This is the Test Kitchen, so let's talk about switches! In the pedal building world we really only come across 4 different kinds of switches: toggle, rotary, push button (stomp usually), and DIP. The different kinds of switches merely indicate how you 'activate' the switch. I'll explain the types once we cover how a switch works in general.
So what exactly is a switch? A more technical answer is that a switch is an electromechanical device that (dis)connect a path in an electrical circuit and/or divert the electrical current from one connection to another.
When we talk about switches and describe them (their name mostly) we talk about poles and throws. A "pole" indicates the number of circuits/connections that switch can control and a "throw" tells us the number of contact points.
The simplest switch possible is a single pole, single throw switch. In a schematic it would look like the top diagram. This one connection is either open or closed. It is how you control the light on your workstation lamp regardless of how you turn it on (push a button or turning a knob)
You can see it is one pole because only one circuit (wire) is involved on the left (schematics tend to flow left to right). It is one throw because the switch can only control the contact point going to the output.
Here's what one looks like. It is a toggle switch and we've all seen them.
The next step up is known as a single pole, double throw switch (SPDT). In a schematic it would look like the bottom diagram.
It is one pole because because there is only one circuit involved at the 'input'. 2 throws because the switch can control the electrical flow to 2 separate contact points here. An example of this in our world may be to select the value of the output capacitor (100n vs 1n) like this.
Now that you've got the basics down let's talk about double poles. 2-pole switches have 2 separate inputs controlled at the same time. Here's a really good visualization to explain the difference when you have one or two throws. I'll let this do the talking instead of me writing it up here. If you've got questions here either write them below or message me.
Let's take the next step up. The one you all use in your pedal builds: the 3PDT stomp switch!
Using the same methodology as above, 3 poles (inputs) are controlled at the same time and is in the middle horizontal row based on the pictures above and below.
Let's walkthrough what happens on your builds when you use your stomp switch. Keep in mind this is the classic way to do true bypass here. The orange wire on the left goes to your guitar input jack and the orange wire on the right goes to your output jack to your amp.
Looing at the 'lug map' above, let's figure out together what 'position 1' does. When position 1 is activated we have 3 separate connections: 2-3, 5-6, and 8-9. 2 and 8 we have already determined that those are our input/output jacks. 5 is ground. We also see that there is a jumper wire between 3 and 9. Put these two together and we determine that the guitar signal goes into lug 2, out lug 3, into lug 9, and out lug 8. It completely 'bypasses' the circuit since no connections are being made to the PCB. Position 1 must be true bypass! What about pins 5 and 6? What are they doing here? Good question! Since 5 and 6 are connected here we can figure out that 6 goes to ground. There is a jumper that goes from 6 to 1 and 1 is the input to your PCB. We can now determine that the input to your PCB goes to ground and blocks off any noise the circuit may make.
Position 2 obviously means we activate the PCB effect, but let's walkthrough it anyways. 3 connections are made here: 1-2, 4-5, and 7-8. 1-2 means that our guitar signal is coming from the input jack into the PCB input. 7-8 is the output from the PCB to the output jack (your amp). 4-5 connects ground to the PCB, including the LED. You now have a fully connected connected pedal. We're only talking about switches here, so the DC power jack is separate.
Hopefully you've got a good understanding now of how a switch operates in terms of poles and throws. It can get more complicated in terms of the number of poles and throws, but the concept is still the same.
Now let's talk about the different types of switches.
Toggle Switches
A toggle switch in our world most commonly looks like the first picture above of a red switch (I'm running out of pics to put in here, AHHH!!). Flip the arm one way or the other to activate.
ON/ON
I will use this example of the pins here. It is a SPDT and if your switch is a DPDT also consider pins 4-6. Remember, the "pole" according to my methodology is the middle pin here (2 and 5)
1 - 2 - 3
(4)-(5)-(6)
In an on/on switch there are only 2 positions: a connection between 1-2 OR a connection between 2-3. A connection either way will always be made.
For the record you can turn ANY double throw into a single throw switch: simply omit a connection to pin 3 (and 6 if a double pole) and it's now an on-off switch. Buy extra double throws or look for a prettier looking SPST switch.
ON/OFF/ON (SPDT or DPDT for us)
In a toggle switch, there are actually three positions here that can be used, left-middle-right or up-center-down depending on how you're looking at it. Using the same example here:
1 - 2 - 3
The "on" portions we have already talked about. The middle position is what stands out and simply means that NO connection is made to either pin 1 or 3 in my example. How can this be useful? Let's say on a breadboard you have 2 sets of hard clipping diodes going to ground: D1/D2 and D3/D4. Using the far left position of the switch allows you to activate D1/D2 and the far right activates D3/D4. The middle position here actually cuts off the diodes entirely for a different sound in your circuit.
ON/ON/ON (DPDT mostly for us)
This one can get confusing. This configuration gets separated into 2 types: Type 1 and Type 2 (duh!). This was already discussed in a separate thread here but I will mention it for completeness. There are three positions: up, middle, and down. Up and down have already been covered, but the middle position is what makes this stand apart. The best way to show type 1 and type 2 is to look at the picture below. Make sure you check which type of switch you need while sourcing your parts!
Rotary Switches
Here's a Tayda link: https://www.taydaelectronics.com/rotary-switch-1-pole-12-position-alpha-srf.html
The oversimplification of a rotary switch is that it is activated when you twist the knob. Many table/desk lamps use a rotary switch but that is a single pole mostly. When you turn the knob it 'clicks' and the number of poles/throws determine how many 'clicks' the switch will have. This can get complicated quickly to determine which 'click' of the knob controls what. Use a DMM on the continuity setting to figure that out rather than me explaining that process here.
Push Button (Stomp) Switches
This is your 3pdt stomp switch used to turn your pedal on or off. I don't think I need to mention much else other than they make others that are controlled with your finger instead of your foot.
DIP Switches
Here's a tayda link: https://www.taydaelectronics.com/dip-switch-6-positions-gold-plated-contacts-top-actuated.html
These kinds of switches go directly on your PCB, are pretty small, contain multiple switches, and cannot be controlled externally once you box up your build. Think of it as an IC chip but it's only a bunch of switches on it or as a trimmer: it's kind of a 'set it and forget it' mentality here, but obviously you can go in and tweak it to your tastes depending on how these behave in the circuit.
Momentary vs Latching
Latching switches are more common for us. It simply means that when you activate a switch it stays that way until you physically activate it again. When you flip a toggle switch or step on your stomp switch you hear an actual 'click'.
Momentary switches make the (dis)connections when you push the button or toggle switch. There are springs in there to bring it back to the normal position. Think of this as a kill switch on your guitar. Buckethead has one and uses it a lot.
Is one better than the other here? There are tradeoffs and it all depends why you are using a momentary or latching switch. The best example in the pedal building world of a momentary switch is for relay bypassing. What is it and why should you care? Well, relay bypassing is a different way to hook up your 3pdt switch to achieve true bypass. Coda Effects does an excellent job of explaining it here if you're interested. This short answer is that relay bypass system with a momentary switch lasts a lot longer (allegedly) than a 3pdt latching switch, but it takes more components to make it work. PedalPCB has a few relay boards in the utility section if you want to look more into this.
So, that's it! I think I've covered just about everything I can think of when it comes to switches and guitar or bass pedals. Any comments or questions please leave below.
BuddyTheReow
€ of pedals for 10€ of power supply ?
Wondering how to choose your power supply so that your pedalboard is powered in the best way? When you start to have a few pedals, it is necessary to have an adapted power supply, to avoid all kinds of noise problems, or pedal dysfunctions.
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In this article, we will guide you towards the solution that best suits your needs, offering you various power supplies solutions adapted to what you want to do!
know your pedals
Before choosing the right power supply, you first need to know the needs of each of your pedals! We’ll give you 4 points to check for each of them, to make sure you never make mistakes.
voltage
Voltage is usually the first thing you look at on a pedal. It is measured in Volts (V). Usually it is noted next to the power connector, and this value should always be respected. If you apply more, the pedal may burn out, and if you apply less, it may not work correctly.
Most pedals operate at 9V. Some manufacturers allow a voltage range ( for example 9-18V) to get more headroom, but if this is not indicated, it is strongly not recommended!
direct or alternating current
The next thing to check is if the pedal operates in direct (DC) or alternating (AC) current. Most pedals are DC, and the few pedals that still run on AC usually come with their own power supply.
polarity
The polarity concerns the pedals running on DC, that is to say the majority! As the connector has 2 terminals, the polarity indicates which one is connected to the “+” or “-” of the power supply.
For most electrical devices, the convention is to have the “+” in the center of the connector. But a clever guy once had fun doing the opposite for pedals! As a result, most pedals nowadays have the “-” in the center of the connector, although there are still a few exceptions.
So be careful with power supplies found in supermarkets or at the bottom of a cupboard! A pedal powered with the wrong polarity has a big chance to burn out. It is better to use the ones designed for effect pedals, and check that the polarity symbol on the power supply is the same as on the pedal.
current
Current is measured in Amperes (A), but since effects pedals are low power consumption, it is more often measured in milliamps (mA), a milliamp being times less important than an ampere. The important thing to remember is that a power supply only provides the current that the pedal needs. We often hear “if I connect a 50mA pedal to a 2A power supply, the pedal will burn out”. But it doesn’t work like that!
The current written on a power supply corresponds to the maximum current it can give. By connecting a 50mA pedal, the power supply will only give out 50mA, even if it is written 2A on it! You should therefore choose a power supply with an indicated current higher than the sum of the currents of all the pedals.
If you have checked these 4 points on your pedals, then you can be sure that you won’t make any mistakes! We can move on to the next part.
a summary of the power supply technologies
We wrote a whole article about power supply technologies in detail. But we’ll summarise it quickly so that you know the essential differences between the power supplies on the market.
galvanic isolation
Galvanic isolation is made with a transformer. Each output, or output block, has its own transformer, so there is no electrical connection between the isolated outputs.
The big advantage of this technology is that it avoids ground loops between the pedals, which acts as light antennas. So no noise coming from the outside (electrical devices near the pedalboard, electromagnetic waves…).
On the other hand, transformers operate on AC, which means that the AC/DC conversion is done directly in the power box. The 50/60 cycle from the mains socket runs close to the pedal outputs, and can be captured by radiation. It is an audible frequency, which is responsible of the famous “hum” noise of electrical devices.
If you want to learn more, please visit our website Pedal Switch Supplier.
Galvanic isolation also does not allow very high currents at the output, which makes it impossible to power pedals that require a lot of current.
switched-mode power supply
This is the technology we decided to go with. It works in DC, so we can do the AC/DC conversion in an external housing, away from the power supply and the pedalboard. Then, we have a chip on each output or output block which cuts the signal at high frequency (inaudible frequency) to drop the voltage to the desired value.
This chip makes it possible to create a pseudo-isolation, i.e. each output is isolated in voltage, but still has a common ground. So we have a ground loop unlike galvanic isolation, but we still avoid perturbations between the pedals. And above all we completely suppress the 50/60 cycle responsible of the ” hum ” noise, which is a much more important source of noise than the noises that can be picked up by the ground loop!
In addition, the switching makes it possible to obtain higher currents at the output, enough to power the most demanding pedals.
choose the correct power supply
We’ll help you to choose the best power supply solution, depending on the board you have or plan to make!
analog pedals
You only have 3 or 4 analog pedals? In that case, a power supply like the 1 Spot with a daisy chain is more than enough! Analog pedals require very little current, usually a few dozen mA, and are not a source of noise. So if you don’t have a lot of them, you don’t need a power supply with isolated outputs.
the positive ground
This is a rare case that mainly concerns a few vintage fuzz pedals. The electronics in the pedal do not take the “-” of the power supply as a reference, but the “+”. This is an even different case than polarity inversion, which requires that the ground of the pedal be completely isolated from the other pedals.
Many people power these pedals with a battery, as they often consume less than 10mA. To use a power supply, you need galvanic isolation with a transformer, so either a 1 Spot dedicated only to this pedal, or use a power supply with galvanic isolation, like most Cioks.
digital pedals
Do you have a mix of a few analog and digital pedals? Digital pedals consume more than analog pedals (a few hundred mA). But above all, they can be a source of noise, which will diffuse into the power supply and to other pedals if they are not isolated from each other.
The solution would be to use a 1 Spot with a daisy chain only for analog pedals, then one 1 Spot per digital pedal. This can be expensive, cumbersome and not very practical.
Otherwise, you can do things more properly and invest in a small power supply unit. Any power supply unit is suitable for this!
tube pedals and preamps
We’re coming to the most current-consuming pedals! Pedals with tubes generally require around 1A and even 2A in some cases, so you need a power supply that can do the job! That’s why we’ve managed to ensure that our power supplies can draw as much current as possible.
space pedalboard
Do you collection pedals of all kinds? You need a complete power supply with enough outputs for all your pedals. We propose you the Cioks Ciokolate, limited in current but enough for most pedals, with AC outputs.
Or our K+ bundle, if you have a tube preamp or a pedal that requires a lot of current. On top of that, you have 2 modules, which you can position wherever you want on your board, or make 2 separate boards that you can link together!
to sum up
We give you a table to summarize which power supply you should choose according to your needs. And don’t forget to always check voltage, polarity and current on a pedal before plugging it in!
You are also invited to watch this tutorial made by the wonderful Colin Scott, it will be very helpful for you to understand it all!
Contact us to discuss your requirements of Safety Limit Switch. Our experienced sales team can help you identify the options that best suit your needs.
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