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Mains Power and grounding


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Oops, this says it all.

 

Don't ground anything, the system works as is. If you feel tingles, then use a meter to check between the case of the amp and the ground in the power strip.

The power strip is OK, has overvolts protection that won't interfere unless there's an overvolts, unless it's been hit and needs to be tossed. Easy to tell, it smells. Do Euro plugs only insert the one way? Try reversing the connection, or at least make them all the same orientation. Connect the amplifier to the first connector after the cable connection of the power strip.

 

You need to decide if the CD player's analog out is better than the DAC. If it is, then only use the DAC from the Macbook and remove the coax from the CD player. Less is more :) If the coax is a better sound through the DAC, remove the stereo lead to the amplifier from the CD Player.

 

Toss the Toslink in favour of a USB with a switchable input to coax DAC to the amplifier if you want to spend money wisely would be a suggestion. Until there's a solution for the Mtech OSX driver issue try another DAC, perhaps a Chord, Musical Fidelity or a Vega both receive favourable mentions at CA.

Forrest:

Win10 i9 9900KS/GTX1060 HQPlayer4>Win10 NAA

DSD>Pavel's DSC2.6>Bent Audio TAP>

Parasound JC1>"Naked" Quad ESL63/Tannoy PS350B subs<100Hz

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Do you think that this additional coax connection from DAC to AMP may cause some issue here? Another thing, which I was considering is to use USB/SPDIF converter like BelCanto mLink to use USB - my DAC has USB with only redbook spec.

 

There's no need to make extra connections if they are worse than the other, keep everything lean. Time to update the DAC if it will only do redbook, a DSD only Schiit Loki goes for USD129? The ifi people have great DACs for low prices, the iDSD nano does everything, DXD, DSD, you name it.

AS Profile Equipment List        Say NO to MQA

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This weird zapping, by chance you have carpet ? it could be "Static" electricity, just wondering

 

It may be, but I don't think it's static electricity, touching anything else like my laptop don't make this feeling. It is not harmful, but thinkable what it is and if it can have any impact on the sound quality.

--

Krzysztof Maj

http://mkrzych.wordpress.com/

"Music is the highest form of art. It is also the most noble. It is human emotion, captured, crystallised, encased… and then passed on to others." - By Ken Ishiwata

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There's no need to make extra connections if they are worse than the other, keep everything lean. Time to update the DAC if it will only do redbook, a DSD only Schiit Loki goes for USD129? The ifi people have great DACs for low prices, the iDSD nano does everything, DXD, DSD, you name it.

 

It only does redbook, but only on USB input. SPDIF/Optical can do 24/96.

--

Krzysztof Maj

http://mkrzych.wordpress.com/

"Music is the highest form of art. It is also the most noble. It is human emotion, captured, crystallised, encased… and then passed on to others." - By Ken Ishiwata

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It may be, but I don't think it's static electricity, touching anything else like my laptop don't make this feeling. It is not harmful, but thinkable what it is and if it can have any impact on the sound quality.

 

If you have a DMM it's easily verified by reading any AC voltage between the outer of the devices RCA output socket and earth of a mains socket. The symptoms described are typical of many SMPS powered devices.

Some time back a member of another forum reported similar with a Graham Slee headphone amplifier using an SMPS plugpack. In that case, earthing the metal case got rid of the annoyance, and reportedly also resulted in an improvement described as like lifting a veil. Silicon Chip magazine even described a small device using only a couple of components to bolt on the metalwork of the offending device's case, with a lead going to a 3 pin mains plug's earth pin, with the other 2 terminals vacant. If anyone else is interested, please PM me for further details about this and another similar report re SMPS powered CD/DVD players.

 

Alex.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Do any power utilities actually do this ?

No. In the US they are installed by electricians, or a homeowner can do it himself. Not sure about the rules down your way, but I don't see why it would be any differen

Any connection of such a device at the main breaker device by the consumer would likely incur the wrath of the power utility if noticed. It is dangerous, and I can't imagine any licensed electrical contractor being party to this either.

Sorry, not correct. It's neither dangerous, nor does the utility care. It's installed on the customer's side of their service, the devices are designed to be installed at the breaker box, meant for the purpose, and can be installed easily without even turning all the power off. They simply connect to a two-pole breaker (turned off for installation) and ground. Here's a link to a product.

I do however agree with the bulk of what dc2bluelight is saying. Most commercial equipment needs further attention to the PSU area, including correctly chosen "snubbers" across the secondary windings of the power transformer as John Swenson has already described, and as he has suggested, that if done correctly this would help to rule out the need for expensive boutique power leads. Perhaps we are lucky in Sydney with our 240V AC 50Hz (typical voltage) but I don't know of any fellow DIYers who have felt the need for such drastic measures as taken by many U.S.A. C.A. members to overcome perceived mains power supply problems, other than perhaps trying to use SMPS devices on different circuits,(or avoid them if possible) and ensure the integrity of the mains earth in older houses. Most do however pay further attention to the PSU area of their own builds.

I appreciate your mention of the quality of the mains earth/ground. People assume that they have a good ground connection, only to find out the hard way they don't. That rod hammered into the ground by the service entry may not be as good as we hope it is. But a lot of how surge protection works depends on a good ground.

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No, the MOVs are in parallel with the mains. Filter chokes are in series though, and may do this if they are not adequately rated for the maximum current drawn.
Proper surge protection places an MOV in parallel with the mains, then one from each leg to ground. Common-mode surges are some of the worst, and the parallel MOV doesn't even see them.
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The rules are VERY different here, and most likely in most 230V countries except New Zealand, where you don't need to be a licensed electrician. We can't even legally replace power points or faulty light switches. (although I have done so.) It has to be done by a licensed electrician.

230V AC is far less forgiving than 120 V AC !!! It's not much fun being thrown across a room and being unable to answer a worried child for almost a minute to tell them you are O.K.

 

You also need to remember that the original poster is from a 230V 50Hz country where similar rules are likely to apply due to safety reasons.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Proper surge protection places an MOV in parallel with the mains, then one from each leg to ground. Common-mode surges are some of the worst, and the parallel MOV doesn't even see them.

 

The key words in your reply are Proper surge protection.

Basic protective power boards often only use a single MOV /Varistor, although the more expensive types with claimable insurance in the event of a failure to protect, would also use 3 MOV/Varistors. My own heavy duty DIY filter does however use all 3 as described. In Au. the Neutral is also connected to Earth at the Power board. Originally in Au, the earth was typically bonded to a water pipe, however, these days water pipes may no longer be made of metal.

Yes, I discovered that problem many years ago at a rented house which was very prone to electrical interference. The bonded connection had corroded.

Alex

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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The rules are VERY different here, and most likely in most 230V countries except New Zealand, where you don't need to be a licensed electrician. We can't even legally replace power points or faulty light switches. (although I have done so.) It has to be done by a licensed electrician.

230V AC is far less forgiving than 120 V AC !!! It's not much fun being thrown across a room and being unable to answer a worried child for almost a minute to tell them you are O.K.

 

You also need to remember that the original poster is from a 230V 50Hz country where similar rules are likely to apply due to safety reasons.

Yes, I'm unfamiliar with the rules in other countries. However, it doesn't change there surge protection needs to be to be effective. So, in Au they don't permit "whole-house" surge protection at all?

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The key words in your reply are Proper surge protection.

Basic protective power boards often only use a single MOV /Varistor, although the more expensive types with claimable insurance in the event of a failure to protect, would also use 3 MOV/Varistors. My own heavy duty DIY filter does however use all 3 as described. In Au. the Neutral is also connected to Earth at the Power board. Originally in Au, the earth was typically bonded to a water pipe, however, these days water pipes may no longer be made of metal.

Yes, I discovered that problem many years ago at a rented house which was very prone to electrical interference. The bonded connection had corroded.

Alex

 

Surges come from two general sources: inside the home and outside. Inside-generated surges (according to some surge-protector manufacturers at least) comprise most of the surges, like 90%. But they are generally short, relatively small in amplitude, and, they are nearly all differential, and are best dealt with by local protection at the equipment. Surges from the outside, unless you're in an industrial area, are largely common-mode, and lightning related. Those things are huge, and destructive, and need to be taken to ground at the point of entry to the building. Since the big concern in the surge-protection world is equipment destruction by a huge surge, the protection devices we need must deal with differential and common-mode, and depend on having a good ground to work with. Yes, that lets out the cheapie power strips you by at hardware stores. However, "insured" protectors are no guarantee either. Just ask anyone who's ever tried to make claim for damaged equipment. They have ways to wriggle out of those claims, and the guarantee is largely fictional. The other problem is having a good path to ground/earth at the equipment, which is usually not the case, and why people still have their gear destroyed with a surge protector in place.

 

We should probably also mention, as you have implied already, that protection devices come in two flavors too: the self-sacrificing MOV kind, and the low-pass filter. Since a surge is mostly a high-speed transient, they can also be filtered off, which is also very effective, though quite expensive. Filter type protectors also usually include the 3 MOVs.

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So, in Au they don't permit "whole-house" surge protection at all?

 

Not that it means much, but I have never seen it mentioned here as regards to domestic installations, and if it was permitted

with domestic installations, it would certainly need to be installed by a qualified electrician.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Surges come from two general sources: inside the home and outside. Inside-generated surges (according to some surge-protector manufacturers at least) comprise most of the surges, like 90%. But they are generally short, relatively small in amplitude, and, they are nearly all differential, and are best dealt with by local protection at the equipment. Surges from the outside, unless you're in an industrial area, are largely common-mode, and lightning related. Those things are huge, and destructive, and need to be taken to ground at the point of entry to the building. Since the big concern in the surge-protection world is equipment destruction by a huge surge, the protection devices we need must deal with differential and common-mode, and depend on having a good ground to work with. Yes, that lets out the cheapie power strips you by at hardware stores. However, "insured" protectors are no guarantee either. Just ask anyone who's ever tried to make claim for damaged equipment. They have ways to wriggle out of those claims, and the guarantee is largely fictional. The other problem is having a good path to ground/earth at the equipment, which is usually not the case, and why people still have their gear destroyed with a surge protector in place.

 

We should probably also mention, as you have implied already, that protection devices come in two flavors too: the self-sacrificing MOV kind, and the low-pass filter. Since a surge is mostly a high-speed transient, they can also be filtered off, which is also very effective, though quite expensive. Filter type protectors also usually include the 3 MOVs.

 

The only damage that I have had has been due to external causes .One was due to a lighting strike across the road at a municipal swimming pool, which damaged some of my electronic gear, and damaged a stove circuit, as well as vaporising a complete section of underground telephone cable, although the telephone survived..

The other was due to work on a new electricity substation up the road when construction caused a large voltage surge for several seconds which destroyed a couple of transformers in an amplifier which was in use at the time. There was a flashover to the core of the larger toroidal transformer. I had only just moved into the premises and my filter with the 3 VDRs hadn't been put in line at that stage.

 

Alex

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Not that it means much, but I have never seen it mentioned here as regards to domestic installations, and if it was permitted

with domestic installations, it would certainly need to be installed by a qualified electrician.

 

You are taking about Australia right and not other countries ? as we have this capability the USA. The local power company if they offer the service does the install of a surge device before the meter after doing a through measure of the ground but of course there is NO 100% guarantee that mother nature will not fry your home and the components inside. I reside in the lightning capital of the US and nothing is safe but I at least know that I did what I could afford.

The Truth Is Out There

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Incidentally, FWIW, it isn't easy to get a low resistance earth just by using a couple of earth stakes.

When with Telstra I had to measure the earths of local PABX s (Private Automatic Branch Exchanges) etc. from the local Telephone Exchange before they could be commissioned. It wasn't always easy for the outside tech/linesman to get below the maximum of 30 ohms.

I suspect that at least one of the local linesman "watered" the stakes after a liquid lunch !

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Incidentally, FWIW, it isn't easy to get a low resistance earth just by using a couple of earth stakes.

When with Telstra I had to measure the earths of local PABX s (Private Automatic Branch Exchanges) etc. from the local Telephone Exchange before they could be commissioned. It wasn't always easy for the outside tech/linesman to get below the maximum of 30 ohms.

I suspect that at least one of the local linesman "watered" the stakes after a liquid lunch !

 

In the US we are required a max of 25 ohms or less and that is for a single-made electrode. National Electrical Code requirement in Sec. 250-54. But just because you meg the ground is within spec it doesn't mean you will have a "good round". However, you can trace most problems to poor quality connections on the equipment-grounding system. But I think more attention needs to be placed on the impedance of the equipment-grounding system and the verification of low-resistance bonding connections between grounding planes after the ground have been checked.

The Truth Is Out There

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mav52

On one occasion I even found that the earthing at French's Forest T.E. in Sydney had deteriorated. and it had to be rectified.

The Telephone Exchanges had special large earth grids at the time of construction. The new replacement T.E. at the major shopping centre of Chatswood in Sydney had special problems with earthing as it was located next to, and parallel to Chatswood Railway Station.

Much depends on the type of terrain at the location itself, and I wonder how many earths are still meeting their original requirements? For domestic situations the old method of the earth bonded to the water supply pipe had clear advantages in obtaining a low resistance earth at the time. If a section of water pipe had to be replaced at a later date with plastic pipe, the earth may no longer be adequate ? .

 

Alex

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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mav52

On one occasion I even found that the earthing at French's Forest T.E. in Sydney had deteriorated. and it had to be rectified.

The Telephone Exchanges had special large earth grids at the time of construction. The new replacement T.E. at the major shopping centre of Chatswood in Sydney had special problems with earthing as it was located next to, and parallel to Chatswood Railway Station.

Much depends on the type of terrain at the location itself, and I wonder how many earths are still meeting their original requirements? For domestic situations the old method of the earth bonded to the water supply pipe had clear advantages in obtaining a low resistance earth at the time. If a section of water pipe had to be replaced at a later date with plastic pipe, the earth may no longer be adequate ? .

 

Alex

 

Speaking of ground boning at a home, having worked for a local phone company in Fla before my tour of 30 year duty with ATT/Bell labs and Lucent I could tell you a story about a customer complaining about her dog howling every time the phone rang.

The Truth Is Out There

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The dog wasn't by any chance chained up to a water pipe at the time ?

I seem to vaguely remember a story like that. I also remember a story years ago about a major U.S. city where there was great difficulty making calls from one side of the city to the other due to the shocking state of the network, where each level of managers had been fudging the figures passed on the next management level.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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The dog wasn't by any chance chained up to a water pipe at the time ?

I seem to vaguely remember a story like that. I also remember a story years ago about a major U.S. city where there was great difficulty making calls from one side of the city to the other due to the shocking state of the network, where each level of managers had been fudging the figures passed on the next management level.

 

Oh yes the dog was chained to the outside faucet which dripped

The Truth Is Out There

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Much depends on the type of terrain at the location itself, and I wonder how many earths are still meeting their original requirements?

Probably not many hit their original performance, some may still be adequate, quite a few probably not. It's not so much the terrain as ground conductivity.

For domestic situations the old method of the earth bonded to the water supply pipe had clear advantages in obtaining a low resistance earth at the time. If a section of water pipe had to be replaced at a later date with plastic pipe, the earth may no longer be adequate ?

With the plastic, depending on where it is in relation to the ground connection, you might not have a ground at all, but then, even old metallic water pipe may no longer provide an acceptable ground.
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dc2bluelight

I was just generalising with the use of the word terrain.

French's Forrest for example was notorious for poor ground conductivity, as well as being quite rocky.

Low level earth hum over certain routes (analogue)from Frenchs Forrest to other exchanges wasn't unknown either.

With the plastic, depending on where it is in relation to the ground connection, you might not have a ground at all, but then, even old metallic water pipe may no longer provide an acceptable ground.

Unfortunately,we put a lot of trust in these earths that rarely get retested over the years.

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Thank you very much for all of you guys for great explanation. It seems that there is no common rule here and the power quality is rather disputable if audible and at what level. I will try to remove that additional SPDIF connection and check the result of course.

 

Regarding my DAC, so far I am pleased with its sound, but I would really want to try USB/SPDIF converter if somehow I find the place where I can borrow it and check at home.

--

Krzysztof Maj

http://mkrzych.wordpress.com/

"Music is the highest form of art. It is also the most noble. It is human emotion, captured, crystallised, encased… and then passed on to others." - By Ken Ishiwata

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