USB to 9VDC Adapter for Korg Volca Series

The Korg Volca series includes 10 different analog and digital synthesiser in a compact and affordable format, that has been widely adopted by new and experienced musicians. Though they can be used with batteries, when you want to use them with a power supply you face the problem that they are not compatible with the standard for guitar effect pedals. Not only the plug is different but also the polarity!

Recently, I discovered that lots of internet modems now come with a USB to 9VDC adapter instead of the wall plug and I thought that it would be amazing to use for guitar pedals. After receiving the USB adapter from a chinesse website I tested the polarity and it was reversed than the standar guitar pedal, so I needed to rewire the cable inside the USB adapter.

The materials that you need to buy are easily available in chinesse e-commerce sites for less than 5€ and are basically an USB to 9VDC adapter (around 3€) and the connector for the Volca which is a little bit special. The connector is a 4.75 mm x 1.7 mm (EIAJ-03/EIAJ-III) barrel plug (around 0,5€)

Regarding tools, you will just need a soldering iron and a multimeter.

First thing is to check the polarity of the USB adapter with a multimeter to make sure that the black and red wires are the negative and positive.

Make sure that the black goes to negative and the red to positive and you will not have any problem.