Rotary switch LEDs for channel selection

[stree]

Firebottle, thanks for pointing that out. Intended to use green LEDs, do you know typical voltage for these?
The intended layout will be, TT to pre-amp, to switch, to amp for one channel. R Pi with DAC, to switch, to amp on other channel.......Probably easier to pick up low voltage from Pi, I am guessing?

[Firebottle]

Voltage for green LED is about 2.1V. Yes pick up the 5V from the Pi, try a resistor value of 1.5K or 2.2K ohm.

If too bright then increase the value of the resistor and vice versa.

[stree]

Great, thanks Firebottle, much appreciated.