Short answer
Both are desktop amplifiers, $176 against $229.
The Topping L50 reaches 100 dB on 567 of the 567 models here, the Little Dot MK II on 560.
| Specification | Little Dot MK II | Topping L50 |
|---|---|---|
| Power into 32Ω | 100 mW | 2.8 W |
| Power into 150Ω | 214 mW | 933 mW |
| Power into 300Ω | 300 mW | 540 mW |
| Power into 600Ω | 150 mW | 290 mW |
| Output impedance | not published | 0.1 Ω |
| Output noise | not published | not published |
| Price | $176 | $229 |
| Headphones it reaches 100 dB on out of 567 | 560 | 567 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Load | Little Dot MK II | Topping L50 |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Published |
| 600 Ω | Derived | Published |
Both makers publish a power rating. Little Dot MK II publishes at 32 Ω and at 300 Ω; Topping L50 at 32 Ω, at 300 Ω and at 600 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 600 Ω only the Topping L50 figure is the maker’s own. On those rows the derived number is the one to doubt first.
7 headphones reach 100 dB on the Topping L50 but not on the Little Dot MK II — Moondrop COSMO, Moondrop PARA, Moondrop PARA 2, 4 more.
560 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: Topping L50 has +27 dB of headroom there against +8 dB. 18 dB is about 70 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Little Dot MK II and Topping L50 because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | Little Dot MK II headroom | Topping L50 headroom | Little Dot MK II hiss | Topping L50 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +28 dB | +47 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +8 dB | +27 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +22 dB | +34 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +26 dB | +30 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +10 dB | +26 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +21 dB | +24 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +17 dB | +19 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +4 dB | +16 dB | not published | not published |
The Topping L50 costs $53 more than the Little Dot MK II. Out of the 567 models here, that difference buys 7 more models driven to 100 dB.
Nothing runs the other way: there is no axis here on which the cheaper of the two does better.
Only published figures count here; blank axes are counted separately.
Each in full: Little Dot MK II and Topping L50.