Short answer
Both are portable players, $499 against $479.
The FiiO M11S reaches 100 dB on 566 of the 567 models here, the Shanling M3 Ultra on 562.
| Specification | FiiO M11S | Shanling M3 Ultra |
|---|---|---|
| Power into 32Ω | 200 mW | 140 mW |
| Power into 150Ω | 44 mW | 30 mW |
| Power into 300Ω | 23 mW | 15 mW |
| Power into 600Ω | 12 mW | 7.5 mW |
| Output impedance | 1.5 Ω | 1 Ω |
| Output noise | 1.8 µV | not published |
| Price | $499 | $479 |
| Headphones it reaches 100 dB on out of 567 | 566 | 562 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | FiiO M11S | Shanling M3 Ultra |
|---|---|---|
| Socket | 4.4mm | 4.4mm |
| Power into 32Ω | 670 mW | 260 mW |
| Power into 300Ω | 90 mW | 28 mW derived |
| Output impedance | 2.6 Ω | 1 Ω |
| Output noise | 3.1 µV | not published |
| Headphones it reaches 100 dB on out of 567 | 566 | 565 |
Through the balanced sockets the FiiO M11S reaches 100 dB on 566 of the 567 models here and the Shanling M3 Ultra on 565. Derived figures are worked out from the loads the maker did publish.
| Load | FiiO M11S | Shanling M3 Ultra |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Derived |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. FiiO M11S publishes at 32 Ω and at 300 Ω; Shanling M3 Ultra at 32 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 300 Ω only the FiiO M11S figure is the maker’s own. On those rows the derived number is the one to doubt first.
4 headphones reach 100 dB on the FiiO M11S but not on the Shanling M3 Ultra — Moondrop COSMO, Moondrop PARA, Symphonium Crimson, 1 more.
36 headphones are left alone by the Shanling M3 Ultra under the one-eighth rule but coloured by the FiiO M11S (64 Audio Aspire 1, 64 Audio Fourte, 64 Audio Ocean, 33 more).
562 of the 567 models here reach 100 dB on both.
Headroom is at a 100 dB SPL peak.
The widest gap on the list is the Campfire Audio Andromeda 2020: FiiO M11S has +16 dB of headroom there against +10 dB. 6 dB is about 4.3 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Shanling M3 Ultra because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | FiiO M11S headroom | Shanling M3 Ultra headroom | FiiO M11S hiss | Shanling M3 Ultra hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +36 dB damping | +30 dB | 20 dB | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +16 dB damping | +10 dB | -0 dB | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +21 dB | +19 dB | -2 dB | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +16 dB | +15 dB | -7 dB | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +15 dB | +11 dB | -8 dB | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +10 dB | +8 dB | -14 dB | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +5 dB | +4 dB | -18 dB | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +3 dB | +2 dB | -20 dB | not published |
The FiiO M11S costs $20 more than the Shanling M3 Ultra. Out of the 567 models here, that difference buys 4 more models driven to 100 dB.
It does not run one way only: the cheaper Shanling M3 Ultra leaves 36 models alone under the one-eighth rule that the FiiO M11S does not, which is the part worth checking against your own headphones before paying the difference.
Only published figures count here; blank axes are counted separately.
Each in full: FiiO M11S and Shanling M3 Ultra.