Hello!
This basically has to do with finding the grounding scheme that will result in the quietest operation of your system. The ground select switch we use now has 2 positions - 'hard ground' and 'floating ground'. I used to have a third switch position on the TX102 pre-amps (that came from Thorsten's info) that grounded the inputs through resistors. I called it a 'soft ground'. The positions were:
Float: Input grounds isolated from the output grounds
Soft ground: Input gounds connected via a resistor
Hard Ground: Input grounds connected via a wire
The soft ground was the source of much confusion and discussion and in the end it seemed systems either wanted to float or to be hard grounded so about a year back I eliminated the 'soft ground'. There is nothing wrong with it at all - it's just that when the soft ground worked well hard ground also worked just as well.
Many Thanks!
John Chapman
www.bentaudio.com
