Short answer
Both are dongles, both at $22.
The FiiO SnowSky Tiny B reaches 100 dB on 554 of the 567 models here, the FiiO SnowSky Tiny A on 550.
| Specification | FiiO SnowSky Tiny A | FiiO SnowSky Tiny B |
|---|---|---|
| Power into 32Ω | 34 mW | 34 mW |
| Power into 150Ω | 7.3 mW | 7.3 mW |
| Power into 300Ω | 3.6 mW | 3.6 mW |
| Power into 600Ω | 1.8 mW | 1.8 mW |
| Output impedance | 0.5 Ω | 1.0 Ω |
| Output noise | not published | not published |
| Price | $22 | $22 |
| Headphones it reaches 100 dB on out of 567 | 550 | 554 |
Not published means the maker leaves it out, so that axis cannot be compared.
| As published | FiiO SnowSky Tiny A | FiiO SnowSky Tiny B |
|---|---|---|
| Outputs | 3.5 mm | 3.5 mm + 4.4 mm (4.4 mm is internally unbalanced; both play simultaneously) |
| Connection | Direct plug-in USB-C (no cable); extra USB-C charging port for listen-and-charge | Direct plug-in design |
| Formats | PCM 384 kHz/32-bit, DSD256 | PCM 384 kHz/32-bit, DSD256 |
| Microphone | In-line controls and call recording supported | In-line controls and call recording supported |
Copied from the makers’ own pages: fiio.com/tiny. Battery life is the maker’s own test figure.
| Load | FiiO SnowSky Tiny A | FiiO SnowSky Tiny B |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Derived |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. FiiO SnowSky Tiny A publishes at 32 Ω; FiiO SnowSky Tiny B at 32 Ω. The other rows are worked out from those.
The two publish at the same loads, which is the one case where the rows of this table can be read straight across.
4 headphones reach 100 dB on the FiiO SnowSky Tiny B but not on the FiiO SnowSky Tiny A — Moondrop PARA 2, Moondrop VENUS, Symphonium Triton, 1 more.
14 headphones are left alone by the FiiO SnowSky Tiny A under the one-eighth rule but coloured by the FiiO SnowSky Tiny B (64 Audio Nio, 64 Audio Volur, Campfire Audio Andromeda 2023, 11 more).
550 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 Shure SE846: FiiO SnowSky Tiny B has +30 dB of headroom there against +28 dB. 2 dB is about 1.5 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for FiiO SnowSky Tiny A and FiiO SnowSky Tiny B because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | FiiO SnowSky Tiny A headroom | FiiO SnowSky Tiny B headroom | FiiO SnowSky Tiny A hiss | FiiO SnowSky Tiny B hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +28 dB | +30 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +8 dB | +10 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +13 dB | +13 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +8 dB | +8 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +7 dB | +7 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +2 dB | +2 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | -3 dB | -3 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | -4 dB | -4 dB | not published | not published |
These two cost the same, $22, so price settles nothing. Out of the 567 models here, the FiiO SnowSky Tiny A leaves 14 models alone under the one-eighth rule; the FiiO SnowSky Tiny B drives 4 models to 100 dB — and that is the whole of it on these three axes.
Only published figures count here; blank axes are counted separately.
Each in full: FiiO SnowSky Tiny A and FiiO SnowSky Tiny B.