This is the section of the headphone amp of DX5
Signal amp is using TI OPA1612A Driver is using Ti TPA6120
Gain is switch using relay which is good
According to the datasheet of the Ti TPA6120 the resistor on the output should at least be 10ohm
But topping choose instead to go with 3.3 ohm, So it might not be a good idea to pair it with a headphone with ultra low impendence,
With a resistor if 3.3ohm in series with the output how could they specify the output impendence to be <0.1ohm ?
The rated power from the datasheet of TPA 6120 is 80mW into 600ohm From a ±12-V Supply at 0.00014% THD + N
Anybody knows what NFCA means ? I did not find any global feedback from the output
View attachment 218937