The Dunu SA6 MKII is 24Ω at 114.0 dB (no reference unit printed); the Dunu Vulkan is 15Ω at 109.0 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 Vulkan needs 5.0 dB more than the SA6 MKII to reach the same loudness — 0.13 mW against 0.04 mW.
| Specification | SA6 MKII | Vulkan |
|---|---|---|
| Impedance | 24 Ω | 15 Ω |
| Sensitivity | 114.0 dB | 109.0 dB |
| Sensitivity (voltage) | 130.2 dB/V | 127.2 dB/V |
| Power for 100 dB | 0.04 mW | 0.13 mW |
| Voltage for 100 dB | 31 mV | 43 mV |
| Current for 100 dB | 1.3 mA | 2.9 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 3.00 Ω | 1.88 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. Dunu SA6 MKII and Dunu Vulkan 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.
Every source in the database that drives one of them drives the other. On power, the choice between these two changes nothing about what amplifier you need.
3 sources are low enough in output impedance for the SA6 MKII under the one-eighth rule but not for the Vulkan (Astell&Kern HC3, RME Fireface UFX II, RME Fireface UFX III).
7 sources stay below the audible-hiss threshold with the Vulkan but cross it with the SA6 MKII (FiiO K7, FiiO Q15, FiiO M15S, 4 more).
280 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: Dunu SA6 MKII and Dunu Vulkan. Each figure on this page is labelled on those pages with where it came from, including the ones Dunu never published — what that maker publishes, counted.