The Campfire Audio Astrolith is 8.2Ω at 100.1 dB/mW; the Campfire Audio Chimera is 5.5Ω at 108.1 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 Astrolith needs 8.0 dB more than the Chimera to reach the same loudness — 0.98 mW against 0.15 mW.
| Specification | Astrolith | Chimera |
|---|---|---|
| Impedance | 8.2 Ω | 5.5 Ω |
| Sensitivity | 100.1 dB/mW | 108.1 dB/mW |
| Sensitivity (voltage) | 121.0 dB/V | 130.7 dB/V |
| Power for 100 dB | 0.98 mW | 0.15 mW |
| Voltage for 100 dB | 90 mV | 29 mV |
| Current for 100 dB | 10.9 mA | 5.3 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 1.02 Ω | 0.69 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
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.
42 sources are low enough in output impedance for the Astrolith under the one-eighth rule but not for the Chimera (FiiO SnowSky Tiny B, FiiO KA11, JDS Labs Atom+ (2nd gen), 39 more).
25 sources stay below the audible-hiss threshold with the Astrolith but cross it with the Chimera (Kiwi Ears Allegro Mini, FiiO BTR11, FiiO K11 R2R, 22 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: Campfire Audio Astrolith and Campfire Audio Chimera. Every figure on this page comes from what Campfire Audio published, or is derived from it — what that maker publishes, counted.