About Isolation... For Your Power, What Did You Think I Meant?

For those of you who have pedalboards of any size, I'm sure you're aware of the debate around pedal power supplies.  In fact I'm willing to bet that if you're reading this there's a pretty good chance that you've already picked a side.  Whether you're on team daisy chain or whether you swear by isolated power bricks, today I'm going to present the arguments for both and share what I've learned in the hopes that maybe it will help you make some more informed decisions the next time you inevitably find yourself sitting on the floor surrounded by pedals, re working your pedal board yet again.  

Daisy Chains

What Is A Daisy Chain?

A daisy chain is a simple device that consists of a wall wart (a two pronged AC adapter that connects to an electrical outlet on a wall or stage floor) and a cable that runs from the wall wart and hooks up to the power output of your effects pedal.  The best daisy chain power supply on the market these days is the 1spot by Truetone.


These power supplies are compact, affordable, and reliable.  The 1 spot as it comes in the box is capable of powering just one pedal, however you can power a great deal of pedals at once by connecting small extension cables that will allow you to "daisy chain" the power supply to provide power to several pedals at once.  


When you daisy chain your power supply in this way, each pedal's power input and output are connected, and they also have a common ground.  

Why Do Some People Prefer Daisy Chains?

There are a lot of reasons to like daisy chains.  First and foremost, they are usually more cost effective than isolated power supplies.  If you go out and buy a new pedal that you want to put on your pedal board, all you need to do to connect it to your daisy chain is pick up another extension for the daisy chain if you don't already have one laying around.  

Second, daisy chains are simple.  As long as your pedal runs off of 9v and doesn't draw an outrageous amount of mA's daisy chain power supplies like the 1spot can handle it.  Even if you're looking to power something more demanding like the Line 6 M9, the 1spot has lots of adapter cables and voltage doubler cables that are intended to support the higher power requirements present in these pedals.

One thing I've always found to be really cool about the 1spot is that it can handle different voltages from wall outlets without a transformer.  This means if you live in North America where the power from the wall is 100-110V and you're planning to do small club or bar dates in Europe where the power is 220-240V, you can just bring your 1spot and an adapter and play the gig like normal without needing a transformer.  

Why Do Some People Avoid Using Daisy Chains?

While daisy chains can be the right choice for some pedal boards, there are some issues that can arise when all the pedals in a signal chain have connected power inputs and outputs, as well as a common ground.  

One such issue involves ground loops.  Daisy chaining pedals together can cause ground loops, which can introduce hum and unwanted noise into the signal path.  In certain cases, ground loops can even be detrimental to your pedals or other electronic equipment. 

Another issue that daisy chaining pedals can create involves digital effects.  Many modern digital effects pedals have complex CPUs inside that perform tasks such as rapid switching that can produce high pitched frequencies.  In order to prevent these frequencies from entering into the guitar's signal path, these digital effects units will include a filter that removes the frequency before it reaches the output of the pedal.  If however, you daisy chain such a pedal together with an analog pedal like an overdrive, this frequency can travel through the power output and into the analog pedal (which does not include any filter for this frequency) and from there it can enter into the signal path of the guitar.  

For these reasons, many people who have a variety of digital and analog pedals on their pedal boards prefer to use isolated power supplies to power their effects.

Isolated Power Supplies

What Is An Isolated Power Supply?

Isolated power supplies have dedicated, unconnected power outputs and grounds for each pedal connected to it.  See the diagram below for a visual comparison.

There are lots of high quality isolated power supplies on the market today, but before you go ahead and make any purchase, make sure that the power supply you're interested in is capable of handling the power requirements of your pedal board.  



Why Do Some People Prefer Isolated Power Supplies?

Isolated power supplies provide dedicated power outputs and separate grounds to each pedal connected to it.  This will reduce hum and improve the performance of all the pedals on your pedal board.  Additionally, isolated power supplies are often much better equipped to handle specific power requirements from pedals that draw a lot of current or require more than 9V.  Many isolated power supply units are able to handle higher power requirements without the need for additional adapter cables or voltage doublers.  

If you currently daisy chain your pedals together, you may one day come across a pedal that you will need to plug into the wall separately from the others if you want to use it without introducing noise into the signal.  In this situation, there is almost always an isolated power supply available that will suit your specific needs and eliminate the need to use two power outlets.  

Is There Any Down Side To Isolated Power Supplies?

The biggest downside to using isolated power is that you need to ensure the unit you are purchasing will meet the requirements of all of the pedals you intend to connect to it.  And even if you find the perfect power supply and turn around and buy another new pedal with crazy power requirements, you will have to do some problem solving in order to fit it onto your board without buying a new power supply.  

One down side to isolated power supplies is quickly becoming a thing of the past.  Twenty years ago, most isolated power supplies occupied a great deal of pedal board real estate.  Today however, there are many newer models that are becoming more and more compact.  There are even power supplies that can run off of batteries or can connect via USB.  

A final downside to isolated power supplies has to do with purchasing these units online.  It is very important to purchase isolated power supplies from trusted reputable brands in the guitar community.  Earlier in this article I posted three models, one built by Truetone, one by Strymon and one by Voodoo Lab.  All of these manufacturers are trusted and reliable.  There are many listings on Amazon and other online retailers for isolated power supplies that are in reality not isolated at all.  Be careful when buying low cost isolated power supplies from unrecognizable manufacturers!

That's it from me, thank you again for checking out my thoughts on this subject.  Feel free to reach out with any questions or concerns, and as always thank you for allowing me to be a super small part of your journey with the guitar, its a privilege I do not take for granted :)