Right off the bat, I admit to being an electronics "dummy". However, I've spent around 30 years playing with pedals, so I've learnt a few things from trial and error that have helped me now to put together some professional quality pedalboards.
I hope what I've learnt can help you too...
Tone, or Noise?
So, it's taken you countless hours to find and a lot of money to purchase an awesome collection of guitar pedals. You've also put a lot of effort and energy into planning and putting your dream pedalboard together. Then you plug your beautiful dream guitar into the input of the first pedal on your new board, out of the output of the last pedal and into your recently serviced and amazing sound tube amp, and power it all up.
But instead of getting the sweet liquid honey tone dripping from the amp speaker like you expected, your tone is weak, uninspiring, and worst of all, has a high-pitched, faint and truly vexing mosquito-like noise that just buzzes around the tone. Tears and/or gnashing of teeth ensues...
Unwanted noise like this is a regular complaint from guitar pedal enthusiasts the world over. By far the most common cause – an unsuitable power supply. I've been there before; a few times actually! When it comes to guitar pedals and electric powered musical instruments in general that have particular power requirements, having the right power supply really matters. In addition to causing unwanted noise in your signal, a bad power supply may actually damage components in the circuitry of a pedal, or in some cases, actually completely fry it!
a bad power supply may actually damage components in the circuitry of a pedal
However, there is an abundance of information out there on good clean power for guitar pedals. So much information in fact, that it is as easy to become really overwhelmed and frustrated with it as much as it is with the problem you're trying to solve! With this in mind, and rather than adding to the frustration, my aim with this article is to save you a whole lot of time and energy with a concise guide to good power supplies for guitar pedals.
There are some general facts that really help to get a workable understanding of how to power a board well which will subsequently go a long way to producing an optimum audio signal (notwithstanding having high-quality instrument cables and patch leads – that's another blog for another day). Below is a basic summary that I have compiled of the essentials to know:
- Voltage is the unit of measure that determines the battery and/or AC adaptor you need to use with a specific stompbox.
- Power from the wall GPO (General Power Outlet) is AC, varying from 100V (Japan) and 120V (USA), up to 230V (Australia and New Zealand) and 240V (Brunei).
- Power around the world also varies in frequency of 50Hz or 60 Hz, and in some countries like Japan, both!
- The power socket on your pedal is DC power, although some pedals have AC power requirements.
- Current is how much power your stompbox needs. If voltage defines the "type" of power, current defines how much of it.
- The standard measurement for current in guitar pedals and music equipment in general is milliamps (mA).
- The modern standard for power sockets in pedals is negative tip polarity and usually 9V DC. This has been standardised by the popularity of Boss Corporation compact pedals, arguably the most common guitar effects stompboxes in the world.
- There are some pedals that require positive tip polarity DC power plugs, so be very careful that you know what your pedal requires as using the wrong plug will damage and possibly kill your precious pedal! These are generally vintage-style fuzzes and the like.
- Some pedals require 12V, 18V and sometimes more, and usually come with their own power adaptors. If you want to use them with a power supply that is powering other pedals on a board, there are plug fittings that boost the power from 9V to 12V, 18V, and even 24V. Many overdrives and fuzzes run up to 18V for example, to give more "headroom". Some power supplies such as the Strymon Ojai R30 and Zuma, and the Truetone series have designated parallel outlets with specific voltages to meet this need.
- “Wall wart” is the term used to refer to standard low cost power adaptors, such as the Truetone 1Spot adaptor – the benchmark for an affordable but quality power adaptor for pedals.
- Analog overdrives, distortions, fuzzes, generally have very low current draws of less than 20mA. Most simple overdrives for example need only around 5mA of power!
- Most digital pedals need between 50 to 100mA current. The Flux Effects Liquid Ambience for example only needs 60mA and can work quite well off one of the standard outputs of any quality pedal power supply.
- Feature heavy digital pedals however from brands such as Strymon, Line 6 and Eventide require up to 400mA current, and need to be isolated (parallel). Powering these off a daisy chain from a standard “wall wart” power adaptor will conjure the noisy mosquitoes in the audio signal – SO DO NOT DO IT!
- “Dirty power” refers to bad supply from cheap unmatched adaptors or bad wiring from a wall GPO (General Power Outlet). It WILL affect your tone and cause all sorts of extra noise.
- Even cheap or low-quality general power boards have badly regulated and shielded designs, so be sure to use only good quality power boards for powering any audio equipment.
Feel free to add anything I’ve missed in the comments at the bottom of this blog page.
Having a good power supply appropriate to your pedals' requirements is essential for not only good tone, but also for avoiding damage or even destroying any given pedal's circuit. Spending a little extra money on having a good power supply can help you avoid a lot of frustration and potentially losing a lot of money! Do not under any circumstance use a cheap power supply from a general electronics store (or the like) for powering pedals – you might save a little money in the short-term, and lose a lot in the long run from pedals being damaged or killed.
Spending a little extra money on having a good power supply can help you avoid a lot of frustration and potentially losing a lot of money!
Below are some of my personal power supply recommendations for varying pedal and pedalboard requirements:
Powering One or Two Pedals
A fantastic low cost option for powering a single digital pedal—or a few low current draw analogue pedals—is the 1Spot power adaptor. It provides up to 1700mA of clean and regulated 9V DC power and can be used anywhere in the world (appropriate plug needed) as it accepts 100-240V AC power. The Combo Pack comes with selection of plugs for various non-standard power sockets, including a daisy chain.
Large draw digital pedals from companies such as Eventide, Line 6 and Strymon need to be isolated, and do not work well off the 1Spot with a daisy chain to other pedals.
The 1Spot is a great simple and affordable option for small boards that don't have power hungry digital pedals.
Small to Medium Pedalboards
The Truetone CS7 is a great solution for a small to medium sized pedalboard. If you have limited space under your board to mount a power supply underneath, then some great options are the Truetone CS6, and the Strymon Ojai and Ojai R30. All of these, as well as other highly-regarded brands such as CIOKS and Voodoo Labs, provide good clean, regulated power for pedals via fully isolated outlets.
BE SURE TO SELF ISOLATE!
Beware of all power bricks that profess to have fully isolated power outlets though – a lot of cheaper options that are marketed to have isolated power outlets do not in fact have isolated power outlets. Not all power supplies are created equal! Most of these class of pedal power supplies have options such as varying voltages from designated outputs, and some even have AC outlets for some older pedals.
This is getting into the big boys, and something like the Strymon Zuma or Truetone CS12 are needed for this size of pedalboard. These power supplies are purpose designed for big pedalboards with a lot of pedals. The Zuma is perhaps the most used large pedalboard power supply in the world, and for good reason – it is arguably the best in class.
There are a number of options in a variety of brands in this category though, with a variety of outputs, being standard 100mA outputs, larger draw 250mA outputs, and even 500mA outputs for the power hungry pedals. For example, the Voodoo Labs Pedal Power 2+ also has “sag” outputs for getting that dying battery sound that some say makes fuzz pedals in particular sound great. There are other options in this class though such as the CIOKS range that give AC power-halving switch, but still are not as flexible as the humble wall wart.
Yes, that’s a decent investment in power supply, but you’ve already invested a lot on pedals so why run the risk of killing your tone or damaging your hardware by compromising the essentials?!
What Can We Draw from This?
be sure you know what you really need before you let your wallet decide
There are also other options out there in the vast world of guitar gear, and the products listed above are a small selection of the options. However, they have their own individual limitations, so be sure you know what you really need before you let your wallet decide...
- NEVER use cheap power adaptors from electronics chain stores as your guitar pedal power supply!
- Use only power supplies designed for use with guitar pedals, or even better, the power adaptor the pedal came with.
- Only use daisy chains with low current draw pedals like overdrives, distortions, fuzzes, simple analog modulation effects.
- Ensure you know the polarity of your pedal power socket - most are 9V negative tip like Boss pedals, however do not assume this. Some vintage-style fuzzes have positive tip polarity. My general rule in life is NEVER ASSUME as powering a pedal with the wrong polarity can fry the circuit!
- Some guitar pedals require more than 9V supply, and some older models even take AC power rather than DC. Again, make sure you know what each pedal needs before you plug in and power up.
- Make sure you run power hungry digital effects off isolated outputs. Also, any analogue pedals that require over 100mA should also be powered off an isolated supply of its own.
- Pay the extra for a good power supply. Skimp on this to have more for a new guitar pedal, and you may well damage them all.
Do the right thing for your tone, extend the life of your precious guitar pedals, and respect your ears by making sure you have the right power supply for the job.
I cannot stress enough how important it is to have a good power supply for guitar pedals! Not doing so is like having cheap $50 tires on your expensive sports car, or soy milk in your coffee; it’s just, not, right. Do the right thing for your tone, extend the life of your precious guitar pedals, and respect your ears by making sure you have the right power supply for the job.
Thanks for reading and I truly hope this was helpful. Enjoy your cleanly powered tone!
PS I would also recommend referring to this article from Beavis Audio, which goes more in-depth into the electronics of guitar pedals and some great advice on batteries, not covered here (anyway, who uses batteries anymore hey!).
Originally written by Rodger van Raalte in 2014*
Owner and manager of Signal Chain
* revised and updated in August 2021