james4

Well, the old killswitch thread has been out of commission for a little while now, so here goes the new one..

Remember, this thread is going to be a work in progress. What I've put together here is by no means a 'complete guide', but I hope it's enough to get most people through installing a killswitch.

If you have anything to add, whether it's pictures, comments, links, or anything that could be useful, don't hesitate to put them up, and I'll add them into the thread

Same goes for any questions anyone has. if you still don't get something, just ask, and there's lots of knowledgeable people around who can help you out.


For questions about guitar wiring not specific to killswitches, please direct them to the Wiring Thread
Theres also some helpful links in that thread, if you need help on soldering

For even more resources, head over to the GB&C Central Hub



Heres a basic outline of the first few posts:

1. I don't know anything ..why am I here, and where do I start?
2. How will it work?
3. What switch should I use?
4. Where can I get those switches?
5. Diagrams and wiring it all up
6. Pictures/ Videos/ other useful material


1."What's a killswitch, and where do I start?"




here's the output jack of a guitar (some may have sheilded wire, or more than one wire connected to ground, but this is just for reference).


most jacks will have 2 solder tabs on them. one is the tip, and the other the sleeve. This corresponds with the 2 sections of your patch cable


There's a whole lot to learn about how a signal is carried and how voltage works, but for this application, all we need to know is that:
-the sleeve is grounded
-the tip is where we connect our hot output. it's basically the one that carries the signal from the pickups.

..so let's look at the basic function of a killswitch. our goal is that when the switch is pressed/flicked/engaged/whatever, the output of your instrument is cut, making the guitar silent, as if the volume is suddenly dropped to zero.

Seems easy enough. All we need to do is stop any signal from getting to the the hot output (the tip of the jack) when the switch is engaged.

let's start looking at how we can do that:

__________________
Wiring your guitar?

james4

2."How will it work?" Alright, so we now have a goal. We want the signal to remain as-is when the switch isn't being activated. When the switch is engaged, no signal whatsoever is to get to the tip of the jack/ hot output.

So how are we going to do that? There's 2 simple ways.
one way, and what would seem like the most obvious way, is to break the connection between the guitar's output and the jack using a switch.
basically, we want this to happen when we press the switch:

In a perfect world, this would work just fine. we're stopping the signal from the pickups from getting to the hot output, and we'd hear nothing when the switch is engaged.
Unfortunately, we don't live in a perfect world. Just because we stop the pickup's signal from getting to the hot output, doesn't mean we're stopping all signals from getting there.
Computers, phones, TVs, the wiring in your house, microwaves, and pretty much anything electrical you can think of, all give off EMI (electromagnetic interference) / RF interference (radio frequency interference). an extreme example can be heard when you play guitar in front of your computer, or if you get a phone call while your cell phone is on top of your amp.

If you wire a killswitch to simply disconnect the guitar's output from the jack, you're still leaving the tip of the jack wide open to receive static and hum caused by interfering signals.
If you turn on your amp, plug a patch cord into it, and leave the other end of the cable unplugged, you'll hear the same amount of hiss and noise.

note that in some areas, this may not seem like a big deal. your basement might be relatively quiet in terms of RFI, but playing in different rooms of your house could give you different results. You definitely don't want to use this kind of killswitch if you're on a stage underneath a bunch of bar lights and fluorescent neon beer signs..

So now we know that cutting off the output from the guitar doesn't actually mean we're left with a completely silent output. so what do we do?
remember how the sleeve of the jack is grounded? well, if we connect the hot output to ground, theres no way a signal can be present

So now, when we press the switch, we want this to happen:

connecting 2 points electrically is essentially making them the same point, and a voltage (signal) is apparent only when there's a potential difference between 2 points. the signal used to be between the tip and sleeve of the jack, but if they're the same point (both grounded), there can be no signal. not from the pickups; not from anywhere.

The only issue some people may have with this wiring scheme, is that there's sometimes a 'pop' noise when you switch from the normal signal, to 'killed' position. the solution for that is a very high value (very high resistance) resistor across the terminals of the switch. We'll go into greater detail on that in the wiring section.

What's important now is that we have an idea of what we want to happen when the switch is activated. We want to short the output to ground.

__________________
Wiring your guitar?

james4

3."What switch should I use?"
Now let's look at the different types of switches: The most commonly used switch styles are toggles, and momentary push buttons. within these 2 categories, there's a few different options.

Lets start with toggles.
Based on the fact that you're reading this thread, I'm going on the assumption that you probably haven't done much guitar modding before, and your only parts resource may be Radio Shack (or similar places, for those in different parts of the world).

at radio shack, you'll probably find 3 kinds of switch:

SPST (single pole, single throw)


SPDT (single pole, double throw)


DPDT (double pole, double throw)


You're able to find any of these variations in latching, as well as momentary style. Your choice of locking/ momentary is based on how you want your switch to work. if you want to flick the switch to the off position, and have it 'bounce' right back to the 'on' position, you want momentary. If you want to be able to flick the switch to 'off', and leave it there without holding it in place, go for latching.
SPST, SPDT, and DPDT will all work, but you only need a SPST for normal operation.

Here's an explanation of all these crazy poles and throws:

You may notice that the diagram also lists a DPDT on/on/on switch. that's a 3-position switch, and it can be wired a few different ways
[on] / [kill] / [on]
[kill] / [on] / [kill]
[kill] / [on] / [on]

or whatever.. wiring's not much harder, but just ignore it if it's not what you want. There's not much of a point in having a switch like this, since you don't really need more than one 'on', and more than one 'kill' position

wiring for it can be found in the wiring section, as well.

So that's toggle switches for you. you may also want a rocker switch, or slide switch. either of those 2 will have the same options and operation as a toggle. the only difference is just the housing of the switch, really.
The lugs on a rocker or slide switch will be the same as on a toggle switch, so the wiring will be identical


On to buttons! some push buttons have the same pole/throw layout as toggles, so just refer to the appropriate diagram and explanation for them.
a typical momentary push button just has 2 lugs


you can get 2 kinds of momentary buttons:
Normally closed (also labeled as 'NC', or 'push to break')
and normally open (also labeled 'NO'; 'push to make')
if you want to ground the hot output (as explained in the above section), you need to use a normally open/ push to make switch. Keep this in mind when you're choosing the switch to buy

__________________
Wiring your guitar?

james4

4."Where can I get those switches?"

Locally, a store like Radio Shack (in the US), the Source (Canadian version of radio shack), or Maplin (iirc, this is a big store in the UK?) will have the kind of switch you need.
If you're looking for something more specific, try these places:

www.mouser.com
www.smallbearelec.com (They mostly sell parts for pedal building, but have an alright selection of switches, as well)
www.partsexpress.com


*more links to be added as the thread develops*


Those are a couple of general links, but here are some switches that are quite popular (again, more to be added as people contribute):

thanks to SYK for these few:



and here's a picture of some more arcade style switches that Wilki posted in the old killswitch thread
according to the url, they're from www.txpinball.com. they don't have much for sale that'll be useful, but they look pretty damn cool, so I put them in anyway

__________________
Wiring your guitar?

james4

5."Diagrams and wiring it all up"

So..now we should know what we want the switch to do, and have the switch to do it.

This diagram will work for any guitar with a master volume and SPST switch.
One terminal is connected to the volume pot's casing. that's a ground point. The other side is connected to the middle lug of the volume pot. That lug of the volume pot is connected to the tip of the output jack, and is the hot output of the guitar.
So when the switch is activated, and the lugs of the switch are connected, the signal is killed


if you have a DPDT switch and a master volume, the wiring is the same as above, except you'll have an extra lug to the left or right of the 2 used lugs



If you have a Les Paul style guitar (with separate volume controls for each pickup), you can use this diagram:


Depending on the kind of guitar you have and where you want to put the killswitch, wiring the killswitch to the pickup selector may not be very convenient. Instead of connecting one end of the switch to the hot output at the pickup selector, you can also connect it to the tip of the jack.
Same goes for the other side of the switch's connection to ground. It doesn't have to be to the ground point on the selector. it can be to any ground point

Here's part of a diagram Will_Minus made. same as the other 2 diagrams, just drawn a little different


This picture is from XibanezedgeX. this is for a strat style guitar, or any guitar with a master volume



[update 16/03/10]
Earlier, I mentioned putting a high value resistor between the lugs of the switch, if you have problems with popping when using the switch.

First of all, get your hands on a very high resistance resistor. Usually, you can find a 2M2 (2.2Meg, or 2200000 ohms) resistor fairly easily, at almost anywhere that sells electronic components.
in a little while, I (or anyone else, if you want to volunteer) can play around with different resistor values to see how low (resistance-wise) you can go, but ..if the value you use is too low, you'll experience some treble and volume loss, which is never nice.

Anyway, all you need to do is put the resistor between the two lugs of the switch you used.
It should be pretty straight forward, but heres a diagram if you really don't know what I'm talking about:


If space is an issue, you can put the resistor between the lugs of the output jack, instead of the switch.
It'll have the exact same effect, it's just another option you have..


Hopefully that's enough of an explanation to get it all together for you, but feel free to post if you have any further questions.

Again, if you put a killswitch in your guitar, please feel free to post pictures, comments, links to where you bought some crazy switch, or anything else that could help others out.

The last post will be made up of pictures, videos, or anything else that should be mentioned

__________________
Wiring your guitar?

james4

6. "Pictures/Videos/Other useful Material"

This post will grow slowly, and I'll get a video up in the next few weeks, once I've got another day off work

For now, here's a couple pictures for inspiration:

my strat, with a rocker switch:


my crappy p-bass, with a momentary mini toggle:


p00fz' Epiphone LP with a nice big arcade style button:


Evil_Magician:



if you've got something you want posted, DON'T post the picture in [IMG] tags. post a link to the picture, so pages don't take forever to load with a slow connection, and there's not 2 of every picture in the thread

edit: thanks sammo

__________________
Wiring your guitar?

james4

Alright, you can post now

I'm going out right now, but I'll fix the couple broken image links once I get back

__________________
Wiring your guitar?

asfastasdark

All I'm going to say is, this thread makes installing a killswitch way more intimidating than it really is. Good thread though.

__________________
Gear:
Schecter Hellraiser Deluxe
Boss DS-1
Crate GTD65

GAS List:
Mesa Boogie Dual Rectifier Roadster

SomeoneYouKnew

*content absorbed into working posts*
[reserved for future use]

__________________

Meadows

james4

edited it in, syk

and I realized that I mention putting a really big resistor across the switch lugs to reduce popping in one of the early posts, then never talk about it further down..
i'll get to adding that in a few

__________________
Wiring your guitar?

The4thHorsemen

yea, I was wondering about that. I was just reading through to see if you forgot anything and then saw that about the resistor and got all happy cuz I've never heard of that and mine pops... then you didn't mention it anymore

__________________

wiliscool

Its thorough for sure.

Nice work James.

__________________
Member of the official GB&C "Who to Listen to" list

timbit2006

This is sweet!

I don't really need the killswitch part, but that diagram with the wiring to switches up to 4PDT really helped me out. I now know how to wire my project up!

__________________
--Tyrone the White
Canada.

GODhimself37

You never said how to wire up a button killswitch to a guitar, just switches. I happen to have a button that is exactly like the first one you showed.

Halp?

__________________

If a mortal stands before us
Strike him down with sleight of hand.
And if heaven rides against us
Then God himself must be damned.

Computer Science major! Apple enthusiast!
I wear Vibrams and type with Dvorak!

solomon684

You would wire it up the same way. If it has two lugs just wire it up the same as the switch with two lugs. There's no difference in wiring one with a button and one with a switch


Oh, and James you may or may not want to add all or some of this... I found this page very helpful to me when I added a killswitch. Very simple way of doing it, good explanation, and the last 3 pictures are very helpful
http://alexplorer.net/guitar/mods/killswitch.html

__________________
Impossible is Nothing

GODhimself37

That's exactly what I used. I just got it wired up too btw, but whenever i press it i can always kinda hear the signal get fuzzy then turn off if i don't press it fast enough. Is this normal?

__________________

If a mortal stands before us
Strike him down with sleight of hand.
And if heaven rides against us
Then God himself must be damned.

Computer Science major! Apple enthusiast!
I wear Vibrams and type with Dvorak!

SomeoneYouKnew

Not normal. Crappy switch. Use a better switch.

__________________

Meadows

SomeoneYouKnew

Lord no. That guy is an idiot. Look at his picture for a Normally Closed switch. He's breaking the ground circuit. What a buffoon!

__________________

Meadows

solomon684

Well I used the normally open picture and it worked, never used a N.C. switch, but it does say you can use the hot wire instead

__________________
Impossible is Nothing