The HiFiMAN HE6 Remastered is 50Ω at 83.5 dB (no reference unit printed); the HiFiMAN Susvara Unveiled is 45Ω at 86.0 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 HE6 Remastered needs 2.5 dB more than the Susvara Unveiled to reach the same loudness — 45 mW against 25 mW.
| Specification | HE6 Remastered | Susvara Unveiled |
|---|---|---|
| Impedance | 50 Ω | 45 Ω |
| Sensitivity | 83.5 dB | 86.0 dB |
| Sensitivity (voltage) | 96.5 dB/V | 99.5 dB/V |
| Power for 100 dB | 45 mW | 25 mW |
| Voltage for 100 dB | 1.49 V | 1.06 V |
| Current for 100 dB | 29.9 mA | 23.6 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 6.25 Ω | 5.62 Ω |
| Sources that reach 100 dB out of 280 | 240 | 259 |
One caution before reading the rows. HiFiMAN HE6 Remastered and HiFiMAN Susvara Unveiled 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.
19 of the 280 sources have the power for the Susvara Unveiled but not for the HE6 Remastered — Generic CX31993 dongles, Kiwi Ears Allegro Pro, ddHiFi TC35Pro (Mountain2), 16 more.
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.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: HiFiMAN HE6 Remastered and HiFiMAN Susvara Unveiled. 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.