SMPS and grounding

[Superdad]

14 minutes ago, tboooe said:

So now I am a bit confused.   I thought it didnt make sense to ground the output of an LPS because given how they work there is no high freq noise to deal with with.

 

a) It's not high frequency noise, it is is high-impedance common-mode leakage (which has both high and low freq. components);

 

b) You are correct that grounding the output of a linear supply is not needed--except with regards to the specific Netgear switches that John tested, for which grounding whatever power supply is used allows that Ethernet switch to shunt leakage currents coming in on the CAT cable from other upstream gear.  So it is not so much that you are grounding the PS for this switch, just that it is the easiest place to ground those unique switches (and which if you are using an SMPS for it--just fine--will also take care of ITS high-impedance leakage).

[Superdad]

17 minutes ago, H-Man said:

Looking at this it became an easy decision to clean up the SMPS around my main music system.  Looking at the possibility of adding a JS-2 I am wondering what to power with what? In the system today is Sonore Ultra Rendu powered with LPS-1, now with shunted SMPS, Netgear GS108 with shunted SMPS, Brooklyn DAC using internal SMPS, MBL amps and an Audessey SUB controller powered powered with external SMPS. 

 

Hi Henrik:

 

Your Brooklyn DAC is screaming for the JS-2!  Without a doubt that would be the best first use for our acclaimed choke-filtered, dual-output, 5-7 amp linear power supply.

I need to send Mytek a holiday gift this year as I have lost count of how many Brooklyn DAC owners have employed the JS-2 to elevate that fine DAC.

Here is a typical e-mail--from a client a few months back:

Alex,
Thank you for the JS-2.  I connected it to Mytek Brooklyn and the Microrendu.  The sonic results exceeded my expectations by a wide margin.  The sound with the JS-2 became much more clear, more defined and simply more natural.  Never thought that DC power from one unit or another  can be so far apart in quality when feeding good quality audio equipment where the results are clearly audible.
Thanks a lot,
John
 

I really don't like selling the JS-2 for little stuff (the design is too good and we put too much time into each one to have it wasted).  It really shines with DACs and other actual audio components.  I think we have built and sold over 500 JS-2s by now and nobody is ever less than thrilled.

 

Time to pack for Turkey Day!  Best holiday wishes to those who are here in the States.

--Alex C.

[Superdad]

Just now, beerandmusic said:

wow 29 pages....

if i am not a DIY kinda guy, is there one relatively inexpensive ps i can buy to power all necessary devices which would resolve any/all of the issues discussed in this thread?

 

Well what would you like to power?  And what connections--of Ethernet, computer, switches, DAC, etc.--are part of the system?

[Superdad]

29 minutes ago, beerandmusic said:

 

Perhaps i wasn't clear....If the DIY shunt will suffice, and is really really easy, i may go that route.  I did read in the thread that this shunt is not needed if you get the LPS-1, hence why i said I may go the route of an "off the shelf solution" vs a diy, but i would prefer if there was some single ps that could be used for all my devices...but this is where my inexperience is...maybe they don't make such a PS that could be used as both an isolation ps, power conditioner, and LPS outputs for devices that could use one (grin).  For the short term, a DIY shunt for the nativ vita may make sense in regards to this thread.

 

Most of the components you listed have their own INTERNAL AC>DC power supplies--be they linear, switch-mode, or hybrid.  Such products lend themselves to neither the use of an external DC power supply nor the use (or possibly the need of) for shunting of AC mains ground to DC zero-volt output ("ground") to eliminate high-impedance AC mains leakage as discussed in this thread.

[Superdad]

21 minutes ago, beerandmusic said:

i am pretty sure the nativ pulse is an optional item, not included, but i will check.

 

Yes, it is $999 additional.  Standard supply that comes with the Nativ Vita is small SMPS brick--with their own USB-C-looking plug on the DC cable.

 

We are now way off topic! 

[Superdad]

2 hours ago, charlesphoto said:

I have a JSGT on my HDPLEX 100 powering my LPS-1 with the 12v rail and i think it makes a difference. 

 

FYI to all:

Of the 1,600+ UltraCap LPS-1 units sold, we have had 10 field failures--virtually all due to overvoltage input spike frying a particular regulator chip. 

7 of those 10 were from people charging their LPS-1 with an HDPlex power supply.

We can not cover under warranty failures caused by third-party "energizing"/charging supplies.

 

HAPPY NEW YEARS to everyone!   And thanks for making 2017 a terrific year for UpTone Audio.

--Alex C.

[Superdad]

10 minutes ago, octaviars said:

 

Do you know exactly what HD Plex it was? There are more than one model.

 

The 100W and 200W (though from photos of their interiors it is hard to believe that the newer model really has twice the output capability of the older unit).

[Superdad]

34 minutes ago, octaviars said:

I suppose the electronics in your LPS-1 is rated at a 12vdc maximum but at what voltage does it fry the circuits?

 

12V is the max we approve of for continuous input.  A spike of 18V or more will quickly fry one of our input regulators.

[Superdad]

12 minutes ago, octaviars said:

 

Was this during normal operation that the HD Plex fried the LPS-1 or did something break in them? Did the users use the12Vdc output or the adjustable 5-19,5Vdc output if you have that information?

 

It varies. Sometimes the fixed outputs, sometimes the variable, and often failure of the HDPlex in the process.  And the LPS-1 is not always the only item damaged.

Since virtually all the support we provide is via e-mail (though I enjoy phone calls as a break  and such are often more productive than e-mail), I have documentation of all this--plus the returned boards with burnt parts.

 

It is not my intention to be negative about the value-oriented HDPlex units--and I understand that Larry Liu provides excellent support to his customers.

I just felt the need to point out that we can not warrant the LPS-1 against damage by excessive voltage from 3rd-party supplies--and for whatever reason an HDPlex was involved in 7 of the 10 failures we have seen.

 

If you have further questions about this matter, please write to me.

[Superdad]

1 hour ago, agladstone said:

I guess I better start putting a JS-2 fund together fast for my DAC!  

 

Your would never regret that. 

About 50 Brooklyn DAC owners bought JS-2s in 2017 (I ought to write to Mytek to ask to be listed with the other LPS units on the Brooklyn page).

There are qualities to the design and execution of our choke-filtered, dual-output unit that go beyond just its 5-7-amp rating and make it an exceptional performer with a real audio component such as a DAC.

And the JS-2 is easily the most reliable, trouble-free product I have ever produced.  We have more than 600 of them out there with only two field failures ever.

In December we managed to build ahead a bit, so as of today there are 8 units ready to go at any time (though they won't last on the shelf).

 

Cheers!  

--Alex C.

[Superdad]

Gentlemen:

While I know it was me who mentioned concern--about using HDPLEX units to charge LPS-1s--I now ask that discussion of HDPLEX power supplies be taken to a thread not located in the UpTone Audio sponsored forum area.  

I simply do not feel it is polite to the good folks at HDPLEX for such discussion to take place in our forum.

Thanks,

--Alex C.

[Superdad]

19 hours ago, JohnSwenson said:

So the answer depends on the DAC. If it implements techniques that block high impedance leakage then they will be much more susceptible to high impedance leakage. If the DAC does NOT block low impedance leakage then it will be sensitive to both types.

 

 

Thanks for your post John.  Above is the only sentence that did not make sense to me.  Perhaps there was a typo error or that your phrasing is confusing.

----------

 

To clarify for others regarding what John said about the limits of his test gear:  His setup can go plenty low--to easily show the differences at any meaningful levels.

 

Here are 3 graphs--directly measuring leakage versus frequency.  (do not try to compare these to anyone else's measurements--scales and units are different; and these are in dBM not dBV, that's 13dB difference right there).

 

Here is the leakage (just up to 1KHz, John has done wider bandwidth measures as well) from a stock Mean Well GST40A:

 

Here is the same Mean Well unit with its DC zero-volt ("ground") tied to the ground pin of its IEC320-C14 inlet this way:

 

 

What you see remaining is all the low-impedance leakage. (Again this is the leakage measurement of just the grounded GST40A.)

 

And here is the leakage (not output noise; these are all common-mode leakage tests) from an LPS-1 being powered by the same modified Mean Well:

You can see how all the low impedance leakage is now blocked.

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

 

As John mentioned, some tests have been performed, including on the new SMPS we chose (and he built separate test boards with the paralleled LT3045s months ago), so it is not as if we don't know what to expect.  We just intend to wait until the final production boards are here before publishing more graphs.  

I know patience is not a plentiful virtue around here.  But trust me, we will get there.  All good things in due time...

 

--Alex C.

[Superdad]

10 minutes ago, Em2016 said:

Much appreciated for sharing your measurements. For 'completeness' are you kindly able to include the leakage current measurements image for the JS-2 also?

 

It is also down in the weeds:

[Superdad]

2 minutes ago, barrows said:

Remember not to simplify things folks, leakage current is not the only thing which matters, differential noise is still important, it is not just about leakage current.

 

No kidding!  Yet even over at our LPS-1.2 thread--where we announced paralleled LT3045s for ultra-ultra-low-noise output and 3mOhm wideband output impedance, these guys still want to get hung up on the fully solved leakage issue. 

[Superdad]

13 minutes ago, Em2016 said:

Absolutely. Some of us aren't getting 'hung up' on this. Some of us just find it interesting and this thread is essentially only about leakage current. I find it interesting anyway.

 

I know.  I was just kidding.  

[Superdad]

1 hour ago, R1200CL said:

Alex

My Meanwell is NOT the same as yours. 

I need your or @JohnSwenson confirmation that I can perform the JSGT on this type of Meanwell SMPS.

 

Yes, you have it correct.  Solder wire from IEC320-C14 AC ground pin to the terminal on the bottom of the board corresponding to where the zero-volt DC “ground” output wire is attached.

Be sure not to form a short with any other PCB pad.  Be sure to reinstall the metal clip that you removed off of the thermal rubber boot covering the TO220 regulator.

 

[Disclaimer:  Neither myself, John Swenson, nor UpTone Audio are recommending the opening of AC mains connected power device to perform this or any other modification.  We are not liable for any injury, hazard, or equipment damage resulting from such tampering.]

[Superdad]

2 hours ago, wakka992 said:

I'm about to receive my LPS-1 and I was looking for a SMPS already internally shunted instead of going with the external adapter route as per your quoted message.

 

I am assuming that you are getting a second-hand LPS-1 since the last production of them was sold out by us months ago and the enhanced UltraCap LPS-1.2 begins shipping on the 15th.  It comes with a "energizer"/charger that is already internally "ground-shunted."

 

2 hours ago, wakka992 said:

I think I've found a Meanwell unit that should do the trick, but I can't figure it out if what I'm reading from the datasheet is correct or not.

 

The Meanwell I'm speaking about are the AC-DC medical power supply from GSM40A and GSM60A series.

From the figures I think they are grounded/earthed at the "outside" of the Standard DC plug P1J.

 

Having checked a bunch of Mean Well units, including a couple of the their "medical" ones, I can tell you that the odds of the one you are looking at being designed with its DC zero-volt output "ground" common to the AC inlet ground are very slim.  For whatever reason, Mean Well does not seem to do this with any of their units.  I tried for months to get an answer from the factory about this--and to get them to make us 1,000 units with the change--and got nowhere.  That's why we moved to a different supplier for the LPS-1.2 charger.  Even then, the shunting is not something that is found in the spec sheets--we had to buy lots of samples to find one.

 

After the first 250 LPS-1.2 orders are shipped, we will begin offering our 7.5V/4.8A/36W adapter separately for $15 to those who want one.  Until then, there is a CUI brand 12V/2.5A/30W unit available in the US from DigiKey and other distributors (https://www.digikey.com/products/en?keywords=102-4104-ND.  This is one that I personally confirmed connects AC ground to DC output "ground." 

 

Hope this helps.

--Alex C.

 

[Superdad]

11 hours ago, wakka992 said:

BTW I think I think I discovered what Meanwell means with that "-V connected to AC FG" on the datasheet --> it shoul be "external of the DC barrel conected to the AC Frame Ground".  Does that mean the Meanwell GSM40A and GSM60A I posted about earlier are shunted?

 

Good catch.  It might mean that.  You would have to buy one and check it with a meter.

[Superdad]

38 minutes ago, sockpit said:

This may have been asked above.  I skimmed through the many pages and did not see it, though.

 

If one wanted to avoid using a separate outlet for the shunt, could one simply run the ground wire back to the ground pin of the stock Meanwell that comes with the LPS-1 (and is not in fact being used by that SMPS)?  

 

I have in mind soldering it to the pin at its very base, or using a connector (attached) that slides tightly over the ground pin.

 

Yes, that would work fine! 

[Superdad]

37 minutes ago, sockpit said:

Ok, so assuming you can get a good connection, could one do the same with the DC barrel of the meanwell and dispense with the male-female screw terminal extras?  It’s the outer barrel of the Meanwell dc output I want to ground, right?

 

strikes me as cheaper and more elegant solution . . . 

 

Yes, that will work as well.

[Superdad]

30 minutes ago, Em2016 said:

Hi Alex, will this be offered soon-ish?

Or will you need a vacation first, after the success of the first 250 shipped LPS-1.2's ?

 

Have put it on my calendar to try to get to within the next 10 days.  Need to finish this week's shipments of LPS-1.2s--the very last of the first 250--and to make sure that all parts are tracked down for the next batch for March.  Priorities!  

[Superdad]

9 minutes ago, Em2016 said:

Thanks Alex. I saw a photo of the PSU and I think I saw the 'C-tick' safety approval for use in Australia.

Is that the same PSU that your shipping at the moment (and will ship separately later)?

 

Yes,  this one:

[Superdad]

9 hours ago, jrd1975 said:

Will you be selling a UK version???

 

The new internally-shunted, 7.5V/4.8A/36W charger which ships with every UltraCap LPS-1.2 unit is world-voltage compatible (from 100V all the way to 240V, 50/60Hz).

It takes a standard detachable IEC320-C14 AC mains cord. When we ship this charger will the LPS-1.2 we include a 45cm long AC cord with a USA plug.  For a variety of reasons (logistics, availability, and weight/bulk of longer cords--the only kind available with overseas plugs) we do not include or offer AC cords with UK, Schuko, or Australian plugs.  The cord to the charger does not matter, and most everyone has a spare "computer/audio" AC mains cord with a local plug laying about.

 

I apologize for not yet having the UpTone-branded SMPS up for sale on our site.  Part of it has to do with setting up reasonable shipping charges for overseas.  We will sell these for $15 (just enough to cover our costs, handling, PayPal/CC fee, and the pouch to ship in), but First Class Mail (in a padded pouch) of the 11 ounce package is $22 to all overseas destinations.  And Priority Mail (in a USPS Flat Rate mailer is $34).  I know it seems crazy, but even with my commercial rate pricing for our volume business, this is what we pay to ship.

(I am always amazed when I can get small items shipped from China, via what they call E-packet, for next to nothing.  But then I have read that the Chinese government subsidizes their postal system in a big way.)

 

Anyway, I am sure I'll put this unit up on the site soon.  One nice thing is that it does not cost anything extra to ship if bought at the same time as one of our other main products.  We can easily squeeze it into the Flat Rate package of an UltraCap LPS.1.2 or ISO REGEN. So that is the best way to get one without paying any silly postage just for it.

 

 

[Superdad]

4 minutes ago, Confused said:

Great news re the charger.

One question.  For those of us in the UK (or Europe), are there any plans to sell the new charger via VortexBox?  Or will this one be direct from the US only?

 

Good idea! I just made a note to myself to ask Martin (VortexBoxUK/Audiostore) if he would like us to include a half-dozen extra chargers in with his next dozen shipment of UltraCap LPS-1.2 kits at the end of the month.

[Superdad]

2 hours ago, Confused said:

Did he say yes?

 

Have not asked him yet.  Will this week.