The HiFiMAN Edition XV is 12Ω at 92.0 dB (no reference unit printed); the Meze Empyrean is 32Ω at 100.0 dB (no figure from the maker at all). This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.
The HiFiMAN Edition XV needs 8.0 dB more than the Meze Empyrean to reach the same loudness — 6.3 mW against 1.0 mW.
| Specification | HiFiMAN Edition XV | Meze Empyrean |
|---|---|---|
| Impedance | 12 Ω | 32 Ω |
| Sensitivity | 92.0 dB | 100.0 dB |
| Sensitivity (voltage) | 111.2 dB/V | 114.9 dB/V |
| Power for 100 dB | 6.3 mW | 1.0 mW |
| Voltage for 100 dB | 0.28 V | 0.18 V |
| Current for 100 dB | 22.9 mA | 5.6 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 1.50 Ω | 4.00 Ω |
| Sources that reach 100 dB out of 280 | 278 | 280 |
One caution before reading the rows. HiFiMAN Edition XV printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, that model needs far more than the table says. Why the two readings differ by so much. For Meze Empyrean the maker publishes no sensitivity figure at all. The number in the table was collected when this database was first built and has never been traced to a manufacturer document, so treat every row below it as an estimate rather than a specification.
2 of the 280 sources have the power for the Meze Empyrean but not for the HiFiMAN Edition XV — Apple USB-C dongle (EU), Steinberg UR22C.
5 sources are low enough in output impedance for the Meze Empyrean under the one-eighth rule but not for the HiFiMAN Edition XV (FiiO KA13, Schiit Vali 2+, Astell&Kern HC3, 2 more).
278 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: HiFiMAN Edition XV and Meze Empyrean. Each figure on this page is labelled on those pages with where it came from, including the ones HiFiMAN and Meze never published — what HiFiMAN publishes and what Meze publishes, both counted.