Cheap vs Expensive Pedalboard Power Supplies: What’s the Real Difference?

Rich Cattell
May 30
6 min read

Guitar Effects Pedalboard with Parallelarator pedal

When you're putting together a pedalboard, it’s tempting to focus on the fun stuff—your fuzz, delay, or modulation pedals. But there’s one essential piece of gear that often gets overlooked: the pedalboard power supply. Whether you're gigging every weekend or just jamming at home, your power supply can make or break your entire setup.

A common question we hear: “Is there really a difference between a £20 power supply and a £200 one?” The answer is yes—and here's why it matters.

What Does a Power Supply Actually Do?

Your pedals need electricity to function—but not just any electricity. A power supply provides the correct type of power to each pedal. Here’s a quick breakdown of the three key things every guitarist should understand:

🔌 Voltage (V) – Think of this as water pressure.

Most pedals run on 9 volts, but some need 12V or 18V. Too little voltage and the pedal won’t work. Too much, and you could damage it.

Check the label or manual on your pedal to find its voltage requirement.

🔋 Current (mA) – Like the flow of water.

Measured in milliamps (mA), current is the amount of power a pedal draws. A simple overdrive might use 20mA, but a digital delay could need 300mA or more.

Your power supply must deliver at least as much current as the pedal needs. More is fine—less is not.

⚠️ Polarity – The direction of the power flow.

Most pedals are centre-negative (a symbol like ⊖●⊕), but some are centre-positive. Using the wrong polarity can instantly damage a pedal.

Always double-check before connecting power.

Cheap Pedalboard Power Supplies: What You Get

Budget power supplies often come with daisy chain cables, where multiple pedals share a single power line. These are fine for small, simple boards—but they come with real downsides:

❌ Noise & Hum Across the Board

Without isolated outputs, any noise from one pedal can spread across your whole board. This is especially common with digital pedals.

A single noisy pedal (like a reverb or delay) can cause hum, whine, or buzz—even if it’s turned off—because the interference travels through the power, not the audio.

⚠️ Voltage Drop & Power Strain

Daisy-chained pedals fight over the same power source. If one demands more, others might suffer with weak signal or strange behaviour.

🔗 No Electrical Isolation

Ground loops and interference become a real risk—especially when mixing analog and digital pedals.

🔌 Basic Protection

Cheap supplies often lack voltage regulation or reverse polarity protection. A short or mismatch can lead to fried pedals.

🧱 Wall Wart Power Bricks

Most cheaper supplies use bulky “wall wart” power bricks—the kind that plug straight into the mains. These can be:

Clunky: They take up loads of room on a power strip
Fragile: If they break, finding a matching replacement can be tricky
Less roadworthy: Smaller jacks and connectors are more prone to damage

Expensive Power Supplies:

What You're Paying For

Premium power supplies may cost more, but they’re built for tone, safety, and reliability. Here’s what you get:

✅ Isolated Outputs

Each pedal gets its own clean power source—no shared noise or ground loops.

✅ High Current Outputs

Plenty of juice for power-hungry digital pedals, loopers, and MIDI devices.

✅ Multiple Voltages

Switchable outputs for 9V, 12V, and 18V—perfect for more complex setups.

✅ Polarity Protection

Some supplies include built-in safety features or adapter cables for centre-positive pedals.

✅ Quiet, Consistent Power

No buzz, hum, or interference. Just clean, stable tone.

✅ Built to Last

Pro-grade enclosures, cables, and connections that won’t let you down on stage.

⚡ Standard IEC (“Kettle Lead”) Power Cables

Instead of a wall wart, many high-end supplies use a standard IEC cable—the same type used for amps and PA gear. The benefits:

Easy to replace: Any venue or studio will have one
Sturdy: Less prone to wear and damage
Tidy cabling: No awkward brick under your board
Tour-ready: Some have 100–240V auto-switching for international use

🔌 Power Supply Cables:

What They Are and How to Use Them

Buying a power supply is only half the battle—you also need the right cables to connect it to your pedals. Most power supplies come with a variety of power cables, and each has a specific use.

Here’s a quick guide:

1. Standard Barrel Cables (2.1mm, Centre-Negative)

🟢 Most Common Type

Used for most modern pedals (Boss, MXR, EHX, etc.)
Usually included in the box
Connect one power output to one pedal

Use for: Any pedal with a standard 9V DC input

2. Daisy Chain Cables

🔗 One plug into the power supply, multiple plugs to pedals
Often included with both budget and premium power supplies
Not isolated — pedals share the same ground and power line
Any noise from one pedal can affect the others

✅ Use only when: All pedals are analog or low-noise Pedals are known to play well together (no interference or hum) You’ve tested your setup and it sounds clean

⚠️ Avoid if: You use digital pedals, reverb/delay, or anything with a processor You notice hum, buzz, or high-frequency whine You’re combining analog and digital pedals

3. Polarity Inverter Cables

🔁 Reverses the polarity of the plug
Turns a centre-negative output into a centre-positive (or vice versa)

Use for: Pedals that require centre-positive power (e.g. some vintage or boutique pedals)

Warning: Double-check your pedal’s requirements—using the wrong polarity can damage your gear

4. Barrel Size Adapters (2.5mm, 3.5mm, etc.)

Adapts standard 2.1mm plugs to less common sizes
Some pedals (e.g. Line 6, some vintage units) use larger/smaller jacks

Use for: Pedals with non-standard power jacks

5. Voltage Doublers / Current Doublers

Special Y-cables that combine outputs for higher voltage or current
Voltage doubler: Combines two 9V outputs to make 18V
Current doubler: Combines current from two outputs for high-demand pedals

Use only if: Your power supply and the pedal manufacturer explicitly support it

How to Choose the Right Power Supply

Feeling overwhelmed? Here's a simple step-by-step guide:

1. Count Your Pedals

1–3 analog pedals? A basic daisy chain might work.
4+ pedals or digital effects? Go isolated.

2. Check Voltage Needs

Most pedals use 9V, but some require 12V or 18V.
A good supply will have adjustable outputs.

3. Add Up Current Draw

Each pedal has a milliamp (mA) requirement. Add them up.
Choose a supply where each output can meet or exceed the pedal’s draw.

4. Check Polarity

Most are centre-negative, but always check. Use polarity adapters if needed.

5. Plan for Expansion

Choose a supply with extra outputs or a brand that offers expansion units.

6. Stick With Trusted Brands

Look for names like Voodoo Lab, Cioks, Strymon, MXR, and Truetone.

⚖️ What If a Pedal Says “9V–18V”?

Some pedals are designed to run on a range of voltages, most commonly 9V to 18V. So which should you use?

🔌 Running at 9V

✅ Standard voltage
✅ Often adds a little natural compression or “sag”
✅ Draws more current than 18V for the same power usage, but 9V outputs usually offer higher current capacity on most power supplies

Best for: Overdrives, fuzz, and vintage-style effects where a bit of softness or saturation is part of the character.

⚡ Running at 18V

✅ More headroom—less chance of signal clipping
✅ Tighter response, more clarity, and better dynamics
✅ Draws less current, but 18V outputs may be more limited on some supplies

Best for: Clean boosts, preamps, or pedals used with high-output pickups or in effects loops where clean signal is key.

❗ Important Notes:

Only use 18V if the pedal is rated for it—always check the label or manual
Make sure your supply has enough current available at that voltage
Try both if you're curious—the difference can be subtle or dramatic, depending on the pedal

🔧 Troubleshooting: How to Diagnose Noise in Your Pedalboard

If you're hearing hum, buzz, or interference, try this step-by-step process:

1. Power Supply Setup

Are all digital pedals on isolated outputs?
Is the current draw within limits?
Avoid daisy-chaining high-draw or sensitive pedals

2. Swap Cables and Isolate

Use fresh patch and power cables
Connect one pedal at a time to find the noisy one

3. Identify the Noise

Hum: Often a ground loop
Buzz or whine: Common with digital interference
Hiss: Possibly a bad cable or gain mismatch

4. Check Voltage & Polarity

Wrong voltage = malfunction or noise
Wrong polarity = possible damage

5. Lift the Ground (Safely)

Use ground lift options on DI boxes or isolated power supplies
Never lift mains ground pins

6. Try a New Power Circuit

Electrical noise can come from lights, dimmers, or poor house wiring
Try another room or use a power conditioner

7. Use Buffers or Isolators

Impedance mismatch can cause tone loss or noise
A good buffer helps with long cable runs and passive pedals

Final Thoughts

If you’re just getting started with a couple of analog pedals, a cheap supply may get the job done—for now. But if you’re using digital effects, daisy-chaining more than 3–4 pedals, or playing live, a high-quality, isolated power supply is one of the best upgrades you can make.

At Cosmic Loop FX, we believe great tone starts with a clean signal path—and your power supply is the foundation. Don’t let a noisy or underpowered setup hold you back.