[673] Simple Kill Switch

Date: May 27th, 2010 | Comments : [16] | Categories: DIY.

Kill switch

This is a simple passive kill switch that can be constructed in a tiny box like the 1590A or even smaller. The circuit is symmetrical so either jack can be the input or output. The resistors were added to make sure that the output of the circuit driving the switch was not shorted to ground, which might cause a problem with some designs. Use a normally-open momentary switch.

Kill switch 2

A 5k potentiometer can be added so that the amount of signal reduction can be adjusted. In the first version, the signal will be cut completely off when the switch is closed but the version with the pot can be adjusted so that some signal still passes through when the switch is hit.

If the circuit pops with your pedal, put a 2.2M resistor across the switch terminals (from one switch lug to the other).

The circuit is non-critical but a shielded box is still recommended.


16 Responses to “Simple Kill Switch”

[1988] Bigredlevy Says: 5:41 pm, December 28th, 2010

why are there two resistors in series with the jacks? Wouldn’t it be better to place one resistor between the switch and earth, so as not to degrade the signal?

[1998] admin Says: 2:11 am, January 2nd, 2011

A resistor between the signal, switch and ground will limit the amount of reduction that is possible. Doing it the way that is shown in the first drawing will allow complete signal cut off.

[2018] BKW Says: 1:06 am, January 8th, 2011

Is there a way to put a Red/Green LED in place to show when the signal is on (green) or when the signal is muted (red)?

[2082] Steve Says: 10:29 pm, February 24th, 2011

If you wanted to use an LED it wouldn’t be a passive circuit anymore, you’d need to include some power source.

[2172] Ernest Says: 7:36 pm, April 18th, 2011

is this true bypass? I’m a little bit new at this sorry.

[2173] Ernest Says: 8:34 pm, April 18th, 2011

I also wondered how I could wire an LED into the equation..

[2194] martin Says: 4:51 am, April 30th, 2011

i would replace the resistors with large capacitors(1 microfarrad or larger) to prevent ac shortcicuit,that won’t deteriorate your signal and for the led you would need a double make switch so you can kill your guitar signal(shorting it to the ground) and with the other switch you would make a separate circuit including a led a resistor a battery and that second swith in series,the value of the resistor depends from the type of led and the voltage of the battery,a double make switch you could make youself easily and cheaply by combining 2 seperate ones or just designing and making it yourself

[2226] Jones Says: 1:56 am, June 29th, 2011

anyone got any pictures of finished wiring for the second diagram, this is my first pedal and im lost

[2239] Lucas Says: 9:52 pm, July 6th, 2011

Where do I put the negative wires?

[2246] admin Says: 1:34 pm, July 7th, 2011

All of the ground points connect together.

[2257] Lucas Says: 11:12 am, July 8th, 2011

Ugh I still couldn’t get anything to work…

[2478] zespha Says: 1:51 am, December 5th, 2011

will you show unto us how to do that together with the LED indicator of the signal under effects?

[2723] Patrick Says: 1:16 pm, March 28th, 2012

Would it be acceptable to use a DPDT switch to create a true bypass pedal so that one route goes Input-Switch-Output and the other Input-Switch-470R-Pot-470R-Switch-Ouput?

[3769] Jay Says: 11:38 am, February 15th, 2013

I’m new to all of this still but I’m looking to make a bit of a weird killswitch. Is there anyway I could make it where it could be both normally open and normally closed momentary via a latching switch? I swore I saw something online that used a latching switch to change how the momentary switch works, but I haven’t been able to find it since. That or could I use a latching switch to change from a circuit that has a normally open momentary to a different circuit that has a normal closed?

I also plan on making two killswitches like this (one with two inputs and outputs, and one with just one each). Any help is appreciated.

[751328] Aisha Says: 10:45 am, October 21st, 2015

What a simple, elegant explanation. Thanks!

I’m still getting a little pop when I hit the switch. Would raising the value of the resistors help without affecting my signal path?

[751724] admin Says: 8:41 am, October 22nd, 2015

To lower the pop, try putting a 10M resistor across the switch terminals, i.e. from one switch lug to the other.

regards, Jack


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