Golly, what a concept. Lower the hum and the sound improves. What will they think up next? Nice research man!

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Ethan, have you ever tried lifting the grounds? Do you use star grounding, or another system?

I have all of my audio gear plugged into the same wall outlet, through a power strip of course. My studio setup is all balanced ins and outs, so I don't have any hum or noise or radio station problems. My living room system is not balanced, but I don't have any hum or noise there either. Even putting my ear to the speakers I don't hear any noise.

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Star grounding did more than reduce hum, things didn't hum to begin with. Lower noise floor.

How did you determine the noise was lower? By listening with your ear right at one speaker both ways? A good system should never have audible noise at normal listening levels at the listening position.

--Ethan

I had to lift the ground on my pre-amp because I was experiencing a ground loop. What's a star grounding scheme? What could you do aside from lifting the ground if you're experiencing a ground loop?

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I've also heard it can be a bit dangerous to lift all the grounds. Any tales?

Those that may have had tales probably did not survive to tell them. If they did, they are just damn lucky!

Risking one's life is one thing. Risking the lives of family is another. This is _very_ dangerous and is no cure for noise in a system.

I can't believe PS Audio sells those removable ground pin power cables!

Bite the bullet. Pay an electrician to properly ground everything, cable, satelite dish, antenna, service panels, ect. to the same location. It sounds just fine!

RG

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Bite the bullet. Pay an electrician to properly ground everything, cable, satelite dish, antenna, service panels, ect. to the same location. It sounds just fine!

That comes from someone living in "Tornado Alley". Take his advice just this once. Bury the post deep in the ground.

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What's a star grounding scheme?

All of the ground wires from different places come together at a single central location. So a diagram looks sort of like a star with the central point in the middle.

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What could you do aside from lifting the ground if you're experiencing a ground loop?

Good question! Grounding is one of the few aspects of science that has a black art component.

--Ethan

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What could you do aside from lifting the ground if you're experiencing a ground loop?

Place "solving ground loops" in a search engine. The first thing to try is reversing the orientation of any non-polarized AC plugs and using an outlet tester to make certain all of the AC outlets are properly wired.

With US domestic electrical standards the neutral is tied to ground (http://hyperphysics.phy-astr.gsu.edu/hbase/electric/hsehld.html), unless you are using an outlet that has an isolated ground such as a hospital grade outlet, or you are using balanced electricity. So in many circumstances "lifting" ground isn't dangerous. People just need to do their homework before proceeding.

I've known of a number of people that lift all of the component grounds except one. Before trying that make sure that component is grounded through the center pin by opening the component or checking with the manufacturer. A IEC plug on the back is no guarantee that the component has a separate ground. I am aware of a small number of manufacturers that use IEC outlets to allow upgrading of power cords but only connect the hot and neutral because they feel that their components sound best with ground lifted. As long as one component is properly grounded everything in the system is grounded through the interconnects. However if someone were to start disconnecting things in the system in the wrong order WHILE there was a fault on the line they would be in danger. If someone were to try this they should always think through component swaps and system disassembly very, very carefully.

With a completely remote controlled system a user could avoid every touching the system and "lift" all grounds but I would never recommend it. Even I'm not that adventurous.

* The above post is meant as hypothetical only and as a beginning point for further research. DO NOT proceed ONLY armed with my information. Do your own research and if you don't understand it or aren't comfortable either ignore the topic completely or call an electrician.

On slightly different note ----
When I took delivery of my Boulder integrated I was puzzled by a warning printed on the rear of the amp itself, and in the manual. "DO NOT CONNECT ANY OUTPUT TO GROUND". At first this made no sense to me so I asked Boulder why they'd felt the need to place that warning. Apparently it's not just the danger of some idiot connecting the amps output to mains ground but also the earthing arrangements on some electrostatic speakers could cause an amp of Boulder's type to self immolate. So, I had my tech mate speak to the nice people at Soundlab . They recommended an alteration to the stats earthing arrangements. I never did understand any of this or how it was implemented. It just goes to show though, there are more risks than simply killing yourself when it comes to earthing arrangements.
As to 'floating earths' and as I'm ignorant of most electronic basics, I would never detach any components earthing connection without having a tech guru to advise me . Over the years I've noticed a number of posts of forums & news groups advising this as just another tweek. Floater beware! ! ! !

Nope- Ground lifting, esp. now that I gots a class-A amp sounds like a widow making endeavor. I got a dedicated power line which goes through a good power conditioner and upgraded cords- each made a big difference and all are safe.

the part of the house where my listening room is is very old. although i upgraded the outlets to hospital grade, i don't believe they were actually grounded. hum was never a major problem, but it existed at high levels.
about 2 weeks ago, an electrician friend ran a dedicated line to the breaker box and wired in all 3 wires. i noticed things instantly quieter, no hum and very odd, the phono cartridge seemed to ride the groove quieter. old records that had seemed noisy were much quieter. don't know why, but i'll take it.
i don't know how this relates to ground lifting or star grounding, but thought i'd pass it along.