Power conditioning: how did you choose the best approach for your system?

[jabbr]

3 hours ago, PeterSt said:

So this is power conditioning of a real kind because you will be trying to avoid ground loops. And antenna working with it (radiation at first because something is wrong and a receptor secondly, elsewhere. Usually not your toaster but your DAC or something).

 

Yes! So this sums up what is needed:

 

1) good high quality/low capacitance isolating transformers break ground loops and “leakage” currents. 

2) common mode/EMI filters to reduce antennae effects as well as EMI projection along the USB (and other cables) 

3) differential signaling (ground loops and reduce differential mode noise)

[jabbr]

5 hours ago, Ralf11 said:

here is Nelson Pass's article I was thinking of earlier:

 

https://www.passdiy.com/project/articles/power-supplies

Quote

 Get at least 15 pounds of amplifier for each thousand dollars spent.

 

[jabbr]

1 hour ago, Ralf11 said:

 

 

it is the height of stupidity to assume that an ameuter DIYer can tinker their way into a result better than the best engineers in the business

 

 

There are two sides to this: 

 

On one  hand “tinkering” without engineering/physics/measurements and established design methodologies is  unlikely to better an actual design. Swapping in a magic capacitor or clock etc does not equal actual design. Indeed can be worse because the relevant variables haven’t been accounted for. 

 

That said, the very best engineers have been known to hang out at DIYAudio and a DIY who employs actual design methods can build a component that would otherwise be cost prohibitive. 

[jabbr]

7 hours ago, shtf said:

Getting back to variations of line conditioning, including superior vs inferior.  I could probably take a reasonably humble but well-thought-out playback system retailing between say $45k and $60k (including superior line conditioners) and have one of the top 5 or even top 3 most musical exhibiting rooms at any given high-end audio show just because of the superior line conditioners.  Oh, that’s right.  I already did that.  Multiple times.  And that was only because I was employing superior line conditioners since my own product takes weeks before the magic even begins to kick in.

 

“Your own product”? You seem to say  that you have incorporated your own product at a high end audio show. What?

 

As I’ve said there are 2 components to s reasonable power “conditioning” system. There seems to be a bunch of crap talked about regarding esoteric and expensive power conditioning that has zero merits. We have labs that depend on clean power to make extremely sensitive measurements — we use the techniques I described (a) transformers (b) EMI filtering/mitigation — all else is BS

[jabbr]

5 hours ago, PeterSt said:

The real "sport" is in making it unnecessary. Ask @jabbr, he owns a piece of it (could be a surprise to himself).

Now why do I not like DSD ...

 

Peter, if you’d care to publish your schematic, we can discuss!

 

I think “ground earth” reference is the most misunderstood concept in all of audio.

 

Hint: it’s purely a safety issue. 😉 Consider this: in Donald Trump’s jet, the audio system has gold plated shielding around pure silver conductors. The grounding box has a solid gold bar — what is the earth reference? How is the SQ affected by altitude? 😂😂😂

[jabbr]

42 minutes ago, PeterSt said:

 

a. it is a secret, b. you won't find it, because c. it is not there. And also no cap in the output.

But if all is right you know about the procedure to get the DC Offset right.

 

What you won't know (because before your times) is how this all was set up at first, and next failed at 110V (USA). Then half of the UK failed (they have the most crazy power grid systems (towards the homes) - IIRC 5 different of them).

Two months of struggle later, and all was solved for everywhere.

 

Wait, did I just imply that it must be grid related ?

nahhh

 

 

 

So I have a sweet Equi-tech “Model Q” balanced isolation transformer — I also have several Topaz in several sizes. Assuming your electronics are fed by the Equi-tech ... the effect of the power grid, or house wiring, or quality of my earth ground  is exactly how much over zero?

 

Hint: the Equi-tech has good protective circuits on a great low capacitance and very solid transformer — nothing at all magical

 

Ok now if you’ve got EMI coming in from your fridge then get a good filter — the ones the ham radio guys use — these are also cost effective 😉

 

 

[jabbr]

6 minutes ago, sandyk said:

 

Many of the Amateur Radio guys also use vastly improved earthing too.

 

The professional radio guys tend not to use earth grounds, eh @marce 

[jabbr]

1 hour ago, sandyk said:

 

 I am not a Ham Radio guy, but if it wasn't for the Amateur Radio guys many years ago, we wouldn't have S/W radio, long distance communications, TV, moon bounce etc.  capabilities and more than likely no Pro radio guys either.

 

I am alluding to the fact that aerospace radio tend to be professional, and obviously works and obviously has no earth ground. The need , or not, for earth grounding of ham radio antennae is a topic beyond this forum. Again, my impression that the role of earth grounding in audio circuitry (beyond safety) is perhaps the most misunderstood topic on this forum.

 

Here is an exercise (leave safety concerns about prying fingers aside): design an audio system with no earth ground: assume 120V balanced AC power input i.e. + = 60V AC and - = phase inverted 60V AC ... can you do it?

[jabbr]

2 hours ago, Ralf11 said:

 

maybe it is time to discuss proven or claimed sonic benefits of adding isolation transformers, balanced power, etc. ...

 

 

Reduction in ground loops — if your leakage don’t stink you are good  

[jabbr]

25 minutes ago, Ralf11 said:

but what is the effect on sound quality ??

 

or is that a cross-sensory comment?

I guess that if you decrease hum and other noise from ground currents eg crackles, that you improve the overall dynamic range of the reproduced sound?

[jabbr]

10 hours ago, Ralf11 said:

maybe it is time to discuss proven or claimed sonic benefits of adding isolation transformers, balanced power, etc. ...

 

Let me try to explain a different way:

 

My goal on the digital side of the system is to deliver the bits to the DAC in a bitperfect fashion and without noise. 

 

I am not specifically looking for a power supply “sound” or transformer “sound” rather to supply clean power, to reduce both differential and common mode noise. If particular I want to keep common mode noise out of the system because this can be trickier to eliminate. 

 

So I look at the inputs to the system and look to minimize noise entering the system via its inputs: both power and signal. This also means keeping the system as simple as reasonable. I don’t listen for “SQ” of power supplies, rather to reduce problems such as hum & fuzz & crackles. I don’t listen to different power supplies, rather select something good for the purpose and use it. 

[jabbr]

5 minutes ago, PeterSt said:

I understand the former. But I have never seen anything like the latter. Such a thing does not happen in a power supply. At least not that I can tell.

 

Specifically ground loops and leakage currents (same thing really) —- no doubt you’ve heard one! No doubt you fixed it decades ago 😂

[jabbr]

11 minutes ago, PeterSt said:

But now I don't know how that relates to isolation transformers. Oh, we can imagine something, but ... not really.

 

??? I’m sure you know how isolation transformers work but I’ll explain for folks listening in the sidelines.

 

The  noise from your fridge etc sails across a cheap SMPS which has a tiny transformer and s substantial amount of interwinding capacitance —- at frequencies >0 the current passes through the capacitance and back along the ground forming a circuit. The more capacitance, the more current flows across the transformer —- this is leakage current which is essentially a ground loop.

 

An isolation transformer has very low interwinding capacitance and thus minimizes these AC currents emitted by your fridge etc — it this blocks these ground loops by cutting off the circuit. 

 

Remember that all currents flow in circuits — including that 5mV noise — noise travels along parasitics — an isolation transformer blocks these currents and hence “rejects” the noise. 

[jabbr]

Star grounding: why? Because the inductances are similar! Noise is AC!

 

You don’t want to unintentionally create a low inductance path and shunt noise into the circuit along parasitics!

[jabbr]

1 minute ago, PeterSt said:

 

through air

No isolation transformer stops that. It may actually make it worse (although I could never prove that).

Remember — all currents form a circuit! No exceptions!

 

You are referring to common mode noise. Don’t build an antenna 😉

[jabbr]

6 hours ago, PeterSt said:

 

Remember what I said earlier on: DO build an antenna. A dummy one. Disco light or something. Haha.

But I have no knowledge on antennas (or antennae if you want). So how does my disco light captures the signal before by (e.g.) DAC does. Just put it in the right path(way) ?

Shielding where it shouldn't go after all ?

 

 

https://science.howstuffworks.com/faraday-cage.htm

[jabbr]

On 6/25/2019 at 12:11 PM, Ralf11 said:

e..g. better spatial localization of instruments, finer detail, better low end definition, larger soundstage

 

 

Sure all of that! 

 

I think we are all looking for better realism, the sense of being there. Looking for the electronics to just disappear and just listen to the music. Transparency. 

 

Let's say you were designing a lab in your home to make some very sensitive measurements: you probably use an iso transformer (balanced or not), you'd probably use those nice slate benchtops and might vibration isolate them if you are being really sensitive, you might even build a faraday cage into the walls if you are being really sensitive.

 

That's for electronics, now for music, you'd treat the walls and do room correction.

 

That's just the background, the canvas. To listen to music, we need to add music to this blank slate.

[jabbr]

8 minutes ago, PeterSt said:

 

No freakin' way. The walls not and might one have the idea that room correction is necessary ... backdoor solutions to inherent faults to begin with.

 

Funny, because I'd apply the "for electronics" right away.

 

We shouldn't be able to communicate a single word. 😫

 

To be clear:

 

First was the "canvas" for electronics ... blank slate on to which electronic devices are added

Second was the "canvas" for music ... blank slate on to which music is added

 

my approach. you may not need vibration isolation, you may not need isolation transformer, nor may you need a faraday cage in your environment, nor may you need room correction

[jabbr]

9 hours ago, marce said:

for dipole reference plane I believe, my mate at work is more into this stuff than me and goes on about his antenna's and their effect on domestic bliss... Amateur hams are a different breed!!!

http://www.hottconsultants.com/pdf_files/dipoles-1.pdf

 

😂 I was referring to the fact radios seem to work in space  

 

Hmm ... I wonder what the bass will sound like when they play the opening score to “2001” during the long Human Mars Mission ... do you think the SQ will be affected?

[jabbr]

23 hours ago, Ralf11 said:

but if you like your wooden box, you can keep your wooden box

 

Do you think that if I plug my electric charcoal lighter into it, it will make the food coming out of my grill taste better?

 

Grilled bass is a very good power supply for humans!

 

Alternatively if you like your scotch somewhat oaked?