From my own rack: Abyss 1266 TC
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Get the amplifier answer in milliwatts and volts — worked out from published figures, not from a reviewer’s impression.
How many milliwatts and volts your headphones need at any listening level, from the published specs.
Every source judged on power, output impedance and hiss at once — the three ways a source goes wrong.
Will a source hiss with sensitive in-ears? The half of amp matching almost nobody calculates.
Check a source against the one-eighth rule before it starts shaping the sound of your in-ears.
dB/mW or dB/V? Get both, and see why the difference wrecks most online calculators.
The most common headphone output in the world was designed around studio headphones. What that means for yours.
| Model | Impedance | Power for 100 dB | Voltage | Sources that drive it |
|---|---|---|---|---|
| Sennheiser HD 600 | 300 Ω | 6.6 mW | 1.41 V | 225 of 280 |
| Sennheiser HD 650 | 300 Ω | 1.7 mW | 0.71 V | 271 of 280 |
| HiFiMAN Edition XS | 18 Ω | 6.3 mW | 0.34 V | 274 of 280 |
| Beyerdynamic DT 770 Pro (80Ω) | 80 Ω | 2.5 mW | 0.45 V | 280 of 280 |
| Audio-Technica ATH-M50X | 38 Ω | 1.3 mW | 0.22 V | 280 of 280 |
| HiFiMAN Sundara | 32 Ω | 6.3 mW | 0.45 V | 279 of 280 |
| Sony MDR-7506 | 63 Ω | 0.25 mW | 0.13 V | 280 of 280 |
| Beyerdynamic DT 990 Pro (250Ω) | 250 Ω | 2.5 mW | 0.79 V | 267 of 280 |
| Focal Clear MG | 55 Ω | 0.40 mW | 0.15 V | 280 of 280 |
| Moondrop Blessing 3 | 14.8 Ω | 0.68 mW | 0.10 V | 280 of 280 |
| HiFiMAN Susvara | 60 Ω | 50 mW | 1.73 V | 173 of 280 |
“Drive it” means at least 3 dB of headroom at 100 dB SPL. Each model’s page names the document its figures came from.
Per milliwatt or per volt — the two conventions sit up to 21.0 dB apart, and the spec sheet does not say which one it means. It is not one sloppy manufacturer.
Every one of the 567 models here, plotted by impedance against the power it actually needs. If the folklore were right, the cloud would slope upwards. It does not slope at all. The whole argument, with the numbers.
Most come straight from the manufacturer’s own spec sheet, and each page names the document. Where a figure comes from a shop listing or an independent measurement instead, the page says so — and where the maker prints nothing at all, it says that too, instead of guessing.
Some makers quote sensitivity per volt, others per milliwatt, and many never say which. Everything here is converted to one unit where the maker states it, and the conversion is shown.
This site rates nothing by ear. It is arithmetic on published figures — which is exactly what most spec sheets never do for you.