Powering an HX Stomp from a pedalboard supply

Run the HX Stomp from the DC-3 supply Line 6 ships with it, and run everything else from your brick. Line 6 specifies 9 V DC center-negative at 3 A. No standard isolated pedalboard output supplies 3 A — the most generous common brick gives 500 mA per output, which is one sixth of it. There is no cable, splitter or adaptor that fixes this.

This is the most common power mistake on modern pedalboards, and it is common precisely because it half works. The unit boots. It passes signal. Then it reboots mid-set, or the display glitches, or it behaves differently once it warms up — symptoms that look like a faulty unit and are actually a supply that cannot deliver.

01Step 1 — the published figures

There is no premium brick further down the list that solves it. The gap between 500 mA and 3 A is not a matter of spending more — it is a different class of supply, and the correct one is already in the box.

02Step 2 — why doubler cables do not help

A current-doubler cable combines two outputs into one and sums their current at the same voltage. Two 500 mA outputs give you 1,000 mA. That is a real and useful trick for a pedal that needs 600 or 700 mA.

It does not get you to 3 A. You would need six 500 mA outputs combined, which no doubler cable does, and which would leave nothing for the rest of the board. The arithmetic closes the option rather than the manufacturer closing it.

04Step 3 — plan the rest of the board around the Stomp

Once the Stomp is on its own supply, the brick only has to cover the pedals around it. That is usually a tuner, a drive or two and possibly a wah — a total well inside any isolated supply on this page.

Worked example. A TU-3 at 20 mA, an SD-1 at 10 mA, a BD-2 at 20 mA and a TR-2 at 25 mA is 75 mA in total. Add 30% headroom and you need about 98 mA, so a single 100 mA output would technically cover the whole group through a daisy chain, and any of the isolated bricks above covers it several times over. The Stomp was never the problem for the brick; the brick was never the answer for the Stomp.

05Step 4 — the two physical details that also catch people

1. Polarity. Line 6 publishes 9 V DC center-negative for the HX Stomp, which is the standard for guitar pedals and the opposite of most consumer electronics. A center-positive supply of the right voltage and current will still not work.
2. The plug itself. The DC-3 is a barrel connector like any other, so it fits a daisy-chain cable perfectly and gives you no warning that the supply behind it cannot deliver. Nothing about the connector tells you the rating — only the label does.

06What this means for board layout

Two supplies means two mains sockets, two wall-wart or IEC footprints, and a second thing to fasten underneath. Plan for it before you buy the board rather than after — a Pedaltrain Nano+ has nowhere to hide two supplies.

Best pedalboards covers the sizes, and best power supplies covers the bricks in full. The general arithmetic — how to add draws, and why 30% headroom — is in power requirements explained.