Clean Power

[manisandher]

Maybe not stupid when you think it is a false alarm..

Yes I was asking whether it might just be a false alarm - the 'noise sniffer' might not be designed for a balanced setup.

Is it allowed to know what this was ? I mean, maybe I am going to read that article, but reading my own posts ?

Yes, referring to 'Peter's long post' is a bit like referring to Berlusconi's gaffe. I meant this:

Hook up your DC Voltmeter to the two ground references. You should see something. Now, start switching on house devices like phone adapters or motors or possibly amplifiers and the like. Watch the DC Offset change with it.

Now envision that this DC Offset mangles with at least your house ring ground reference. So, mid point e.g. goes up, and think about the part of the (hot point) wave above zero (which should be lower now in amplitude ) and the one under it (should be higher). Here you are turning that sine into something else.

In the mean time your AC output changes too. I never looked at it on the analyser, but while net the result should be the same, it won't because of the wave shape and let's say (for easily envisioning it) clipping at one side.
This all is about your consuming devices fireing back to the mains because of they changing the ground reference.
It may not be an official thing, but this is how I once could look at it. So, that consuming device is not a "balanced device" like in "it draws from both the phases separately" (see earlier posts about this - the 115v/115v thing) but as how I look at it, it will draw the ground towards "itself". So, where ground is to be 0V (which is a virtual thing always, but works for the physics in order) and a device is consuming the 230V, the ground goes up by, say 5V. I know, for AC this can't work, but I think something like switching power supplies ay use the positive side of the wave only or more than the negative, which depends on how the AC/DC conversion is done.

Attached are are a couple of snippets from the article.

Mani.

[PeterSt]

Wow Mani. I only read the first part (will read on later) to see that I made up something which more knowledgable people already knew. But as I told earlier, for me this is just empirical finding, trying to make up the story of why around that.

Now I will read further. Thanks for posting this !
Peter

[stefanobilliani]

So in real life , If I use in the practice a transformer ( like in fig.6) from the mains to split the 220V in to two phases (115-0-115) , I can connect the PC to it for example ( included the new ground )  and all works pretty fine.
The only thing I see is a Voltage between the Transformer ZERO and the house earth . This voltage is about 70Volts , which goes to about 10V with a current flow in the order of uA .

If we want to be safe , and sure to protect our audio inputs againts that , it is better to let flow that little current -OR - connect all the HI-FI gear to the transformer .

Just my thoughts .

[manisandher]

The only thing I see is a Voltage between the Transformer ZERO and the house earth . This voltage is about 70Volts , which goes to about 10V with a current flow in the order of uA .

In my case, the DC voltage between teh transformer zero (bonded to my dedicated earth) and the house earth is only 0.25V. The AC voltage is 0.4V. I can live with 100-200 nA.

Mani.

[stefanobilliani]

The only thing I see is a Voltage between the Transformer ZERO and the house earth . This voltage is about 70Volts , which goes to about 10V with a current flow in the order of uA .

In my case, the DC voltage between teh transformer zero (bonded to my dedicated earth) and the house earth is only 0.25V. The AC voltage is 0.4V. I can live with 100-200 nA.

Mani.

Thanks for pointing out that . I was talking of AC voltage , but as I say it carries very little current and it can be reduced very easily .
Of course my example is a diy experiment without a dedicate earth .... ok

s

[manisandher]

I spent a long evening yesterday comparing various AC configurations (house AC, PurePower2000, 5KVA balanced in all permutations). I'll share my views when I have more time. But I just want to quickly share something with Nick.

I went ahead and ordered a 3kva transformer from Airlink today.

The Airlink seems to work best with an AC cable with a shield. I use Belden 83803 - a pig to work with but easily available on eBay and reasonably cheap. Connect the shield to earth at both ends.

Mani.

[Nick]

I spent a long evening yesterday comparing various AC configurations (house AC, PurePower2000, 5KVA balanced in all permutations). I'll share my views when I have more time. But I just want to quickly share something with Nick.

I went ahead and ordered a 3kva transformer from Airlink today.

The Airlink seems to work best with an AC cable with a shield. I use Belden 83803 - a pig to work with but easily available on eBay and reasonably cheap. Connect the shield to earth at both ends.

Mani.

Mani,

i'm looking forwards to hearing the outcomes of your tests.
Thanks for mentioning of the Belden cable. I was concidering a rewire of the whole system on the Mains side and had spotted this cable. With your posertive experiance I have the confidence now to just go ahead and do it.

Also thanks for helping with my questions about the AirLink transformers, I am really happy with what it has done for my system .

Cheers,

Nick.

[Nick]

This topic has been really helpful to stuff that I have had to look into recently and I wanted to post some impressions on the balanced mains power transformer that I have recently installed.

A recent visit by Paul's (Scroobius) to my place has helped to highlight a [big] "problem" with my system which has been holding back sound quality for a very long time. Then a return visit to Paul's place absolutely confirmed the problem and rather excitingly for me, totally reset what I consider to be my reference sound (wow Paul's system is good). During our chats Paul recommended trying balanced mains power and this became the get well step.

As a side note, it is turning out the at the "problem" is a compound one caused by a number of factors (so no "silver bullet" single fix  ). Everything in the system is coming under scrutiny.  Steps so far that have really helped are installation of balanced mains power, and the discovery that using my laptop to RIP CDs has lead to very substandard RIPed WAVs. Now that I have the Balanced mains it is easily allowing me to hear the difference between Laptop and PC RIPs easily so another part of the "problem" has been solved.

I guess that the impact from installing balanced mains power is going to vary depending on how poor the starting mains supply. I must have had poor mains quality because the change is really large here. In its fact difficult to fathom just how much better the sound has become !

Prior to installing I wanted to get the safety aspect of going balanced addressed. The AirLink Model that I went for does much of this by virtue of having primary circuit breakers and most importantly for me the RCD on the output phases installed as standard. In addition I will be fitting secondary fuses internally on all equipment that is connected to the Balanced power to ensure that what was formally the neutral wire has some fault protection within each component. I am no electrician so these measures my only be a starting point but I feel safer using balanced mains with them then without.

This is the unit which is a smaller 3kva version of the 5kva models that that Mani uses, the 3kva model has three pin main plugs installed making output wiring a little simpler than the bigger unit. Build quality is "industrial" but given the price very good, the unit makes virtually no humming sound you have to have your ear right to the case to hear anything at all and then only occasionally can you catch it making any sound. Delivery took just two days.

http://www.airlinktransformers.com/standard_balanced_power_supplies/61-BPS3110S.html

So the impact of the system on sound quality. Well sound is has improved EVERYWHERE, perhaps most importantly a nasty layer of hash and confusion in the sound has been removed throughout the performance right from lows through to highs. This has creatated a much firmer and more understandable foundation for the music to be built on with a much lower noise floor. Transients are better defined and more accurate in their weight. For the first time, in a very long time, highs could almost be described as sweet, with understandable rhythms easily coming across in percussion lines (this was also improved by the discovery that my laptop RIPS are flawed). Mid range is solid less confused has better prominence and improved air and focus between the speakers. Voices, guitars, strings, horns and drums are better reproduced with more colour weight snap and delicacy where appropriate.

My comments are in the context of the balanced power output earth being connected to the household mains PE. I have not setup a dedicated low resistance earth (using earth rods etc) but this may come later.

I was not really that much of a believer in mains conditioning before this and perhaps still don't really subscribe to the conditioning approach of many of the single phase solutions, but the Balanced approach is such a simple one, providing isolation, noise cancellation, and possibly more stable ground reference. I am hooked, this rather industrial looking box has found a place at the heart of my music system.

There are still further "problems" to address for me but I think the mains component is now done, and one strep closer the the sound I fell in love with a few weeks ago whilst at Paul's.

Nick.

Ps these impressions are with about 20 hours on the transformer they are supposed to improve quite a lot with some burn in.

[stefanobilliani]

hi Nick, could you please poste a draw or schematic of your new balanced connection in power supply   so that we can have a reference? If possible.   stefano

[manisandher]

I've got a few minutes before my flight, so thought I'd quickly chime in.

So the impact of the system on sound quality. Well sound is has improved EVERYWHERE, perhaps most importantly a nasty layer of hash and confusion in the sound has been removed throughout the performance right from lows through to highs. This has creatated a much firmer and more understandable foundation for the music to be built on with a much lower noise floor.

Yes, this is pretty much exactly how I would describe going to balanced AC in my system. As a result, in my system, the depth of the sound stage is really improved - certain sounds now come from way back behind the speakers. There is nothing at all in your face.

However...

The PurePower2000 provides an even more drastic improvement. It's hard to describe, but with it I'm no longer getting just a nice clean sound, I'm getting music. An acoustic guitar no longer sounds like it's made out of cardboard. It now resonates and 'sings', just like my own Martin (when someone who can actually play a guitar plays it, i.e. not me). I really, really don't want this to sound like an advert for PurePower - they are bloody expensive and may not work out well for everyone. Indeed, mine has been gathering dust in my cellar for the last 12 months because I decided I preferred the sound without it. But then I tried plugging everything into it, including the PC, and voila.

So I now how the following AC setup:
100A dedicated line -> PurePower2000 -> 5KVA balanced transformer (with dedicated earth on output) -> shielded/screened wiring

The biggest bang-for-the-buck is definitely the 5KVA transformer. But having heard what the PP2000 does, I can no longer with without it. Indeed, I've just ordered a new PurePower+3000. (Of course this is just crazy - quite frankly I could have paid my bloody mortgage off with all the money I've spent on this hobby.)

Mani.

[Nick]

The biggest bang-for-the-buck is definitely the 5KVA transformer. But having heard what the PP2000 does...

Dam, why do I read these things ? now I want a PurePower but I just looked at the price !

Nick.

[Scroobius]

Wow I was trying to justify the cost of a balanced transformer I had not even started to think about a Purepower!!!!

P

Hey Nick - glad to hear your balanced Tx is sounding good sounds like a good enough reason to come up for another listen!! (Oh yes and another run out in the Ultima ha ha)

Also do you still have your "balanced earth" connected to house earth? as balanced operation cancels reactive currents appearing on the secondary your "balanced earth" should be nice and clean - it seems a shame to connect it to a dirty old house earth. Well maybe who knows how dirty the house earth is? - but anyway I reckon it would be worth lashing up an earth in the garden even on a temporary basis to see how it performs.

I suppose a concern is always the possibility of a significant difference in voltage appearing between the dedicated earth and the house earth - at least Mani's is very small but who knows. It would be interesting though.

Hey Mani - have you tried house earth versus dedicated earth in respect of SQ?

[Nick]

Wow I was trying to justify the cost of a balanced transformer I had not even started to think about a Purepower!!!!

P

Hey Nick - glad to hear your balanced Tx is sounding good sounds like a good enough reason to come up for another listen!! (Oh yes and another run out in the Ultima ha ha)

Paul hi,

I was going to pm you, yes it would be great to try balanced power in your system. My unit or Mani's (or both ha ha). Could the best get better ? Let me know the dates you are thinking of.

Speak soon,

Cheers,

Nick.

[Scroobius]

Interesting extract from the Equitech site and of particular interest to Nick who has a 3-phase supply to his house:

"The level of interference created when a three-phase wye system is split up and used as three single-phase circuits is truly something to behold. For example, as much as 20% (or more) of the power used by fluorescent ballasts is reflected back onto the power grid in the form of reactive or harmonic currents -- now that’s a lot of distortion. In the late 80’s, a 40-plus-story office building in Los Angeles actually burst into flames because of these reactive currents. Incredibly, the origin of the fire was determined to be from excessive harmonic distortion in fluorescent lighting circuits which created a high-frequency current overload and literally a meltdown of the electrical wiring system. The First Interstate Bank fire in Los Angeles in May of 1988 was the event dubbed by the media as "The Towering Inferno" a la the Hollywood movie. Codes were adapted to remedy the fire danger, but the noise problem itself was never completely resolved."

more here  http://www.equitech.com/articles/enigma.html

P

[Nick]

Interesting extract from the Equitech site and of particular interest to Nick who has a 3-phase supply to his house:

"The level of interference created when a three-phase wye system is split up and used as three single-phase circuits is truly something to behold. For example, as much as 20% (or more) of the power used by fluorescent ballasts is reflected back onto the power grid in the form of reactive or harmonic currents -- now that’s a lot of distortion. In the late 80’s, a 40-plus-story office building in Los Angeles actually burst into flames because of these reactive currents. Incredibly, the origin of the fire was determined to be from excessive harmonic distortion in fluorescent lighting circuits which created a high-frequency current overload and literally a meltdown of the electrical wiring system. The First Interstate Bank fire in Los Angeles in May of 1988 was the event dubbed by the media as "The Towering Inferno" a la the Hollywood movie. Codes were adapted to remedy the fire danger, but the noise problem itself was never completely resolved."

more here  http://www.equitech.com/articles/enigma.html

P

OMG !

 I'm going to keep the fire extinguisher near by ! I'm starting to think three phase is for industrial plant not hifi ha ha.

What a great article on the equitech site, fascinating and really makes sense when you think about it. I think setting up a dedicated earth is going to be next. I found a bespoke earth in the flower bed next to the front door. The chap that owned the house was into hifi so I'm wondering if he put it in. I think I will have to get the garden spade out this week end to see what's happening. I never thought doing the garden would have the possibility of improving sound quality ha ha.

Nick.