For every other source in this database there is a cheaper one that does the same job as a headphone output: it reaches 100 dB on every headphone the dearer one reaches, and where the dearer one publishes an output impedance or a noise figure, it matches that too. These 15 are the exceptions. Nothing below their price does everything they do.
The list is short and it is cheap, and both of those are the point. The dearest thing on it is the Topping L30 II at $149, and 215 products here cost more than that — every one of them with something cheaper that matches it on the three numbers a maker can be held to. That is not a claim that those products are the same. It is a claim about what a specification sheet can settle, and where it stops being the thing you are paying for.
Two cautions. A figure its maker never published cannot count against a product, so a source that prints nothing is easier to match than one that prints everything — which is the opposite of a reward for silence, but it is worth knowing how the count works. And this measures a headphone output: inputs, converters, microphone preamps, balanced outputs, controls and build are all outside it, and any of them can be a perfectly good reason to spend more. What makers do and do not print is its own page.
| Source | Price | Type | Output impedance | Output noise |
|---|---|---|---|---|
| Apple USB-C dongle (EU) | $9 | USB dongle | not published | not published |
| Apple USB-C dongle (US) | $9 | USB dongle | not published | not published |
| Generic CX31993 dongles | $12 | USB dongle | not published | not published |
| JadeAudio JA11 | $20 | USB dongle | 0.5 Ω | 1.7 µV |
| FiiO SnowSky Tiny A | $22 | USB dongle | 0.5 Ω | not published |
| FiiO SnowSky Tiny B | $22 | USB dongle | 1 Ω | not published |
| FiiO KA11 | $29 | USB dongle | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | Bluetooth receiver | 0.5 Ω | 8 µV |
| FiiO BTR13 | $59 | Bluetooth receiver | 0.6 Ω | 1 µV |
| iFi GO link | $59 | USB dongle | 0.4 Ω | not published |
| iBasso DC03 Pro | $69 | USB dongle | 0.12 Ω | 0.9 µV |
| FiiO KA5 | $99 | USB dongle | 0.3 Ω | 1.6 µV |
| Schiit Magni Heresy | $99 | desktop amplifier | 0.25 Ω | not published |
| Schiit Magni Unity | $119 | desktop amplifier | 0.1 Ω | 1.59 µV |
| Topping L30 II | $149 | desktop amplifier | 0.1 Ω | 0.3 µV |
265 of the 280 sources in this database are not on this list because something cheaper in this database does the same job as a headphone output: it reaches 100 dB on every headphone they reach, and matches them wherever their own makers published an output impedance or a noise figure. That is an arithmetic result on three numbers, not a verdict on the products — everything a spec sheet cannot settle is outside it.
This is not a ranking of sound quality and cannot be. It is ordered by price and selected on numbers that manufacturers printed, and manufacturers do not print anything about how their products sound. Every row links to that product’s own page, where each figure is labelled with the document it came from.
Quietest sources for sensitive in-ears · Lowest published output impedance · Most power into 300 Ω · Ranges printed with a tolerance · Sources with a complete spec sheet · Sources that drive everything here · Audio interfaces as headphone amplifiers · Sources under $100 · Hardest headphones to drive · Most sensitive in-ears · Quietest desktop sources · What balanced actually gains · Portable players by power · Most power per dollar · High-impedance headphones