Edition XS vs HE-6se V2: which needs more amplifier?

The HiFiMAN Edition XS is 18Ω at 92.0 dB (no reference unit printed); the HiFiMAN HE-6se V2 is 50Ω at 83.5 dB (no reference unit printed). 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 HE-6se V2 needs 8.5 dB more than the Edition XS to reach the same loudness — 45 mW against 6.3 mW.

The numbers that decide it

SpecificationEdition XSHE-6se V2
Impedance18 Ω50 Ω
Sensitivity92.0 dB83.5 dB
Sensitivity (voltage)109.4 dB/V96.5 dB/V
Power for 100 dB6.3 mW45 mW
Voltage for 100 dB0.34 V1.49 V
Current for 100 dB18.7 mA29.9 mA
Highest source impedance
that leaves them alone (one-eighth rule)
2.25 Ω6.25 Ω
Sources that reach 100 dB
out of 280
280240

One caution before reading the rows. HiFiMAN Edition XS and HiFiMAN HE-6se V2 printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, each of them needs far more than the table says. Why the two readings differ by so much.

Where the two part company

40 of the 280 sources have the power for the Edition XS but not for the HE-6se V2 — Apple USB-C dongle (US), Apple USB-C dongle (EU), Generic CX31993 dongles, 37 more.

1 source is low enough in output impedance for the HE-6se V2 under the one-eighth rule but not for the Edition XS (Shanling H5).

240 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: HiFiMAN Edition XS and HiFiMAN HE-6se V2. Each figure on this page is labelled on those pages with where it came from, including the ones HiFiMAN never published — what that maker publishes, counted.