Regarding headphone ohms and sensitivity in regards to amplification. 2020-03-05 17:56:19 I’m wondering if anyone could answer a question that I can’t seem to find a solid answer for. I own a pair of Sennheiser HD600 headphones that I sometimes like to use with my iPhone and lightning dongle. The headphones are 300 Ohms, but they’re also pretty efficient. I can achieve a loud enough listening volume with this setup, though my MacBook has a louder output. I’m under the impression that if a loudspeaker or headphones are loud enough, than the amplification is doing its job and no more thought needs to be given to it. What I’m not clear about is the fact that, while these headphones are rated at 300 ohms, there are parts of the frequency range that are actually up to 600 ohms. Does this mean that having insufficient power could adequately power parts of the frequency range but not other parts and change the frequency response?