A star ground is a pattern of 3 or more grounding rods all connected together and connected to the earth ground terminal in a power distribution box. This is usually a more effective ground compared to a single point ground which is common in housing in the US. You should be able to find plenty of information on grounding methods on the net or check out the book "Grounds for Grounding" or find out what the traditional phone companies used in your area.
Unless you have dedicated wiring for your stereo it has short comings, ground loops are just one of the possible issues. Voltage drop is probably a more common issue, wiring is probably to small creating a weak link in the performance.