hi Adam,
yes, impedance matters more if you are using Transparent cables. impedance will affect the frequency response curve. However, given the impedance difference between your EMM labs and Wadia DAC is very small, i doubt the extra re-certification worth it. If you have another tube DAC, then the "rework" on the cable will be necessary as it will give a noticeable impact on the sound even if the impedance difference is small.
Usually for output impedance, it should be 20x lower than the input impedance of the connecting equipment.
yes, impedance matters more if you are using Transparent cables. impedance will affect the frequency response curve. However, given the impedance difference between your EMM labs and Wadia DAC is very small, i doubt the extra re-certification worth it. If you have another tube DAC, then the "rework" on the cable will be necessary as it will give a noticeable impact on the sound even if the impedance difference is small.
Usually for output impedance, it should be 20x lower than the input impedance of the connecting equipment.