ethernet & USB) have JSSG. Only ac mains cords missing the party (99% starquad ac mains cables though), so I am really curious how it turns out! ? 

I have the very same impressions with JSSG. A great addition that gets even better the more JSSG you add to the chain.

Guys can you please tell me if the JSSG Cat 6A Ethernet from Genthaudio is shielded twisted pair or unshielded twisted pair (U/UTP)?

If I get it right the shield is "floating" and not connected to the ethernet connector...

[Cornan]

7 minutes ago, wakka992 said:

Guys can you please tell me if the JSSG Cat 6A Ethernet from Genthaudio is shielded twisted pair or unshielded twisted pair (U/UTP)?

If I get it right the shield is "floating" and not connected to the ethernet connector...

 

The Ghent ET02 is using a JSSG which is a floating shield with a drain wire connected to both ends of the shield. Not connected to the plugs. The ethernet cable is a Belden 1303E catsnake Cat6A U/UTP. So YES! ?

 

https://www.ghentaudio.com/part/et02.html

[wakka992]

1 minute ago, Cornan said:

 

The Ghent ET02 is using a JSSG which is a floating shield with a drain wire connected to both ends of the shield. Not connected to the plugs. The ethernet cable is a Belden 1303E catsnake Cat6A U/UTP. So YES! ?

 

https://www.ghentaudio.com/part/et02.html

thank you very much for the fast reply @Cornan!

That is what I wanted to hear 

Right now I'm building my own JSSG AC cable.

Genthaudio JSSG Etherner and USB are coming in the house in the next week!

[agladstone]

Just now, Cornan said:

 

The Ghent ET02 is using a JSSG which is a floating shield with a drain wire connected to both ends of the shield. Nit connected to the plugs. The ethernet cable is a Belden 1303E catsnake Cat6A U/UTP. So YES! ?

 

https://www.ghentaudio.com/part/et02.html

Did you notice an improvement in sound quality when adding this vs a regular Cat 6a cable? (I am currently using Bluejeans Cables Cat 6a). Also, if I order the Ghent ET02, do I only need one/ two from the JSGT shunted Netgear GS105 (I have a Baske Ethernet isolator after Netgear GS105 inbwtween two 1ft long BJC Cat 6a right now, so I would need two short ET02 from Switch). OR, is it best to also get a third  ET02 that goes from my Router to the Netgear GS105 Switch, so the entire Ethernet chain from router to GS105 to baske isolator to Aurender music server is all ET02?? Any thoughts? 

[Cornan]

1 minute ago, wakka992 said:

thank you very much for the fast reply @Cornan!

That is what I wanted to hear 

Right now I'm building my own JSSG AC cable.

Genthaudio JSSG Etherner and USB are coming in the house in the next week!

 

You’re welcome @wakka992! 

Great stuff coming! Be sure to post your impressions when you’ve tried it out. I am very satisfied with my Ghent ET02s and ATL Hi-Fi 8 conductor starquad USB cable with JSSG! ?

I have no JSSG on my ac mains starquad cables yet and are very interested how they turn out?