SMPS and grounding

[auricgoldfinger]

2 hours ago, rickca said:

So to use John's grounding technique, does this mean we now need two outlets for each SMPS (unless grounding multiple SMPS from the same wire)?  I'm impossibly dense about electrical things.

 

I'm also impossibly dense about electrical things, but I think the answer to your question is 'yes.'

[auricgoldfinger]

12 hours ago, R1200CL said:

If you buy the PoE version of that GS105, you don’t even need a PS ?

 

All problems solved ?

 

(no one has said the PoE is a no go YET)

 

And then a MicroRendu or UltraRendu driven by PoE......

 

Alex once said it will be fairly easy to make a 12 V LPS-1. Only reprogram the FPGA ?

 

Could we hope for a 12VDC version to all the people now buying 12 V switches ?

 

You could purchase two LPS-1's and hook their outputs up in series, with one set to 7V and the other to 5V to obtain 12V.

[auricgoldfinger]

1 minute ago, thyname said:

 

Anyone? These should be very simple questions - more like a confirmation. Thanks

 

2. You can have other devices on the same switch, but it is best to keep at least 1 empty port between cables.  John has explained why in his posts.

 

[auricgoldfinger]

13 minutes ago, charlesphoto said:

 

I have not seen this explanation. Why is that? 

 

I would say that for what these switches cost (esp used) in relation to the rest of one’s system, just dedicate if possible one to the hifi only. I have a fairly full GS108 currently, but ordered a like new $10 FS105NA off eBay to isolate the streamer and server. Needed more room anyway. 

 

Personally, I’ve gone and grounded just about everything dc that even remotely comes into contact with the hifi and Ethernet and think it’s made a huge difference - transformative. No idea how much of it actually affects sound quality directly, but I am quite sensitive to EMF and can feel the overall level come down, esp in the TV/stereo corner, server closet, etc. I think even the Roku’s look and sound better. I could just be high too..... but at the cost I figured why not? 

 

I don't want to paraphrase what John has written on the subject.  You can search his posts for the most precise explanation.

[auricgoldfinger]

48 minutes ago, charlesphoto said:

Ok. Not exactly sure what or where to search - this forum has became a bit dense to just put in switch and ports and find an easy search result.

 

Go to his profile page and look at his posts.  You can also Google them.

[auricgoldfinger]

40 minutes ago, BigGuy said:

Just read about this alternative to wall warts...and maybe Gopherts tho' it is not adjustable.

 

https://ifi-audio.com/portfolio-view/accessory-ipower/

Wonder how it stacks up noise-wise?

 

Junky, and you still need to use the JSGT.  No reason to spend $50 on it. 

[auricgoldfinger]

1 minute ago, BigGuy said:

Observation or personal experience?  Junky...construction, noise, SQ, all of the above?

 

1. Bought two units, and one stopped working after a few months.

2. John S has said it is one of the noisiest power supplies he has tested. 

3. When powering a microRendu, the sound quality was horrible compared to a JS-2 linear power supply.

 

I suppose you can mitigate some of the noise with John's grounding technique, but you can use a less expensive SMPS and get the same result.

 

I have a like new unit sitting in a box.  If you really want to buy one, PM me and I'll make you an offer.

[auricgoldfinger]

Just now, Superdad said:

 

No, John never said that!  

He has never tested the output noise of the iFi iPower (properly measuring very low PS output noise--across wide bandwidth is not a trivial procedure) and we do not make broad statements against our competitors.

 

What John did measure and say about the iPower SMPS is that its leakage current profile (both high- and low-impedance as at the time he had not sorted the difference) was one of the wildest he has seen. (I have the graphs to concur but it is not appropriate to post them).

 

It is a fact--with no intention to denigrate the good value of their piece--that the iPower is an SMPS wall-wart (with switching noise and leakage just as all others) that iFi has added several parts to produce a unit with much lower output noise than a typical SMPS, though they only state doing so across the audio bandwidth.

 

I am uncomfortable--though partially culpable I see--with this discussion veering into commentary about our competitors' products.  We respect iFi Audio and they seem to respect us.  I would like to keep it that way.

Thanks,

--Alex C.

 

My apologies to both John and you.  Sometimes I get lost amidst all of the technical information.

 

That being said, points 1 and 3 of my post are irrefutable. 

[auricgoldfinger]

I think what they mean is each rail is grounded separately from the others.

[auricgoldfinger]

2 minutes ago, Superdad said:

 

No, it can not be both ways.  Either all the rails share a common ground, or they are all floated from mains ground.

 

Thanks for the clarification. 

[auricgoldfinger]

I definitely would try powering the LPS-1 with the JS-2.  You may find it sounds better than using the shunted SMPS.

[auricgoldfinger]

4 minutes ago, thyname said:

 

So a linear power supply to power another linear power supply. You guys are nuts! LOL!

 

I wouldn't buy a JS-2 for the purpose of powering an LPS-1, but it is an option for one port depending on what other devices can be powered by it and what ultimately sounds best. 

 

In light of @austinpop's comment above, I might try the Brooklyn and LPS-1 first, but it's always good to explore all possibilities.

 

I have 2 y-cables so I can power 4 devices with my JS-2.

[auricgoldfinger]

2 hours ago, Kilauea50 said:

Can someone post a picture of the iFi groundhog connected to the LPS-1 using a Meanwell PS? I am horribly ignorant when it comes to this type stuff