Beware of Snake Oil & Blind Belief!

[Guzzista]

At the outset I would like to state that the following experience is real and the product mentioned is available for testing.......

 

Some years ago when I made a serious upgrade of my Hi-Fi system a good friend of mine told me about a product he just purchased and recommended it to me, it was a sort of powerbox conditioner with a power board attached to plug in my components, I accepted his advice and ordered one.

 

For all of this time I have been listening to my equipment not knowing any different. that is to say quite happy, until this afternoon.

 

The same friend dropped in and the first thing he asked me was "do you have a short extension cord?" why I asked and he explained what had happened with his Hi-Fi earlier today. While adding a new CD transport he unplugged all his gear as one would, then when the new CD transport was booted up the LED screen scrolled through a message........ "power supply is 'out of phase'..."

 

He then bypassed the powerbox, the warning signal on the CDP went away and, the sound reproduction was seriously improved. We did the same at my home, I replaced the offending product with a simple Kambrook power board and? yep I found new sounds in my recorded music, for all this time my good equipment and more recently my new TT were being supplied source power in reverse phase!

 

I don't have to tell the Choir how much my music sound reproduction has improved........

 

"Buyer Beware!"

 

 

Edited December 7, 2018 by Guzzista

[audiofeline]

It would be interesting to dismantle this device and see if there is anything inside it.

[andyr]

50 minutes ago, Guzzista said:

While adding a new CD transport he unplugged all his gear as one would, then when the new CD transport was booted up the LED screen scrolled through a message........ "power supply is 'out of phase'..."

 

He then bypassed the powerbox, the warning signal on the CDP went away and, the sound reproduction was seriously improved. We did the same at my home, I replaced the offending product with a simple Kambrook power board and? yep I found new sounds in my recorded music, for all this time my good equipment and more recently my new TT were being supplied source power in reverse phase!

 

Not so much "out of phase" - as it's AC - but simply that the output sockets of this 'power box' (or the power board attached to this device, which you mentioned) have 'neutral' swapped with 'live'.  This can be a problem for power transformers, due to capacitative coupling between primary and secondary windings - and, yes, it affects the sound you hear! 

 

However, as I guarantee mfrs do not always connect the primary winding on the power transformer(s) the optimal way round ... some equipment (if it is connected the 'wrong' way round) could actually sound better using the power box.

 

What you need to do is have an electrician mate make up a short extension cable which deliberately has neutral swapped with live.  Then try it on each piece of your equipment in turn ... and see if your sound improves.  Those components which sound better with this 'reversed' extension cord have their power transformer(s) connected the wrong way round - so you should take them to a tech, to have the power transformer primaries reversed at the IEC socket.

 

I test power transformers for correct orientation on every mains-powered item I make.

 

Andy

 

[Guzzista]

2 minutes ago, andyr said:

 

Not so much "out of phase" - as it's AC - but simply that the output sockets of this 'power box' (or the power board attached to this device, which you mentioned) have 'neutral' swapped with 'live'.  This can be a problem for power transformers, due to capacitative coupling between primary and secondary windings - and, yes, it affects the sound you hear! 

 

However, as I guarantee mfrs do not always connect the primary winding on the power transformer(s) the optimal way round ... some equipment (if it is connected the 'wrong' way round) could actually sound better using the power box.

 

What you need to do is have an electrician mate make up a short extension cable which deliberately has neutral swapped with live.  Then try it on each piece of your equipment in turn ... and see if your sound improves.  Those components which sound better with this 'reversed' extension cord have their power transformer(s) connected the wrong way round - so you should take them to a tech, to have the power transformer primaries reversed at the IEC socket.

 

I test power transformers for correct orientation on every mains-powered item I make.

 

Andy

 

andyr

 

Regardless of your advice, I know what I hear, I am not prepared to waist good money after bad on a piece of equipment that is incorrectly constructed. It going in the bin as a lesson learned! I don't think Nelson Pass or Symaudio ever design equipment to accommodate power supplies that have the neutral and live inputs reversed.

 

And that's that, its going where crap belongs.

 

 

[sir sanders zingmore]

1 hour ago, andyr said:

What you need to do is have an electrician mate make up a short extension cable which deliberately has neutral swapped with live.

Sounds “potentially” risky. Is that something a qualified electrician is even allowed to do ?

[Addicted to music]

3 hours ago, Sir Sanders Zingmore said:

Sounds “potentially” risky. Is that something a qualified electrician is even allowed to do ?

No.....

 

and  I seriously will never recommend to do so or advise anyone to perform a dangerous practice.     

[andyr]

8 hours ago, Guzzista said:

andyr

 

Regardless of your advice, I know what I hear, I am not prepared to waist good money after bad on a piece of equipment that is incorrectly constructed. It going in the bin as a lesson learned! I don't think Nelson Pass or Symaudio ever design equipment to accommodate power supplies that have the neutral and live inputs reversed.

 

And that's that, its going where crap belongs.

 

You mis-understand me.

 

It's not a matter of bad design - merely bad implementation.

 

Nelson Pass's power supply - and every body else's - is designed correctly.  The 'active' goes through the fuse - as per electrical standards.  The issue - which, as you've experienced - affects the sound ... is whether the primary winding of the power transformer is optimally oriented wrt to 'active' and 'neutral'.

 

The power transformer will work quite happily, whichever orientation it has - and will meet electrical standards, connected both ways.  However, as you've experienced ... one way round will sound better.

 

Andy

 

[sloper]

It will sound great till it kills you.

l wouldnt use that electricain to change a light bulb.

 

regards Bruce

[marten]

14 hours ago, andyr said:

 

This can be a problem for power transformers, due to capacitative coupling between primary and secondary windings - and, yes, it affects the sound you hear! 

 

Andy

 

 

Just trying to improve my understanding here - how does the AC behaviour of the transformer affect the audio signal on the DC side of an amplifer or preamp ? 

The 240v AC supply is converted down to the region of, say,  12v to 40v DC by a (presumably high quality) AC-to-DC converter/rectifier, and the audio signal is only handled on the DC side.

 

Is it because the AC-DC converter module struggles to produce pure "flat-line" DC, or some other reason ?

 

Edited December 8, 2018 by marten

[blakey72]

Not good at all. Was it expensive?

 

[andyr]

1 hour ago, marten said:

Just trying to improve my understanding here - how does the AC behaviour of the transformer affect the audio signal on the DC side of an amplifier or preamp ? 

 

Just focus on the power transformer which, as you say, converts 240v on the primary to (generally 2x) secondary windings at anywhere from 20v AC to 50v AC.  Then the rectifier bridge and smoothing caps produce a nice flat DC voltage of anywhere from +/- 28v DC (1.4 x 20v) to +/- 70v DC (1.4 x 50v).

 

The primary winding has an 'in' wire and an 'out' wire and there is a difference in the sound of the components which the PS is driving, depending on whether:

• the 'in' wire is attached to the 'active' side of the mains and the 'out' wire is attached to the 'neutral'
• ... and the reverse, where the 'in' wire is attached to the 'neutral' and the 'out' wire is attached to the 'active'.

This was first described 20 or 30 years ago in a US book called "The Wood Effect" written by, I think it was, Clark Johnsen.  The reason behind this sonic difference, I'm told by my amp-designer friend Hugh Dean, is to do with 'capacitative coupling' between the primary and secondary windings - but why this should affect the sound ... I have no idea!

 

But as, Hugh, I (and now the OP) know, it does affect the sound.

 

Andy

 

Edited December 8, 2018 by andyr

[Monkeyboi]

15 hours ago, andyr said:

 

Not so much "out of phase" - as it's AC - but simply that the output sockets of this 'power box' (or the power board attached to this device, which you mentioned) have 'neutral' swapped with 'live'.  This can be a problem for power transformers, due to capacitative coupling between primary and secondary windings - and, yes, it affects the sound you hear! 

 

Andy

 

a.c can certainly be out of phase.  The signal going into your speakers is alternating current (a.c.) and we all know what the effect is if one speaker is reversed (180 degrees out of phase) relative to the other(s).  The mains is no different and reversing active and neutral wires will have exactly the same effect in terms of phase, however the degree this is likely to affect the sound is a matter of circumstance and question.

 

IME out of phase mains power connections to power amplifiers where high currents are involved and the d.c. ripple is more likely to be higher there is a difference.  With low power devices the effect is generally less pronounced.  With switch-mode supplies, reversing the active and neutral connections is IMHO definitely not recommended although it probably happens more than often with US, Japanese and some other Asian countries that use either 2 pin round or flat mains plugs without a third pin for earthing.

 

Cheers,

Alan R.

[Guzzista]

59 minutes ago, blakey72 said:

Not good at all. Was it expensive?

 

Around $500.00 If I remember correctly.

 

[Guzzista]

16 hours ago, audiofeline said:

It would be interesting to dismantle this device and see if there is anything inside it.

I have done this and taken a picture of the inside, I'm reluctant to post it though, I'm cautious of litigation.

[Monkeyboi]

1 hour ago, blakey72 said:

Not good at all. Was it expensive?

 

Gee, if I was an American citizen I'd be more worried about Trump snake oil.  A little like his "alternative facts"????

 

[Monkeyboi]

1 minute ago, Guzzista said:

I have done this and taken a picture of the inside, I'm reluctant to post it though, I'm cautious of litigation.

If there is a visible branding just put the image into an image manipulation program and "fuzz out" the brand.  However having said that, if the product has the active and neutral connections reversed it doesn't comply with Australian standards and should either be withdrawn from the market or recalled / replaced with a compliant model.

 

That's why you can no longer buy those old triangular shaped double adapters from the 70s.  One side had the active and neutral reversed due to the way they were manufactured back then.

 

Cheers,

Alan R.

[Guzzista]

12 minutes ago, Monkeyboi said:

If there is a visible branding just put the image into an image manipulation program and "fuzz out" the brand.  However having said that, if the product has the active and neutral connections reversed it doesn't comply with Australian standards and should either be withdrawn from the market or recalled / replaced with a compliant model.

Cheers,

Alan R.

 

[andyr]

1 hour ago, Monkeyboi said:

a.c can certainly be out of phase.  The signal going into your speakers is alternating current (a.c.) and we all know what the effect is if one speaker is reversed (180 degrees out of phase) relative to the other(s).  The mains is no different and reversing active and neutral wires will have exactly the same effect in terms of phase, however the degree this is likely to affect the sound is a matter of circumstance and question.

 

IME out of phase mains power connections to power amplifiers where high currents are involved and the d.c. ripple is more likely to be higher there is a difference.  With low power devices the effect is generally less pronounced.  With switch-mode supplies, reversing the active and neutral connections is IMHO definitely not recommended although it probably happens more than often with US, Japanese and some other Asian countries that use either 2 pin round or flat mains plugs without a third pin for earthing.

 

Cheers,

Alan R.

 

Thanks for pointing out my error, Alan.    Your graphs present the issue quite simply.

 

Andy

 

[t_mike]

Is that a solder only earth?

[blakey72]

2 hours ago, Guzzista said:

Around $500.00 If I remember correctly.

 

Oh. Could be worse. I think power is the least of our worries in Australia.

[Monkeyboi]

55 minutes ago, t_mike said:

Is that a solder only earth?

Better than just twisted and not soldered.  Anyhow IMHO it's a dog's breakfast at best.  Cheap and nasty assembly.  I wouldn't use it, but that's just my opinion.

 

Cheers,

Alan R.

[Bronal]

I wonder if your 'good friend' is still your good friend...

 

He certainly had a lot of front to persuade you into buying that device and then come back to tell you it was no good.  I hope he had the good grace to compensate you in some way for his bad advice.  But I doubt it.

 

I've been led by the nose like that.  It's a bitter pill to swallow when you know you've spent a lot of money for nothing, especially when what you bought looks like it was made as part of a year 7 project.

[bzr]

Listen to it, if it sounds good buy it. Don't start playing the yellow card about remorse or bad judgment! Seriously??

[andyr]

3 hours ago, Monkeyboi said:

That's why you can no longer buy those old triangular shaped double adapters from the 70s.  One side had the active and neutral reversed due to the way they were manufactured back then.

 

Cheers,

Alan R.

 

I never knew that, Alan! 

 

Thanks for the input - I will have to carefully examine the few triangular double-adapters that I still have - so as to mark the 'correct' side.

 

Andy

 

[andyr]

53 minutes ago, Bronal said:

I wonder if your 'good friend' is still your good friend...

 

He certainly had a lot of front to persuade you into buying that device and then come back to tell you it was no good.  I hope he had the good grace to compensate you in some way for his bad advice.  But I doubt it.

 

I've been led by the nose like that.  It's a bitter pill to swallow when you know you've spent a lot of money for nothing, especially when what you bought looks like it was made as part of a year 7 project.

 

You're taking a pretty harsh view, B. 

 

If the OP's friend had actually made the device - and was just flogging it to him ... then, yes, that is reprehensible.  But if he had got sucked in and bought one himself - and thought it did good (which is how I read the OP's post) - then, naturally, he would suggest to his friend that it was a good thing to buy.

 

I don't think compensation is at all appropriate - after all, the OP didn't have to take his friend's advice.

 

Andy

 

Edited December 8, 2018 by andyr