The 64 Audio U12t is 12.6Ω at 108.0 dB/mW; the Campfire Audio Andromeda 2020 is 9Ω at 94.0 dB (no figure from the maker at all). 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 Campfire Audio Andromeda 2020 needs 14.0 dB more than the 64 Audio U12t to reach the same loudness — 4.0 mW against 0.16 mW.
| Specification | 64 Audio U12t | Campfire Audio Andromeda 2020 |
|---|---|---|
| Impedance | 12.6 Ω | 9 Ω |
| Sensitivity | 108.0 dB/mW | 94.0 dB |
| Sensitivity (voltage) | 127.0 dB/V | 114.5 dB/V |
| Power for 100 dB | 0.16 mW | 4.0 mW |
| Voltage for 100 dB | 45 mV | 0.19 V |
| Current for 100 dB | 3.5 mA | 21.0 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 1.57 Ω | 1.12 Ω |
| Sources that reach 100 dB out of 280 | 280 | 279 |
One caution before reading the rows. For Campfire Audio Andromeda 2020 the maker publishes no sensitivity figure at all. The number in the table was collected when this database was first built and has never been traced to a manufacturer document, so treat every row below it as an estimate rather than a specification.
1 of the 280 sources has the power for the 64 Audio U12t but not for the Campfire Audio Andromeda 2020 — Steinberg UR22C.
6 sources are low enough in output impedance for the 64 Audio U12t under the one-eighth rule but not for the Campfire Audio Andromeda 2020 (FiiO K11, FiiO BTR7, FiiO M11S, 3 more).
15 sources stay below the audible-hiss threshold with the Campfire Audio Andromeda 2020 but cross it with the 64 Audio U12t (FiiO BTR11, FiiO K11 R2R, Lake People G103-S Mk II, 12 more).
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: 64 Audio U12t and Campfire Audio Andromeda 2020. Each figure on this page is labelled on those pages with where it came from, including the ones 64 Audio and Campfire Audio never published — what 64 Audio publishes and what Campfire Audio publishes, both counted.