Short answer
Both are portable players, $499 against $480.
On raw power they are level: each reaches 100 dB on 566 of the 567 non-electrostatic models here.
| Specification | FiiO M11S | iBasso DX180 |
|---|---|---|
| Power into 32Ω | 200 mW | 262 mW |
| Power into 150Ω | 44 mW | 56 mW |
| Power into 300Ω | 23 mW | 28 mW |
| Power into 600Ω | 12 mW | 14 mW |
| Output impedance | 1.5 Ω | 0.6 Ω |
| Output noise | 1.8 µV | not published |
| Price | $499 | $480 |
| Headphones it reaches 100 dB on out of 567 | 566 | 566 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | FiiO M11S | iBasso DX180 |
|---|---|---|
| Socket | 4.4mm | 4.4mm |
| Power into 32Ω | 670 mW | 690 mW |
| Power into 300Ω | 90 mW | 74 mW derived |
| Output impedance | 2.6 Ω | 1.1 Ω |
| Output noise | 3.1 µV | not published |
| Headphones it reaches 100 dB on out of 567 | 566 | 566 |
Through the balanced sockets the two are level on the same test: each reaches 100 dB on 566 of the 567 models here. Derived figures are worked out from the loads the maker did publish.
| Load | FiiO M11S | iBasso DX180 |
|---|---|---|
| 32 Ω | Published | Derived |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Derived |
| 600 Ω | Derived | Derived |
Only one of these two columns starts from a power rating. FiiO M11S publishes one at 32 Ω and at 300 Ω; iBasso DX180 publishes none at any of these four loads, so its column is worked out from power it published at other loads. Both are arithmetic on a maker’s own figures rather than guesses, and the method used for the iBasso DX180 understates rather than flatters — but at 32 Ω and at 300 Ω are the only loads here at which its maker can be held to a figure.
On power they are interchangeable across this whole database: there is no headphone here that one reaches 100 dB on and the other does not.
50 headphones are left alone by the iBasso DX180 under the one-eighth rule but coloured by the FiiO M11S (64 Audio Aspire 1, 64 Audio Fourte, 64 Audio Nio, 47 more).
566 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: iBasso DX180 has +19 dB of headroom there against +16 dB. 2 dB is about 1.8 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for iBasso DX180 because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | FiiO M11S headroom | iBasso DX180 headroom | FiiO M11S hiss | iBasso DX180 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +36 dB damping | +39 dB | 20 dB | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +16 dB damping | +19 dB | -0 dB | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +21 dB | +22 dB | -2 dB | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +16 dB | +17 dB | -7 dB | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +15 dB | +16 dB | -8 dB | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +10 dB | +11 dB | -14 dB | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +5 dB | +6 dB | -18 dB | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +3 dB | +4 dB | -20 dB | not published |
The FiiO M11S costs $19 more than the iBasso DX180, and on these three axes the money buys nothing: among the 567 models here there is not one that the FiiO M11S handles and the iBasso DX180 does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper iBasso DX180 leaves 50 models alone under the one-eighth rule that the FiiO M11S does not.
Only published figures count here; blank axes are counted separately.
Each in full: FiiO M11S and iBasso DX180.