Tweaks
May be you saw before but I could not found in art of sound forum, it shall be in your interest, two different tweaks recently catched my and my local DIY guys attention.
After making two and some listening tests aggreed that both works.
1) broskies ground isolator between plug ground and chassis ground.
2) Battery Ground Tweak
Both of them are very simple things
1) 10 ohm resistor+0,01-0,1 uF capacitor + bridge rectifier in paralel
Plus side of the bridge rectifier will be on the power socket Side.
Here is the logic
New House-GND Kit
The wall outlet's third jack connects to the house ground, which is also known as "earth," as the house ground is often created by attaching the wall socket's neutral connection to an 8-foot metal rod buried in the dirt under your house or to the cold-water pipe, assuming that the pipe is made of metal. Many old houses and apartment buildings do not offer a connection to the house ground, only the two power wires, which is unfortunate, as the a connection to the house ground is a safety feature.
For example, say that something goes terribly wrong in your power amplifier and the B+ attaches to the chassis. Well, if the chassis does not make a connection to the house ground, you could receive a lethal shock from touching the energized chassis. But with a solid connection made to the house ground, the B+ voltage would drain away safely.
The big problem for us audiophiles is that house ground often becomes contaminated by other electrical devices in your house. This could be avoided, if when they laid out the house wiring, each wall socket got its own separate house-ground wire that in a star-grounding fashion traveled independently back to the houses fuse box and its ground connection. But as this excellent setup would require much more wire, it is seldom performed; instead, most house-ground connections daisy chain their way back to the electrical panel's house ground, much like Christmas-tree lights strung in series. Some electrical equipment is miswired internally, so the neutral and house-ground connections are reversed. This causes something which should never occur: the house-ground wire seeing a sustained current flow.
(Ham-radio operators face much more dangerous situations, as lightning can hit the transmitting antenna and then travel through the house wiring until it hits the house ground, setting your house ablaze along the way.)
How do you know if you have a dirty house ground connection? Simply attach an AC volt meter to the neutral and house ground connections on the wall socket and read the voltage. It should read 0V. In my listening room, it doesn't, as there is a 500mV AC voltage difference between the two. Is that a problem? Not if you plug a lamp or a toaster into the wall socket, but it is if you plug in some audio equipment, as the resulting hum testifies loudly.
The workaround is to use* the following circuit.
The diode bridge only connects the two grounds when the voltage difference between them exceeds about +/-1.4V. The capacitor allows high-frequency noise to find a path to the house ground. The 10-ohm power resistor makes a DC connection between grounds, while still offering some isolation between grounds.
2) Battery ground Tweak ( BGT ) is also simple
9v Battery with min 22000 uF electrolytic cap and min 0,1 uF by-pass cap in parallel
1 wire to solder on (-) pole
And connect it to any empty (-) rca input of CD, dac, pre etc.
It works with speaker as well ground line input
Changing the electrolytic cap and especially by-pass cap changes sound
9 v is ideal above 9 v makes upper frequencies too front,
Original idea came from Bud Purvine diyaudio forum. But upgraded by some others
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Originally Posted by tiguan
