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With as many effects on the market, the need for noise-free guitar pedal power supplies is at an all-time high. Manufacturers are making effects that have some of the best sounds ever created. But the need for more advanced circuits has become the only way to compete as a pedal maker.
Here are my 10 recommendations for best power supplies:
- Truetone 1 SPOT PRO CS12.
- Voodoo Lab Pedal Power Mondo.
- MXR ISO-Brick.
- Friedman Power Grid 10.
- Strymon Zuma.
- Mission Engineering 529i.
- Voodoo Labs Pedal Power 2 Plus.
- Strymon Ojai.
- Pedal Power ISO 5.
- Voodoo Lab Pedal Power X4.
Top Choice
1 SPOT PRO CS12
Next Best
MXR DC Brick
Best Guitar Pedal Power Supplies
Once you realize your needs, you can then select the correct guitar pedal power supply for your rig. There are great pedal board supplies as well as stand-alone units.
If you want more information and are not quite sure what you need, please continue reading. We have created a guide to help you right after our recommended power supplies.
Our guide will cover all the basics and more. We encourage you to read up if you want to learn more about guitar pedal power supplies!
We have also given each supply a rating in certain categories. They are rated between 1 and 5. The higher the number, the better they did! If you’re ready to check out the products we recommend, let’s go!
Truetone 1 SPOT PRO CS12
The Truetone CS12 is one heavy-duty guitar pedal power supply! It’s capable of 3000mA of current. Has 12 isolated outputs that provide multiple voltage options. Plus, it comes with pedal train mounting brackets and cables.
There is also a 9V AC output to truly cover all voltages that you might find on commercial products. There are a few switchable outputs that can be set to either 9 or 12 volts from a toggle on the bottom of the unit. And a variable output that can be set to 4 volts if desired.
The supplied cables will also aid in getting pedal polarities correct. This is one serious supply for optimal performance! When we used it to power our pedal board filled with 10 various devices, we had no issues. Each device was drawing the required power and there was no added noise to any of the outputs.
Features
- Isolated power supply.
- Variable voltage control.
- Switchable voltage options.
- Includes cables.
- Includes mount brackets.
- Size: 8.12″ x 3.37″ x 2″.
- Weight: 2.3 lbs.
- Manual.
Outputs
The Truetone 1 SPOT PRO CS12 power supply is designed for large boards with multiple pedals and devices. It features 12 fully isolated outputs that provide clean and noise-free power to your pedals. Here is what you can expect:
- 9 Volts at 250mA.
- 9 Volts at 500mA.
- 18 Volts at 100mA.
- 9 Volts AC at 800mA.
- 9 or 12 Volts at 100mA.
- 4 to 9 Volts at 100mA.
What Is The CS12 Best Suited For?
For players with a huge pedalboard, the Truetone 1 SPOT PRO CS12 is a fantastic option! It’s made to give your pedals dependable, noise-free power. But while ensuring that you get the best possible sound from your equipment.
The CS12 is capable of delivering up to 500mA of current from some of its outputs! This is more than enough to power even the most demanding pedals! You will also find other voltage options, making it compatible with a wide range of devices.
The Truetone CS12 is the perfect device for use on the road because of its small size and low weight.
Are you a professional musician in need of a dependable and superior power source? The Truetone CS12 is a great option that will satisfy all of your demands.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 3.5 |
| Variable voltage options | 5 |
| Build quality | 5 |
| Size | 4 |
| Affordability | 3.5 |
Build Quality
The build quality of the CS12 is top-notch! The unit features a heavy-duty aluminum enclosure that is both sturdy and lightweight. The power supply is fully isolated. This helps to prevent any noise or hum from entering your signal chain.
Additionally, the CS12 has a compact design that makes it easy to fit on your pedalboard. Each input creates a solid connection thanks to the quality materials. Each cable is thick and ready for the rigors of high current operation. It’s a well-made device!
CS12 Vs the Fender Engine Room
For context around the CS12, let’s compare it to the Fender Engine room.
Both devices provide clean power and several isolated outputs. However, there are some significant distinctions between them. The Truetone has 12 isolated outputs with variable current ratings. It’s a decent amount of power! It also has a range of voltage options and is built with a compact and lightweight design.
On the other hand, the Fender Engine Room features 8 isolated 9V outputs. With 6 providing up to 500mA of current! You will also find 18V, 12V, and 6V outputs. It also has built-in LED lights for visual indication of current usage.
Both power supplies are well-built and offer reliable performance. But the CS12 is very versatile with more outputs. The Engine Room having more powerful outputs and built-in LED lights.
Voodoo Lab Pedal Power Mondo
This is one heavy-duty quality power supply! It’s capable of some very high current, allowing a majority of 9-volt devices to be used. If it requires anything more than what this unit can deliver, it probably shouldn’t be on your board!
With 10 devices loaded up on the pedal power Mondo, I was able to satisfy all my requirements. Plus, I experienced good operation from each pedal. They all responded as they should and there was zero added noise.
I also daisy-chained 4 pedals together using one of the high-current outputs. The performance was rock solid.
This unit also has a sag option that simulates a dying battery. This is because some pedals sound perfect when the battery is less than half of its capabilities. Using an overdrive with a sag output, I was in fact able to hear a difference in how it performed.
Features
- Isolated, fan cooled, power supply.
- High current outputs.
- Sag simulation.
- Includes various cables.
- Toroidal transformer for low noise.
- Size: 10.75″ x 3.4″ x 1.87″.
- Weight: 2.9 lbs.
- Instruction Manual.
Outputs
The Mondo has more than enough outputs and variation. This supply was designed for large boards with many pedals and devices. Here are the power connection outputs found on the Mondo and their amperage capabilities:
- 9 or 12 Volts at 400mA.
- 9 Volts at 400mA.
- 9 or 12 Volts at 100mA.
- 9 Volts at 250mA.
- 9 Volts or SAG at 100mA.
What Is The Mondo Best Suited For?
The Voodoo Lab Pedal Power Mondo is best suited for guitarists or musicians who use a lot of effects pedals. It has the ability to power up to 12 pedals simultaneously! This makes the Pedal Power Mondo perfect for large pedalboards. Or use it for a variety of pedals with different voltage and current requirements.
It has multiple isolated outputs and adjustable voltage and current option. This makes it compatible with almost any type of pedal! All from standard analog stompboxes to digital multi-effects processors. The Pedal Power Mondo is also ideal for those who demand clean, noise-free power for their pedals.
Ground loop-related hum is eliminated by its sophisticated filtering and regulating circuits.
Because of this, it is a dependable option for experienced musicians! Those that demand the highest level of quality from their effects pedals. The video below is a great example of how this power supply can help you.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 3.8 |
| Variable voltage options | 5 |
| Build quality | 5 |
| Size | 4 |
| Affordability | 3.1 |
Build Quality
After using the Voodoo Lab Pedal Power Mondo for a while, I can attest to its exceptional build quality. The metal chassis is extremely rugged. It can withstand the wear and tear of frequent gigging and touring. The unit is also relatively heavy! This gives it a reassuring sense of stability on the pedalboard.
Another significant advantage is the internal heat-dissipating technology of the device. Any overheating problems will be avoided, especially during extended use. The Voodoo Lab Pedal Power Mondo is a wonderfully built power supply!
Voodoo Lab Mondo Vs T-Rex Fuel Tank
The T-Rex Fuel Tank and the Voodoo Lab Pedal Power Mondo are both excellent power supply devices. But let’s compare the two in order to understand the Mondo better. Here are some of each product’s pros and cons:
The ability to power up to 12 pedals at once is a benefit of the Voodoo Lab Pedal Power Mondo.
It goes beyond the T-Rex Fuel Tank. It also has a greater range of voltage and current options. This is perfect when you need to accommodate a wider variety of pedals.
The Mondo is recognized for its cutting-edge control and filtering circuitry. Yet, the Pedal Power Mondo is larger and heavier than the T-Rex Fuel Tank. For artists that need to minimize the amount of space on their pedalboard, this can be a problem.
MXR ISO-Brick
Features
- Isolated power supply.
- Variable voltage control.
- Switchable voltage options.
- Includes cables.
- Includes adapters.
- Size: 4.7″ x 2.9″ x 1.8″.
- Weight: 1.8 lbs.
- Manual.
Outputs
- 9 Volts at 100mA.
- 9 Volts at 300mA.
- 9 Volts at 450mA.
- 18 Volts at 250mA.
- Variable 6 to 15 Volts at 250mA.
What Is The ISO-Brick Best Suited For?
A great option for pedal boards that require conventional voltages with minimal variation. This is a great supply for mid-sized boards.
The MXR Iso-Brick power supply is another high-quality unit for noise-free operation. The Iso Brick is capable of a 2000mA from 10 isolated outputs. It can provide a range of DC voltages. And with variable options from 6 to 15V DC.
This is another unit that will provide all the DC voltage requirements you will need for your pedals. This unit is very sleek and easy to mount to many boards.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 4 |
| Variable voltage options | 4.5 |
| Build quality | 5 |
| Size | 5 |
| Affordability | 3.5 |
Friedman Power Grid 10
Features
- Isolated power supply.
- 10 output power supply.
- Includes cables.
- Ultra quiet operation.
- Size: 4.5″ x 6.75″ x 1.75″.
- Weight: 1.5 lbs.
Outputs
While the supply only provides 9 volt power, you can expect 350mA per output.
What Is The Grid 10 Best Suited For?
This is a great supply for players who need a basic 9-volt. This is perfect for a mid-sized board that uses basic effect pedals. While the Friedman power grid 10 is a very simple supply, we chose it because of its dead-quiet operation.
This unit offers a simple 10 outputs at 9V DC and is designed to be very basic. It will supply most pedals on the market, but unlike other isolated power supplies, this one is quiet. So if you have very sensitive devices that seem to be noisy even with an isolated power supply. This will be the model for you!
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 5 |
| Variable voltage options | 1 |
| Build quality | 3.5 |
| Size | 4.5 |
| Affordability | 3.5 |
Strymon Zuma
Features
- Fully isolated power supply.
- 9 outputs.
- 48 Watt maximum output.
- 2 voltage selectable outputs.
- Cables included.
- Size: 6.8″ x 3.3″ x 1.8″.
- Weight: 1.25 lbs.
Outputs
- 9 Volts at 500mA.
- Adjustable: 9, 12, and 18 Volts.
What Is The Zuma Best Suited For?
Perfect for pedal boards that have power-demanding devices. The ability to add on more power supply attachments makes this a smart choice.
Strymon has been making awesome products since the beginning. The Zuma is no exception. The anodized aluminum case looks great, just like their other pedals. Their platform allows you to add more supplies and chain them together is genius.
This allows players to start with the needs of their current pedal board, but add more as they go along. This model is capable of a stunning 48 watts of power, which will happily power your devices all day long.
2 adjustable outputs are very convenient. Sometimes certain devices require more voltage to operate. When connected to our pedals and devices, they were all running noise free. The Zuma is double isolated and so this is about as quiet as it gets.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 4 |
| Variable voltage options | 3.5 |
| Build quality | 4 |
| Size | 4 |
| Affordability | 3.5 |
Mission Engineering 529i
Features
- Rechargeable Isolated power supply.
- 8 outputs.
- Internal battery to power without external supply..
- High current.
- Cables included.
- Size: 5.5″ x 2.75″ x 1.25″.
- Weight: 1 lbs.
Outputs
- 9 Volts at 500mA.
- 9 Volts at 300mA.
- 5 Volts for USB.
What Is The 529i Best Suited For?
Wonderful for a player who needs a supply that also holds a charge. With a built-in battery, you can use this supply away from mains power.
The 529i is a different concept than the rest. With this device, you charge the battery first and then use it to power your pedals. This is great for anyone who is going to need a supply that is self-sufficient.
With a run time of 4 hours at 500mA loaded, you have a ton of time to power before needing a recharge again.
When using this supply on my board, I was able to get clean, noise-free power for all the pedals. There is even a 5-volt USB connector that I was able to use to power my lighting. This way it doesn’t take up a valuable output, just for lighting.
The size is very small, and it’s light, which is great for mounting under smaller boards where space is tight.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 3.5 |
| Variable voltage options | 2.5 |
| Build quality | 4 |
| Size | 4 |
| Affordability | 4 |
Voodoo Labs Pedal Power 2 Plus
Features
- Isolated.
- Short Circuit Protection.
- Variable outputs.
- Switchable Outputs.
- Cables included.
- Size: 3.4″ x 6.1″ x 1.75″.
- Weight: 2 lbs.
- Manual.
Outputs
- 9 and 12 Volts at 100mA.
- 9 Volts at 250mA.
- 9 Volts at 100mA.
What Is The Pedal Power 2 Plus Best Suited For?
Best for anyone who needs a 9-volt supply for a mid-sized pedal board. There is also one 12-volt output for any variation.
The Voodoo Labs pedal power 2 plus is a very dependable and quiet supply. It’s capable of many voltages, even variable, which is called “sag” on the unit. Changing between them is done using the switches on the bottom side of the unit.
The device is built with a toroidal transformer. According to Voodoo Labs is the secret to the quiet operation it offers.
It offers 8 outputs for a total of 1100mA max for the brick, and for a lot of players will be plenty. If there is any reason to ever need to replace this unit, it will simply be for more outputs.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 4 |
| Variable voltage options | 3 |
| Build quality | 3.5 |
| Size | 4 |
| Affordability | 4 |
Strymon Ojai
Features
- Isolated supply.
- 5 outputs.
- High current outputs.
- Can daisy-chain more Ojai’s.
- Very quiet.
- Cables included.
- Size: 3.2″ x 2.3″ x 1.3″.
- Weight: 1 lbs.
- Manual.
Outputs
This is a very powerful platform. Thing is, you only have 9 volt DC outputs. But each one can handle 500mA of current.
What Is The Ojai Best Suited For?
Great unit for pedal boards that need 9 volts with high current capabilities. This design also provides the opportunity to combine with add-ons to increase capabilities. This is convenient as your pedal board grows.
The Strymon Ojai is one very neat little design. This unit, while simple, can handle 500mA per output!
What is really cool about it, is that you can connect more Ojai models together to expand your outputs. A player can start with a small board and upgrade later. Then you can buy another Ojai and connect the two together. This will expand the number of power options!
Strymon has also built this unit to be very easy to mount due to its size, but it’s also super light! And somehow it can supply current by the boat load. The only limitation is that you will only get 9 volts from each output, but for a lot of players, this is no big deal.
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 5 |
| Variable voltage options | 2 |
| Build quality | 3.5 |
| Size | 5 |
| Affordability | 3.5 |
Pedal Power ISO 5
Features
- Isolated power supply.
- 5 output jacks.
- High current output.
- Multiple voltages.
- Very quiet.
- Cables included.
- Size: 4.9″ x 3.4″ x 1.8″.
- Weight: 1.25 lbs.
- Manual.
Outputs
- 9 Volts at 100mA.
- 9 and 12 Volts at @ 400mA.
- 18 Volts at 100mA.
What Is The ISO 5 Best Suited For?
Good for smaller pedal boards with only a few devices. The opportunity to use different voltages is available, but the outputs are limited. The Voodoo Labs ISO 5 is a great offering for those players who don’t have a lot of pedals and just need a simple supply.
This unit is very quiet and gets the job done. While still offering a high current output and some common voltage options. It’s small, light, simple, and easy to mount. Need a simple, quiet power supply? You found it!
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 4.6 |
| Variable voltage options | 3.4 |
| Build quality | 3.6 |
| Size | 4.4 |
| Affordability | 4 |
Voodoo Lab Pedal Power X4
Features
- Isolated power supply.
- 4 outputs.
- Very quiet.
- Cables included.
- Size: 3.37″ x 2.75″ x 1.6″.
- Weight: 1.25 lbs.
- Manual.
Outputs
This little unit is very simple. But you can only expect 9 volt DC outputs.
What Is The X4 Best Suited For?
Good little option for players who have up to 4 pedals that require a basic 9-volt output. The pedal power X4 is small and so there is no need for a board with this one.
Another Voodoo Labs masterpiece! This unit is for those who have minimal pedals but still want optimal performance. Being an isolated power supply, the dead quiet performance is top-notch. And being as small as it is, this model is easy to mount and very portable!
Ratings
| Feature | Rating |
|---|---|
| Ease of use | 4.5 |
| Variable voltage options | 1.5 |
| Build quality | 3 |
| Size | 4.5 |
| Affordability | 4.5 |
Power Supply Buying Guide
When it comes to selecting a guitar pedal power supply, there are a few things to consider. If you are new to this, now is a great time to learn about how this works and why it’s important to know!
Selecting the right supply to work with your pedals is important for performance. But for correct polarity as well.
Purchasing a pedal with a plug that is wired in reverse polarity could do damage. And most manufacturers will not repair it under warranty if you damage it this way.
So it’s very important to know these things to make sure you don’t cost yourself more! Especially when you could have just spent some time reading this guide!
How Much Power Do You Need?
Some of the reasons a user ends up with a poor-performing power supply is because they don’t know any better. I mean, let’s face it, we are guitar players and while some of us are electronic engineers, the majority are not.
So let’s consider your needs. This is really the only way to get the right guitar pedal power supply for your devices. Once we find out what you require, our list of the best supplies will be easier to navigate.
Here are some of the things to consider when selecting a supply:
- Number of pedals you want to power (Both current and future units).
- Voltage requirements of each device.
- Current requirements of each unit.
- Will it mount to a pedal board?
Number of Pedals
This is one of the more important things to consider. With every additional devices you run, the more you want to make sure your pedals have isolated power.
You may have heard the term isolated supply. This means each pedal will have its own power source and is not sharing one with another. The advantage of this could mean no hum or buzz.
Voltage Rating
Every guitar pedal will require a certain voltage rating. The more common are 9, 12, 15, and 18 volts DC. 90% of all devices will use 9 Volts DC. So this is a more common voltage rating found from wall warts as well as isolated power supplies.
You will always want to match the voltage that your pedal requires with the correct output. If you are not very experienced with them, then just simply match the voltages. No more, or less, otherwise this could result in damage to the pedal.
If you know that you have a distortion stomp box that sounds better when its supplied voltage is lower than recommended. Then get a power supply with variable control or a sag feature. Also, be aware that some pedals might require an AC voltage instead of a DC.
Amperage Rating
Current or amperage requirements differ greatly. Some analog pedals require very little to operate, while some digital devices need a lot! It’s recommended that when sourcing a power supply, you find out what your pedals will need for current.
A current starved unit will not operate correctly, leading to poor results. Another issue with using an underrated power supply is that you could do damage to it by asking for too much. Overheating will result when using an underrated model, causing it to burn out and fail.
So you want to make sure that your device can provide what the pedal needs or more. If you have a supply rated for 800mA and your model requires 50mA to run normally, this is great!
You will not do damage to your pedal if it’s capable of more current. You want your model to either match what the needs or more. Much more is ok too.
The pedal will simply take what it needs, and the power supply will run cool and happy. Not sure how to find out what is required?
1 Spot makes a great current measurement meter that you can use to test this. It also doubles as a cable tester too. It’s a super handy tool to have around and is suggested if you own pedals.
While most pedals run on 9 volts DC, some have other requirements. Sometimes you may find some that require 12 or even 18 volts DC. And sometimes you may find some that need 12V AC!
You will want to make sure you know what your voltage requirements are from your pedals. This way, you get what you need. Do not just assume it will run on 9 volts DC.
Pedal Board Mounting
Size matters in this regard. If you are going to run a smaller pedal board and buy an extra-large supply, it may not mount the way you might have hoped.
While buying a big power supply just in case is not a bad idea, you do want to make sure it fits onto your board. The right pedal board power supply will be different for every setup.
Benefits of a Good Power Supply
There are a number of reasons why a guitar pedal power supply is needed. But we are going to touch on the more commonly talked about reasons.
Economical
The question comes up on forums all the time, why have a power supply at all? Don’t most pedals use batteries?
And yes, there are many pedals that use batteries. In some cases, this can be handy but is not economical. With the great power supplies available today, batteries are really no longer needed. There are more manufacturers making pedals without compartments for them.
Let’s face it, that can be expensive! Not only that, they get thrown away and end up in landfills. Power supplies can be used to do the same thing as a dying battery to get that brown sound.
Get a device with a variable output. You basically have the same thing without the expense and hassle of batteries.
Prevent Unwanted Noise
Another reason to have a good isolated power supply is to prevent unwanted noise. Daisy-chaining pedals together and powering them with one adapter is a bad idea.
Can it work? Oh yea, there are some stomp boxes that are not as sensitive and can share a supply all day long. But if they don’t, do you know how to troubleshoot that? Do you know if the pedals are performing optimally daisy-chained together? Most players do not.
Most players blame their amps or pedals for the buzz or hum they hear, when really it’s the power supply. By using a high-quality isolated model, you will get a far better experience overall.
Connection Methods
As we mentioned throughout this guide, there are two main types of connection methods used to power pedals. Daisy Chains and isolated connections. They are both used. There are products on the market to provide both options.
But is one better than the other? Which one should you use?
Isolated
An isolated connection provides a pedal with its own power source. This means it’s electrically separate from any other. Types of isolated outputs would be a wall wart that services ONE pedal. The models we recommended provide isolation between each output.
When an output is isolated, it’s powering one pedal. But this also keeps the current and voltage supply consistent. But most importantly, it prevents unwanted noise.
When dealing with an audio product, you do not want noise! This can consist of buzz, hum, interference, and more. Some are more sensitive than others, and so issues can travel downstream into others.
When isolating a pedal to its own power source, you will get great results.
Daisy Chaining
Daisy-chaining is the method of connecting pedals together at their power input. Normally supplying them from one adapter which you plug into the wall.
This method can work and could be a source of clean, quiet power. But if a noisy pedal is used in the chain, this can potentially work its way into the rest of the effects as well.
Another disadvantage is that the current through it increases. This means the total sum of all device current requirements adds up. In some cases, may even surpass what the output can supply.
This can cause damage or provide poor results to the entire chain of pedals if the user is not aware of this. Our recommendation is to use isolated outputs for each unit for the very best results.
Correct Polarity
Polarity is very important with guitar effects pedals. There are several people who do not realize this is something to watch out for. There are 2 connections that are made when you plug your barrel jack into a pedal.
These are positive and negative connections. The barrel jack on a power supply could be wired differently depending on the device. So you have to verify if the polarity matches that of your pedal.
If the polarity is not correct and reversed, you can expect damage to result.
These are the symbols you want to look for when trying to find polarity. Most power supplies will have these diagrams on the unit itself or in the instruction manual.
Most effects pedals will also have these symbols marked on them. Or they can be found from the manufacturer. You will need to verify that the devices have the same polarity and markings.
This will verify that the polarity is the same and correct. If your power supply has the opposite symbol, do not use it in this case. They have to be the same!
The most commonly used configuration is a negative pin and positive sleeve. If you don’t have the right one, a Mr. Power converter cable will change the polarity.
FAQs
Below you will find answers to the most frequently asked questions.
Do Guitar Pedals Come With Power Supplies?
Sometimes a device will come with a specific power supply. But this is only the case when it might be hard to come by and not universally accepted.
If a device is designed to use a common power supply, it will not come with one. The reason manufacturers do not provide them is that most players use more than one pedal. When they do, one power supply is used for all of them.
If every manufacturer supplied one, the cables and cords would be messy and hard to deal with. If a player uses more than one pedal, they will normally opt for a power supply brick. This makes things easy and keeps cables down to a minimum.
How do I stop my guitar pedals from humming?
If you have many daisy-chained pedals and one power supply, the first thing you want to do is remove a pedal. But one at a time.
If this doesn’t reveal the issue, you can also use batteries in each of the pedals to see if the power supply is the issue. This is also a great way of tracking down the noise. Do one at a time. It will allow you to see if it’s only one device.
If you can afford to, buy yourself a high-quality model right from the start and isolate each pedal. This will help you eliminate the unit as the issue with hum. Remember, there are other things that can cause hum, but start with the power source.
Also, if you’re running more than one pedal in a 4 cable method configuration, you may have to test all cables as well.
Is it OK to use a higher current rating?
Yes, using a power supply with a higher current rating is completely fine and suggested. If your pedal is rated at needing 50mA, then you will want that or more. If this means that you use a model rated at supplying 2 amps, that is fine! The pedal will simply take what it needs and leave the rest.
The issue with current only applies if you are not giving the pedal what it requires. For example, powering a pedal that needs 500mA with a supply that can provide 250. It will try and give the 500mA, but fail in doing so. You can guarantee it will overheat.
So always makes sure to provide your devices exactly what they need or more. If you are daisy-chaining, make sure to add up each pedal’s current requirement. Then provide a unit that can cover it all.
