Both are dongles, $79 against $99. This page puts them side by side on the only three things a maker can be held to — power, output impedance and noise — and then asks the question that actually matters: which headphones do they treat differently?
On raw power they are level: each reaches 100 dB on 565 of the 567 non-electrostatic models here.
| Specification | FiiO KA3 | FiiO KA5 |
|---|---|---|
| Power into 32Ω | 130 mW | 122 mW |
| Power into 150Ω | 28 mW | 26 mW |
| Power into 300Ω | 14 mW | 14 mW |
| Power into 600Ω | 7.0 mW | 6.8 mW |
| Output impedance | 0.5 Ω | 0.3 Ω |
| Output noise | 1.7 µV | 1.6 µV |
| Price | $79 | $99 |
| Headphones it reaches 100 dB on out of 567 | 565 | 565 |
A figure marked not published is missing from the maker’s own material, which is not the same as being good or bad. Where one of these two publishes a number and the other does not, the comparison on that axis cannot be made at all — and saying so is more useful than guessing.
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.
1 headphone is left alone by the FiiO KA5 under the one-eighth rule but coloured by the FiiO KA3 (Symphonium Titan).
565 of the 567 models here reach 100 dB on both. That is a power count and nothing more; whether either source suits a given headphone also depends on the two lines above.
Each has a page of its own with every power figure traced to what the maker published and a full headphone list: FiiO KA3 and FiiO KA5. Or put either against your own headphones in the source comparison tool.