The Audeze LCD-X 2021 is 20Ω at 103.0 dB/mW; the Dan Clark Audio Expanse is 26Ω at 90.0 dB/mW. 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 Dan Clark Audio Expanse needs 13.0 dB more than the Audeze LCD-X 2021 to reach the same loudness — 10 mW against 0.50 mW.
| Specification | Audeze LCD-X 2021 | Dan Clark Audio Expanse |
|---|---|---|
| Impedance | 20 Ω | 26 Ω |
| Sensitivity | 103.0 dB/mW | 90.0 dB/mW |
| Sensitivity (voltage) | 120.0 dB/V | 105.9 dB/V |
| Power for 100 dB | 0.50 mW | 10 mW |
| Voltage for 100 dB | 0.10 V | 0.51 V |
| Current for 100 dB | 5.0 mA | 19.6 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.50 Ω | 3.25 Ω |
| Sources that reach 100 dB out of 280 | 280 | 279 |
1 of the 280 sources has the power for the Audeze LCD-X 2021 but not for the Dan Clark Audio Expanse — Steinberg UR22C.
279 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: Audeze LCD-X 2021 and Dan Clark Audio Expanse. Every figure on this page comes from what Audeze and Dan Clark Audio published, or is derived from it — what Audeze publishes and what Dan Clark Audio publishes, both counted.