MyVolts USB Cable Powers Anything 9V For Hours - Like Volcas
All you need is a battery, laptop or USB charger 19/05/16
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The folks over at myVolts have been working on portable USB power solutions for some time, they have a cable which can upscale your 5V USB power source to a 9V one. One of their uses being a way to power Korg Volcas or busking amps.
They also have a splitter to 5 way Volca tails, so one battery pack and that will have your Volca collection working without the need to buy expensive individual power supplies or multiple AA batteries.
Over on Kickstarter they have a project for another nicely designed cable the RipCord which, when combined with adapters lets you power Volcas, guitar pedals and many other items.
Project ends June 6th 2016 - and starts at €12 for the cable.