just brew it! wrote:Not necessarily. High impedance headphones typically require higher voltage but lower current to produce a given sound level. Disregarding differences in headphone efficiency, sound level roughly correlates with power input, which is voltage x current. High voltage and low current, *or* low voltage and high current can both give you the same amount of power delivered to the load.
Implying that the output changes the voltage level depending on the load. If the source is changing its output voltage to drive the headphones (therefore delivering the same power), I would agree, but given the same voltage input, you will draw less power with higher impedance headphones.
If the noise is due to EMI-induced voltage spikes in the motherboard traces or case wiring then high impedance headphones could very well be more sensitive to it, not less.
Again, given the same voltage, more power will be delivered to the lower impedance headphones because they have less resistance to the resulting current.
Now when I think about this more, using "impedance" the way we are is a little sloppy. Impedance includes resistance, which is the only component that directly affects real power. However, it also includes inductance and capacitance, which have different responses to different frequencies.
If the higher impedance headphones are more
inductive, they would react more to quick voltage spikes, and I would agree that they would be more sensitive to this noise. However, the input impedance from the specifications does not give us this inductive factor. And even then, there are electrical ways to handle voltage spikes, and the physical materials will also play a role in dampening such spikes.
Really, in order to make statements about how these EMI voltage spikes would affect the headphones, I think we need the impulse response or a step response, which is not given in either of the measurements we have (impedance and sensitivity).
You're confusing EMI with the general concept of "white" noise. They're not the same thing. The noise induced by EMI from other components isn't going to be white noise, it is going to have sharp peaks and dips at various frequencies, related to the switching speeds of the various digital circuits and voltage regulators.
Point. The OP described the noise as "static" which I immediately replaced with "white noise."
On second thought, let's not go to TechReport. It's infested by crypto bull****.