AC Filtering, Grounding Boxes, Linear PSU and Balanced Power.

[YashN]

On 2/12/2018 at 10:47 AM, jabbr said:

 

I’m not offering!

 

I know! It was also just an example. I also know that if you, jabbr, put your mind to it, you'd be successful at it, so then, I wouldn't mind if you were offering.

 

Quote

... well unless you need help saving $$$ on a so-called grounding box ???

 

I'm pretty well-served here as this is what I did:

- I spent a lot of time dissecting the posts by people who actually bought one of the Entreq boxes, and one of the Tripoint boxes on WBF.

 

- I spent time researching, studying, building, testing, setting up critical listening sessions where 1 (me) or 2 persons could listen and discuss their findings.

 

- I built a really, really rudimentary 'signal grounding' apparatus to just quickly invalidate it... well, it wasn't invalidated at all. I was suprised

 

- I built my own AC Filter box

 

- I built my own Custom USB Connector

 

- I built my own very Low-Noise Linear Regulated PSU for the DAC. Since then, I also built a Dual-Rail one for a Modular Synthesizer, using the same technologies

 

So now, since I used various combinations thereof in my system, I know precisely what the so-called 'signal grounding' box does, at least part of it. There's another part which is intriguing, but which I haven't experienced.

 

If anyone has been paying attention, @JohnSwenson , on another thread has shown a simple method to reduce the noisy effects of an SMPS on your setup... If you compare this method with my rudimentary 'signal grounding' and what the Entreq box does, it amounts to a similar thing.

 

This is why I was asking early in the thread whether just linking the chassis of the gear would solve those problems of noisy currents. Speedskater thought that would be the case. In my setup, I found it wasn't enough.

 

Despite also integrating my AC FIlter box (so Chassis interlink + AC Filter Box), that external 'grounding' (I think 'external reference' here would be a better term) still made a difference in sound.

 

This device wasn't expensive to do at all since my only goal here was to rapidly invalidate it: make the simplest form of it I can think of, connect it, listen, and discard the thing as I thought it wouldn't have any effect. Well, we know what happened there. The device as described a couple of times before in this thread is simply this:

 

- a copper tube that I found for cheap at a hardware store here

- the shield from a cheap satellite cable that I found there as well, and flattened

 

That's barely CAD3, maybe $2 max.

 

The point is that I actually tested the thing a while ago in my setup rather than just contemplate in my mind why for theoretical reasons 'this shouldn't work' as so many have been prone to do.

 

The first time I did this I was already flabbergasted: I had built my own power cable based on a Chris VenHaus design. Didn't expect anything at all: after all it's power, just plug it in, right?

 

 

Quote

I’d say take information, and others opinions for what they are worth. I do see a tendency in Audiophilia for folks to latch on to firmly held beliefs without really questioning the basis for these beliefs. 

 

Ideally rational discourse would help  folks question their entrenched (Entreqed???) beliefs, and learn ... 

 

Reasonable opinions, and experiences, are always a value to me, and in my experience, cross-fertilizing domains is a huge way forward

 

If you were trained in Science and Engineering, you take the information, you test it out or try to invalidate it. If you invalidate it, then there's no need to spend more time on it.

 

On the other hand, if you don't invalidate it, then this becomes an interesting pursuit to do further investigations on.

 

At least that's what I do. I learnt a lot doing that and I never viewed Science as a static corpus of knowledge

[YashN]

On 2/12/2018 at 3:23 PM, Ralf11 said:

Is Computer Audiophilia its own domain, distinct from say digital or analog electronics?

 

It's both, but most of the issues are issues related to the interference one has on another. It really is, overall, an electrical problem. And that's why understanding the System itself is what makes you progress on this path.

 

Additionally, there is 'analogue' hidden in what we call 'digital'. This a big source of the issues.

 

Digital people aren't too concerned with the EMI/RFI for audiophile purposes that their digital circuits make: they mostly design to pass a threshold of acceptance which is far less demanding that what audiophilia field requires.

 

and BTW, I always thought it was "my server, my rules"

 

The real question here is: why didn't you think this was already a given?

 

I think you've been around this forum a while, no? You mean you haven't seen people in their threads asking Chris to purge their threads of some drivel? The OP has this leeway provided and acted upon by Chris himself.

[YashN]

On 3/2/2018 at 3:42 PM, Speedskater said:

How does an Original Poster get to set the rules about whether corrections and engineering facts get posted or not?

 

You make no sense at all, so I have no idea what you're talking about.

 

If you have proper engineering facts, do post them. There are a handful of questions I have asked you which you haven't replied to earlier in this thread.

 

Also, if you are the one who wants to post 'corrections and engineering facts', by all means, do so, as I did appreciate you taking the time listing a lot of interesting resources, namely books.

 

However, you also made a mistake about how the return paths work, for which I had to correct you about. Maybe that's why you're bitter about something?

 

If you're so bent on quoting your book knowledge, make sure you quote it properly.

 

If you're talking about marce supposedly offering corrections or engineering facts, well that's entertainment to me because all he did a few posts back if something like 'I thought USB would work like this' or whatever (it's unimportant - he hasn't done the work, he doesn't know but if you really want to know what he posted, just scroll back).

 

[YashN]

On 3/2/2018 at 6:58 PM, sandyk said:

A correction is one thing, but "engineering facts"   may not always be " facts" despite being sincerely believed by some members.

Many Textbooks get periodically updated too, as more recent research shows the need for updating. 

This applies in all areas.

 

Absolutely, these fields are dynamic, not static, as people perfect heir knowledge and their models of the domains they are investigating.

 

Totally agree with you, Alex.

[marce]

3 hours ago, YashN said:

 

 

If you're talking about marce supposedly offering corrections or engineering facts, well that's entertainment to me because all he did a few posts back if something like 'I thought USB would work like this' or whatever (it's unimportant - he hasn't done the work, he doesn't know but if you really want to know what he posted, just scroll back).

 

I do a range of T-shirts and signed photo's

[Speedskater]

3 hours ago, YashN said:

If you're talking about marce supposedly offering corrections or engineering facts, well that's entertainment to me because all he did a few posts back if something like 'I thought USB would work like this' or whatever (it's unimportant - he hasn't done the work, he doesn't know but if you really want to know what he posted, just scroll back).

When 'marce' posts engineering facts, I would put money on them being correct. He as been posting in engineering treads of audio forums for over a decade. Digital circuitry is his day job and he knows of what he speaks.

[marce]

Cheers for that Speedskater.

I was keeping out of this thread as requested, but my name seems to keep popping up... disquieting in a way.

[Speedskater]

I think that when there are different view points on an engineering topic, they should be discussed in an engineering manner.

It should be about information and not about people.

[Ralf11]

with one exception - if you have an expert n a particular topic, it might be a good idea to give some weight to his opinions on that topic, even in the absence of experimental data

[jabbr]

On 3/31/2018 at 11:09 AM, YashN said:

 

I'm pretty well-served here as this is what I did:

- I spent a lot of time dissecting the posts by people who actually bought one of the Entreq boxes, and one of the Tripoint boxes on WBF.

 

- I spent time researching, studying, building, testing, setting up critical listening sessions where 1 (me) or 2 persons could listen and discuss their findings.

 

- I built a really, really rudimentary 'signal grounding' apparatus to just quickly invalidate it... well, it wasn't invalidated at all. I was suprised

 

Very good start.

What I would like to see are some good measurements.

 

Normally I'd say listening is fine and listen to what you like HOWEVER in the case of grounding boxes which have no rational explanation based in what physics of electromagnetism we understand, if the claim so goes against traditional electronics I ask for real measurements to support a difference. 

 

Our ability to measure electrical phenomena goes way above our ability to listen, not that we always know what we are measuring but for example, if there is less noise on the ground plane then that is measurable. 

 

On 3/31/2018 at 11:09 AM, YashN said:

 

- I built my own AC Filter box

 

- I built my own Custom USB Connector

 

- I built my own very Low-Noise Linear Regulated PSU for the DAC. Since then, I also built a Dual-Rail one for a Modular Synthesizer, using the same technologies

 

So now, since I used various combinations thereof in my system, I know precisely what the so-called 'signal grounding' box does, at least part of it. There's another part which is intriguing, but which I haven't experienced.

 

If anyone has been paying attention, @JohnSwenson , on another thread has shown a simple method to reduce the noisy effects of an SMPS on your setup... If you compare this method with my rudimentary 'signal grounding' and what the Entreq box does, it amounts to a similar thing.

 

This is why I was asking early in the thread whether just linking the chassis of the gear would solve those problems of noisy currents. Speedskater thought that would be the case. In my setup, I found it wasn't enough.

 

Despite also integrating my AC FIlter box (so Chassis interlink + AC Filter Box), that external 'grounding' (I think 'external reference' here would be a better term) still made a difference in sound.

 

This is very nice and applaudable.

 

On 3/31/2018 at 11:09 AM, YashN said:

 

This device wasn't expensive to do at all since my only goal here was to rapidly invalidate it: make the simplest form of it I can think of, connect it, listen, and discard the thing as I thought it wouldn't have any effect. Well, we know what happened there. The device as described a couple of times before in this thread is simply this:

 

- a copper tube that I found for cheap at a hardware store here

- the shield from a cheap satellite cable that I found there as well, and flattened

 

That's barely CAD3, maybe $2 max.

 

The point is that I actually tested the thing a while ago in my setup rather than just contemplate in my mind why for theoretical reasons 'this shouldn't work' as so many have been prone to do.

 

The first time I did this I was already flabbergasted: I had built my own power cable based on a Chris VenHaus design. Didn't expect anything at all: after all it's power, just plug it in, right?

 

 

 

If you were trained in Science and Engineering, you take the information, you test it out or try to invalidate it. If you invalidate it, then there's no need to spend more time on it.

 

If you are trained in science and engineering once your listening test detects a difference, you validate this with measurements. You can't publish a physics paper without either theory and/or measurements.

 

 

On 3/31/2018 at 11:09 AM, YashN said:

 

On the other hand, if you don't invalidate it, then this becomes an interesting pursuit to do further investigations on.

 

At least that's what I do. I learnt a lot doing that and I never viewed Science as a static corpus of knowledge

 

No one does, but extraordinary claims require extraordinary validation. Listening tests do not alone validate nor invalidate physics claims -- perhaps psychology.

[jabbr]

On 3/31/2018 at 11:25 AM, YashN said:

 

If you have proper engineering facts, do post them. There are a handful of questions I have asked you which you haven't replied to earlier in this thread.

 

Also, if you are the one who wants to post 'corrections and engineering facts', by all means, do so, as I did appreciate you taking the time listing a lot of interesting resources, namely books.

 

However, you also made a mistake about how the return paths work, for which I had to correct you about. Maybe that's why you're bitter about something?

 

If you're so bent on quoting your book knowledge, make sure you quote it properly.

 

If you're talking about marce supposedly offering corrections or engineering facts, well that's entertainment to me because all he did a few posts back if something like 'I thought USB would work like this' or whatever (it's unimportant - he hasn't done the work, he doesn't know but if you really want to know what he posted, just scroll back).

 

 

Regarding @marce he does have real world engineering knowledge and to prune his comments reduces the value of this wide ranging thread.

 

Now regarding "grounding", suppose we are to design a sound system for the space shuttle or the space station? Let's say that neither weight nor power consumption are a factor (for the sake of discussion). How is grounding different? Assume normal atmospheric pressures. Would the SQ be different? 

[sandyk]

3 hours ago, Ralf11 said:

with one exception - if you have an expert n a particular topic, it might be a good idea to give some weight to his opinions on that topic, even in the absence of experimental data

Gordon Rankin, for example ?

Gordon, the founder and designer of Wavelength Audio, is responsible for among other things, the first consumer DAC to employ Asynchronous USB.

[sandyk]

3 hours ago, jabbr said:

 

Regarding @marce he does have real world engineering knowledge and to prune his comments reduces the value of this wide ranging thread.

 

Now regarding "grounding", suppose we are to design a sound system for the space shuttle or the space station? Let's say that neither weight nor power consumption are a factor (for the sake of discussion). How is grounding different? Assume normal atmospheric pressures. Would the SQ be different? 

 Grounding is more of a reference point , or return path for a signal, including A.C. power from a Substation etc.

The old Analogue Telephone Exchanges for example, had to have VERY  good grounding, otherwise there was some Hum present in the background of telephone calls. This happened at a couple of major Telephone Exchanges in Sydney , that needed to have their earthing systems repaired and improved. This was especially so for Exchanges like Chatswood which was alongside a railway station, and after a large nearby retail complex was opened,  when the complex opened in the mornings , the simultaneous starting of Air Conditioning, lighting etc. caused the Exchange rectifiers some problems on occasion.

[marce]

http://web.mst.edu/~jfan/slides/Archambeault2.pdf

[jabbr]

21 hours ago, sandyk said:

Grounding is more of a reference point , or return path for a signal, including A.C. power

 

The best visual description ive seen is perhaps here:

11 hours ago, marce said:

http://web.mst.edu/~jfan/slides/Archambeault2.pdf

 

Super nice!

 

So assuming a truly floating power supply with zero leakage current. Why do these “ground” issues keep appearing?

 

1) Misunderstanding: ground is not a sink ... see above

2) Too many gadgets, each with their own wall warts etc and too many cables with too much leakage currents ie ground loops flowing everywhere

 

3) ... ???

 

I think that I see (2) in an attempt to correct (1)? I don’t know ... but simplify simplify simplify with well made low leakage and balanced data lines. 

 

[Ralf11]

I wish he had specified what he meant by high freqs.  GHz, MHz or...

[marce]

Which slide?

Generally its all high frequency once you get to sort of 1MHz just some is very and some is ultra...

[Speedskater]

On 4/1/2018 at 5:32 PM, sandyk said:

Gordon Rankin, for example ?

As an expert? Where would we find is books or engineering papers?

Is he referenced in other text books or refereed papers?

[Speedskater]

While 'marce' would be better at referencing digital experts,  some wire, cable and AC power experts are:

Keith Armstrong
Jim Brown
Neil Muncy (RIP)
Ralph Morrison
Henry Ott
Bill Whitlock

[jabbr]

2 hours ago, Speedskater said:

As an expert? Where would we find is books or engineering papers?

Is he referenced in other text books or refereed papers?

There are different types of experts. Gordon Rankin has “done stuff” and made widely adopted contributions. That counts too.

[Speedskater]

I think of an expert as a person that's work is used as a reference in AES or IEEE papers or text books.

That's not to say that there aren't others with vary valuable information.

[marce]

4 hours ago, Speedskater said:

While 'marce' would be better at referencing digital experts,  some wire, cable and AC power experts are:

Keith Armstrong
Jim Brown
Neil Muncy (RIP)
Ralph Morrison
Henry Ott
Bill Whitlock

We are working with Mr Armstrong at the moment at work...

I don't do just digital, I have spent the last 30+ years of my career steering all sorts of signals from a to b, with signal integrity and EMC always a concern, as well as timing etc.

The only person I don't recognise on your list is Neil Muncy. I would also add Tony Waldron...

http://www.audioemc.co.uk/wp-content/uploads/2014/04/Pages-from-HFC_issue33-4-Waldron-EMC-short.pdf

http://www.nutwooduk.co.uk/archive/Old_Archive/021122.htm

Can't find part 1 online, I have it as aPDF somewhere.

Here's a little nugget I learned from the microwave guy's that stood me in good stead over the years for noise...

If you have an oscillator, place the power supply on the rear of the board, directly under the osc. This allows you to directly supply power to the osc. power pin with the minimum of copper, usually a short stub of track and a pin fro through hole osc,s. or a via for SMC. Use a good small LDO regulator and pi filtering on the main supply coming in. Decouple the device on the osc side with a small COG/NP0 cap, paralleled with a larger (10X+) X7R cap, in the smallest packages you can get, next to the pin.

Why is this important for noise... If you run the osc. of the main 3v3 supply (or other supply used by the device being clocked) then any detrimental effect the clock has on the power draw will capacitively couple through the power plane to the ground plane,  as the clock is the controlling switch its noise can couple to the rest of the circuit and the delayed switching of other devices can couple back to the clock... With a small localised supply the pi filter (works both ways) keeps the two noise sources separate, whilst the minimal amount of copper for the actual positive supply minimises the capacitive coupling, one of the main coupling methods for high frequency noise. If I was doing say a 21 bit high frequency DAC for some funky circuit this is how I would do it. It's not something I have made up, but a technique I have learned from those more knowledgeable than me who work in the dark arts of electronics... (thats RF and microwave, not audio)

Of course I am just a troll so ignore my comments...

 

[sandyk]

23 minutes ago, marce said:

It's not something I have made up, but a technique I have learned from those more knowledgeable than me who work in the dark arts of electronics... (thats RF and microwave, not audio )

 

 Very few members would be likely to dispute your qualifications and expertise in areas that you specialise in, other than  Audio.

[marce]

But I do audio, have done for years, mostly pro and mil audio stuff, hearing protection, mil comms. pro audio, a some commercial, mainstream, a few extended audio projects (animals other than Audiophiles who can hear KHz) then there is the far out stuff, but at the end of the day, it's all analogue, digital, RF, microwave or DC, they ALL follow the laws of physic's.

Oliver Heaviside worked out the basic equations for signal transmission about 1870ish, based on Maxwell's equations, a few years later and we still use these basic rules, WHY?

[sandyk]

22 minutes ago, marce said:

But I do audio, have done for years, mostly pro and mil audio stuff, hearing protection, mil comms. pro audio, a some commercial, mainstream, a few extended audio projects (animals other than Audiophiles who can hear KHz) then there is the far out stuff, but at the end of the day, it's all analogue, digital, RF, microwave or DC, they AL

You may do Audio, but as far as Hi Fi goes, you are way, way  behind a large number of CA. , and I would also say DIY Audio members.

I suppose that you haven't  even yet got around  to upgrading the PSU for your ENTRY LEVEL SBT ?