FiiO KA17 vs Hidizs S9 Pro Plus

Both are dongles, $149 against $139.

The FiiO KA17 reaches 100 dB on 564 of the 567 models here, the Hidizs S9 Pro Plus on 562.

Not published means the maker leaves it out, so that axis cannot be compared.

Through the balanced sockets the FiiO KA17 reaches 100 dB on 565 of the 567 models here and the Hidizs S9 Pro Plus on 564. Derived figures are worked out from the loads the maker did publish.

Both makers publish a power rating. FiiO KA17 publishes at 32 Ω and at 300 Ω; Hidizs S9 Pro Plus 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 KA17 figure is the maker’s own. On those rows the derived number is the one to doubt first.

What the labels mean.

2 headphones reach 100 dB on the FiiO KA17 but not on the Hidizs S9 Pro Plus — Moondrop COSMO, Symphonium Helios.

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 Shure SE846: FiiO KA17 has +32 dB of headroom there against +30 dB. 2 dB is about 1.6 times the power, which matters for peaks rather than for how loud the music sits.

The hiss columns are empty for Hidizs S9 Pro Plus because that maker publishes no output noise figure.

The FiiO KA17 costs $10 more than the Hidizs S9 Pro Plus. Out of the 567 models here, that difference buys 2 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: FiiO KA17 and Hidizs S9 Pro Plus.