big mans aby box revisited

[edad]

on big mans layout pic are the 3 l.e.ds grounded to gether with or without a resistor. or grounded seperately With or without a resistor?? If necessary what is the resistor values?.Will this work at stage volumes without pops?  thanks

[TheBigMan]

If you are using a battery then everything, signal and power grounds, are tied together.  On my own AB I use an adapter, so the power and signal are kept seperate and there is no risk of popping from the LEDs at all.  There needs to be a resistor somewhere in the circuit with the LED, but as it's a current limiting resistor it can be between the LED and ground or between the LED and +9V depending on what's more convenient.  1K will be fine for most standard LEDs, for hi-brightness types you'll want something larger, maybe as much as 10K for some LEDs.

I would NOT recommend using this type of ABY for amp switching however.  I would always recommend using one with proper isolation for that purpose, to eliminate any possibility of ground noise.