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Grounding in guitar amps, Safety issue

11/30/2000 6:50 PM
Dominik	Grounding in guitar amps, Safety issue Hi there, just a quick question: In some old german tube schematics of studio tube equipment I saw the following: Star-grounding, with all local stage grounds going to ground on the first filter cap of the power supply. This "ground" is then connceted (and only here) to chassis ground (which is connected to the wall outlet ground (earth)) through a 100 Ohm resistor. The ground of the input goes directly to the filter cap ground. Is there a danger in using this setup in a guitar amp?? Could there be a different potential between the circuit and the chassis ground. So there could be the danger of electrocution when something goes wrong (short between B+ to circuit ground). Or would most of the current flow through the 100 Ohm resistor?? Thanks for any insight on this, Dominik

11/30/2000 6:50 PM

Dominik

Grounding in guitar amps, Safety issue

Hi there,

just a quick question:

In some old german tube schematics of studio tube equipment I saw the following:

Star-grounding, with all local stage grounds going to ground on the first filter cap of the power supply. This "ground" is then connceted (and only here) to chassis ground (which is connected to the wall outlet ground (earth)) through a 100 Ohm resistor. The ground of the input goes directly to the filter cap ground.

Is there a danger in using this setup in a guitar amp?? Could there be a different potential between the circuit and the chassis ground. So there could be the danger of electrocution when something goes wrong (short between B+ to circuit ground). Or would most of the current flow through the 100 Ohm resistor??

Thanks for any insight on this,

Dominik

Replies:

Stephen Conner [QUOTE]Is there a danger in using t... -- 12/6/2000 2:22 PM