Audeze LCD-5 vs ZMF Atrium: which needs more amplifier?

The Audeze LCD-5 is 14Ω at 90.0 dB/mW; the ZMF Atrium is 300Ω at 96.0 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 Audeze LCD-5 needs 6.0 dB more than the ZMF Atrium to reach the same loudness — 10 mW against 2.5 mW.

The numbers that decide it

SpecificationAudeze LCD-5ZMF Atrium
Impedance14 Ω300 Ω
Sensitivity90.0 dB/mW96.0 dB/mW
Sensitivity (voltage)108.5 dB/V101.2 dB/V
Power for 100 dB10 mW2.5 mW
Voltage for 100 dB0.37 V0.87 V
Current for 100 dB26.7 mA2.9 mA
Highest source impedance
that leaves them alone (one-eighth rule)
1.75 Ω37.50 Ω
Sources that reach 100 dB
out of 280
274277

Where the two part company

1 of the 280 sources has the power for the Audeze LCD-5 but not for the ZMF Atrium — Sony NW-A306.

4 of the 280 sources have the power for the ZMF Atrium but not for the Audeze LCD-5 — Zoom AMS-22, Tascam US-2x2HR, Roland Rubix22, 1 more.

24 sources are low enough in output impedance for the ZMF Atrium under the one-eighth rule but not for the Audeze LCD-5 (Zoom AMS-22, Arturia MiniFuse 2, Arturia MiniFuse 1, 21 more).

273 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.

Both pages in full

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-5 and ZMF Atrium. Every figure on this page comes from what Audeze and ZMF published, or is derived from it — what Audeze publishes and what ZMF publishes, both counted.