Both are portable players, $499 against $1799. 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 FiiO M11S on 566.
| Specification | FiiO M11S | FiiO M17 |
|---|---|---|
| Power into 32Ω | 200 mW | 500 mW |
| Power into 150Ω | 44 mW | 115 mW |
| Power into 300Ω | 23 mW | 63 mW |
| Power into 600Ω | 12 mW | 32 mW |
| Output impedance | 1.5 Ω | 1 Ω |
| Output noise | 1.8 µV | 3.5 µV |
| Price | $499 | $1799 |
| Headphones it reaches 100 dB on out of 567 | 566 | 567 |
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.
1 headphone reaches 100 dB on the FiiO M17 but not on the FiiO M11S — Symphonium Titan.
36 headphones are left alone by the FiiO M17 under the one-eighth rule but coloured by the FiiO M11S (64 Audio Aspire 1, 64 Audio Fourte, 64 Audio Ocean, 33 more).
24 headphones stay below the audible-hiss threshold on the FiiO M11S but cross it on the FiiO M17 (64 Audio Fourte, AFUL Performer 8, Audio-Technica ATH-CKS1100, 21 more).
566 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 M11S and FiiO M17. Or put either against your own headphones in the source comparison tool.