The SW1X DAC I Standard version is now available with two different I/V conversion techniques: Active or Passive. While the active current to voltage (I/V) conversion via a single specially selected transistor matches the impedance better between DAC current out and the valve grid, passive conversion via a resistor provides an alternative solution with a different sound signature.

Difference in sound between Passive and Active I/V (current to voltage) conversion

There are distinct difference in sound between those conversion techniques, implemented in Active and Passive versions of SW1X DAC I. While the sound of active I/V over a specially selected transistor has a better “dynamic bite”, the passive resistor I/V method gives a more relaxed feeling to the sound. On the one hand, Active I/V of DAC I has an edge over Passive I/V in resolving details, on the other, passive I/V provides a more organic envelope to the texture of music. Both conversion techniques have merits with a particular music in mind: Active I/V version will particularly excel with energized Rock or Electronic type of music while Passive I/V will sound more harmonically with Jazzy or Classical type of music.

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