The Symphonium Helios is 8.5Ω at 83.3 dB/mW; the Symphonium Triton is 8.3Ω at 86.2 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 Helios needs 2.9 dB more than the Triton to reach the same loudness — 47 mW against 24 mW.
| Specification | Helios | Triton |
|---|---|---|
| Impedance | 8.5 Ω | 8.3 Ω |
| Sensitivity | 83.3 dB/mW | 86.2 dB/mW |
| Sensitivity (voltage) | 104.0 dB/V | 107.0 dB/V |
| Power for 100 dB | 47 mW | 24 mW |
| Voltage for 100 dB | 0.63 V | 0.45 V |
| Current for 100 dB | 74.2 mA | 53.8 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 1.06 Ω | 1.04 Ω |
| Sources that reach 100 dB out of 280 | 179 | 229 |
50 of the 280 sources have the power for the Triton but not for the Helios — FiiO SnowSky Tiny B, Tanchjim Stargate II, Fosi Audio N3, 47 more.
179 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: Symphonium Helios and Symphonium Triton. Every figure on this page comes from what Symphonium published, or is derived from it — what that maker publishes, counted.