Both are portable players, $1799 against $1999. This page puts them side by side on the only three things a maker can be held to — power, output impedance and noise — and then asks the question that actually matters: which headphones do they treat differently?
The FiiO M17 reaches 100 dB on 567 of the 567 models here, the HiBy R8 II on 565.
| Specification | FiiO M17 | HiBy R8 II |
|---|---|---|
| Power into 32Ω | 500 mW | 225 mW |
| Power into 150Ω | 115 mW | 48 mW |
| Power into 300Ω | 63 mW | 24 mW |
| Power into 600Ω | 32 mW | 12 mW |
| Output impedance | 1 Ω | 1 Ω |
| Output noise | 3.5 µV | 3.2 µV |
| Price | $1799 | $1999 |
| Headphones it reaches 100 dB on out of 567 | 567 | 565 |
A figure marked not published is missing from the maker’s own material, which is not the same as being good or bad. Where one of these two publishes a number and the other does not, the comparison on that axis cannot be made at all — and saying so is more useful than guessing.
2 headphones reach 100 dB on the FiiO M17 but not on the HiBy R8 II — Moondrop PARA, Symphonium Titan.
4 headphones stay below the audible-hiss threshold on the HiBy R8 II but cross it on the FiiO M17 (Audio-Technica ATH-CKS1100, EPZ K5, Grado Signature S750, 1 more).
565 of the 567 models here reach 100 dB on both. That is a power count and nothing more; whether either source suits a given headphone also depends on the two lines above.
Each has a page of its own with every power figure traced to what the maker published and a full headphone list: FiiO M17 and HiBy R8 II. Or put either against your own headphones in the source comparison tool.