- Sep 7, 2008
What makes one headphone harder to drive than another headphone? I would imagine that lower impedance headphones are harder to drive because they draw more current (P=I^2*R) for the same output power and the am might be current limited. Alternatively I can see that high impedance headphones could be harder to drive because (P=V^2/R) and they require higher voltage for the same output power, possibly the amp cannot provide high enough voltages and limits. And finally it could just turn out that most amps have either high or low output impedances and therefore get maximum power transfer whenever the phones are impedance matched. Which of these scenarios are the true dominating factor? Are high impedance headphones harder or easier to drive?