A Bolt from the… purple actually.

Introduction – What Is the Bolt DAC/Amp?

The HELM Audio Bolt is an ultra portable DAC and headphone amp designed with a view to being connected directly to mobile devices and simultaneously solving their lack of headphone output and improving the quality available at the same time. Absolutely key to this is the ‘ultra portable’ phrase. You can connect your phone to any USB DAC and, if that DAC has a battery (or even on occasions when it doesn’t like the iFi ZEN DAC), it can be used on the move.
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