The Truthear Hola is 28Ω at 104.5 dB/mW; the Truthear PURE is 13.8Ω at 105.4 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 Hola needs 0.9 dB more than the PURE to reach the same loudness — 0.35 mW against 0.29 mW.
| Specification | Hola | PURE |
|---|---|---|
| Impedance | 28 Ω | 13.8 Ω |
| Sensitivity | 104.5 dB/mW | 105.4 dB/mW |
| Sensitivity (voltage) | 120.0 dB/V | 124.0 dB/V |
| Power for 100 dB | 0.35 mW | 0.29 mW |
| Voltage for 100 dB | 100 mV | 63 mV |
| Current for 100 dB | 3.6 mA | 4.6 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 3.50 Ω | 1.73 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.
4 sources are low enough in output impedance for the Hola under the one-eighth rule but not for the PURE (Schiit Vali 2+, Astell&Kern HC3, RME Fireface UFX II, 1 more).
4 sources stay below the audible-hiss threshold with the Hola but cross it with the PURE (FiiO BTR11, FiiO K11 R2R, Lake People G111 Mk II, 1 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: Truthear Hola and Truthear PURE. Every figure on this page comes from what Truthear published, or is derived from it — what that maker publishes, counted.