“Hard to drive” is usually said about high-impedance headphones, and that is the wrong half of the specification. What decides how much power a headphone needs is sensitivity; impedance decides whether that power arrives as volts or as current. The models at the top of this list are mostly low-impedance planars, and several of them need more power than a 300 Ω Sennheiser does.
Every row is the power needed for 100 dB SPL, calculated from the model’s own published sensitivity, with a count of how many of the 280 sources in this database deliver that much into its impedance.
One thing to read this list with. Every position on it is calculated from sensitivity, and 175 of these 567 models have a sensitivity figure whose reference unit the maker never printed. The number is read as per milliwatt here, because that is the commoner convention on a spec sheet that omits the unit — but if one of them meant per volt, that model is less sensitive than this list assumes, and by how much depends on its impedance: from 2.2 dB at 600Ω to 21.0 dB at 8Ω across the ones affected here. Each model page says which case it is in and shows both readings. A list that does not mention this is not more accurate than this one; it is only quieter about the same problem.
| Headphone | Impedance | Sensitivity | Needs for 100 dB | Sources here that reach it |
|---|---|---|---|---|
| Symphonium Titan | 3 Ω | 79.8 dB/mW | 105 mW | 85 of 280 |
| Moondrop PARA | 8 Ω | 80.0 dB/mW | 100 mW | 130 of 280 |
| Moondrop COSMO | 15 Ω | 81.8 dB/mW | 66 mW | 188 of 280 |
| Moondrop VENUS | 18 Ω | 82.6 dB/mW | 55 mW | 225 of 280 |
| HiFiMAN Susvara | 60 Ω | 83.0 dB/mW | 50 mW | 231 of 280 |
| Symphonium Helios | 8.5 Ω | 83.3 dB/mW | 47 mW | 179 of 280 |
| HiFiMAN HE-6se V2 | 50 Ω | 83.5 dB/mW | 45 mW | 240 of 280 |
| HiFiMAN HE6 Remastered | 50 Ω | 83.5 dB/mW | 45 mW | 240 of 280 |
| Moondrop SKYLAND | 60 Ω | 83.8 dB/mW | 42 mW | 235 of 280 |
| Symphonium Crimson | 6.05 Ω | 83.8 dB/mW | 42 mW | 166 of 280 |
| Moondrop PARA 2 | 9 Ω | 85.5 dB/mW | 28 mW | 223 of 280 |
| Symphonium Zenith | 6.1 Ω | 85.9 dB/mW | 26 mW | 197 of 280 |
| HiFiMAN Susvara Unveiled | 45 Ω | 86.0 dB/mW | 25 mW | 259 of 280 |
| Symphonium Triton | 8.3 Ω | 86.2 dB/mW | 24 mW | 229 of 280 |
| Thieaudio Hype 10 | 18 Ω | 87.6 dB/mW | 17 mW | 264 of 280 |
The table shows the first 15 of 567. The rest are in the full headphone database, where every figure is labelled with where it came from.
11 of the 578 headphones in this database are not on this list because they are electrostatics. They run from an energiser at a couple of hundred volts rather than from an amplifier, so the milliwatt figure this list sorts by does not describe anything real about them and is not calculated for them anywhere on this site.
This is not a ranking of sound quality and cannot be. It sorts one number that manufacturers printed, and manufacturers do not print anything about how their products sound. Every row links to that product’s own page, where each figure is labelled with the document it came from.
Quietest sources for sensitive in-ears · Lowest published output impedance · Most power into 300 Ω · Sources that drive everything here · Audio interfaces as headphone amplifiers · Sources under $100 · Most sensitive in-ears · Quietest desktop sources · What balanced actually gains · Portable players by power · Most power per dollar · High-impedance headphones