"Grunge"

[Mark (Basspig) Weiss]

As this thread has just crossed over from rational discussion into the occult mystical realm, I've nothing further to contribute here and will have to duck out to keep from laughing myself to death.

 

[MylesBAstor]

As this thread has just crossed over from rational discussion into the occult mystical realm, I've nothing further to contribute here and will have to duck out to keep from laughing myself to death.

Me too.

 

[mep]

I am still hoping that someone will post a good grounding scheme that would make sense to use in any system. I am not plagued with EMI/RFI issues in my house. My listening room is a part of the addition that I had built on to my house so I could have my own space. My room is underground and is dead drop quiet. I had a separate 100 amp service box wired in just for the addition and the electrician did the cleanest wiring job I have ever seen on a panel. Since the 100 amp breaker box is in a closet located in my listening room, I would not be able to tolerate a balanced transformer if it made noises like Doc B. was describing. My room is so quiet that you could literally hear a pin drop and I want it to stay that way. I find it interesting that some people are still discovering that you can't have dimmer switches around audio gear.

I think a good grounding scheme could benefit everyone if properly designed and executed. Thankfully I am not dealing with the demons that are plaguing some people here. I wouldn't buy a house that was next to a radio/tv transmitter. If things are so bad that you have to turn your house into a giant faraday cage that is just a bit much. I work around RF all day every day in my job, but at least it is terminated into dummy loads and not being transmitted. I wouldn't be happy knowing everytime I was standing in my yard I was having my onions roasted by a 50Kw transmitter beaming right at me.

 

[Mike Lavigne]

Mark,

regarding potential transformer noise that Doc was speaking about; the 10kva 'Q' Transformer in the Equitech panel i have does emit the very slightest hum, and i mean faint 'hummmm' when you get up near it (within 4-6 feet) in the hallway outside my room when everything is quiet. it's about 50% as loud now as when it was first installed 2+ weeks ago.....so it may end up being absolutely dead quiet. if it was louder i could line the door to the cabinet with thin insulation, but that is not necessary. one other thing is that the cabinet has 2 powered vents which are triggered by temperature switches. they have yet to come on. the cover plate over the transformer is very slightly warm to the touch.

here is an excerpt from the Equi=tech FAQ regarding acoustic noise from a transformer. i'm no EE and cannot say how much of this answer is science and how much is hype. but i can say that the damn thing is very very quiet for 190 pounds of working OFC copper.

1. Acoustical noise. Most of the time, standard toroid transformers will perform quietly and emit almost no audible noise. However, in residences and in other areas with poor utility power, the transformers react physically to excessive current distortion. The more distortion, the more the transformer vibrates. This dissipation of reactive energy, while being very helpful to equipment power supplies, can still be quite annoying. It is interesting to note that this problem has been worsening since the mid-90s. Our customer support technicians report acoustical noise problems in as many as 2 out of 5 residential locations whereas in the early 90s, the frequency of reported noise problems was perhaps 2 out of 50 locations. This recent decline in power quality is due to the increased use of microwave ovens, personal computers, HDTVs with large switching power supplies, home security systems, lighting controllers and other types of home theater equipment, especially digital audio and video components. All of these types of loads produce excessive current distortion which distorts the power in an entire neighborhood. The problem continues to worsen. Commercial users, though somewhat protected are not immune to this problem either. Most states have minimum power quality standards and tarrifs for commercial occupancies which may alleviate the problem at times, but none at all for residential neighborhoods. “Q” transformers are immune to current distortion and operate much more quietly than any other type transformer.

i live in a neighborhood of 3-6 acre lots, and i have my own transformer out at the street. so my power is already reasonably quiet. maybe in a dense urban or industrial environement the transformer noise would be worse.

btw, i do have some documentation on grounding from Equitech, which i would be happy to e-mail to you. it's a bit confusing to me but it may be helpful to you.