RME ADI-2 DAC FS: power output and what it will drive

The RME ADI-2 DAC FS is an audio interface at $1399. It delivers 1.2 W into 32Ω and 128 mW into 300Ω, which ranks it 70 of 280 for raw power among the sources in this database.

Measured at 100 dB SPL it has comfortable headroom on 564 of the 567 dynamic and planar headphones catalogued here, enough but not generous on 2 and only marginal on 1. Power is published at 16Ω, 32Ω; the rest of the table is derived from those figures. Output noise is not published, so the hiss estimate cannot be run.

The manufacturer publishes 940 mW into 16Ω, 1.2 W into 32Ω. The rest of the table is worked out from those.

Derived rows hold output voltage steady, as an amplifier does (method).

The noise figure above is converted, not read. RME does not print microvolts for this one. It prints a signal-to-noise ratio together with the voltage that ratio is referenced to, in the same block of the same table: “Signal-to-noise ratio (SNR) @ +7 dBu: 118 dB RMS unweighted, 121 dBA | Output level at 0 dBFS, Low Power, load 8 Ohm or up: +7 dBu (1.73 V)”. From those two numbers the noise follows by one division — 1.73 V ÷ 10^(118/20) — which is where the 2.18 µV comes from, at the Low Power (IEM) setting, podaje OBA: unweighted i A-weighted. This is the same situation as a sensitivity printed per volt instead of per milliwatt: published, but in a convention nobody converts.

Source: rme-audio.de.

Easiest to hardest to drive, with headroom at a 100 dB SPL peak.

At 2.18 µV of output noise, here is where that noise lands in the five most revealing in-ears in the database.

This one hisses. With the most sensitive in-ears in the database its own noise lands around 28 dB SPL, which you will hear between tracks and in quiet passages.

At 0.1Ω output impedance this source satisfies the one-eighth rule with every headphone in the database, down to the 3Ω in-ears. Nothing here will have its frequency response shaped by the source.

Check any pair.

Of the 280 sources here, 9 do everything the RME ADI-2 DAC FS does as a headphone output: reach 100 dB on every headphone it reaches, stay inside the one-eighth rule wherever it does and stay under the audible-hiss threshold wherever it does. The cheapest of them is the Schiit Magni Unity at $119, against this one’s $1399 — $1280 less, and a desktop amplifier rather than an audio interface.

This counts the headphone output only; inputs, converters, the volume control and the build are outside it.

Compared with its closest rivals: vs Apogee Symphony Desktop · vs Audient iD48 · vs RME Babyface Pro FS · vs RME Fireface UCX II · vs RME Fireface UFX II · vs RME Fireface UFX III.

Compare any two or match your own headphones. Every RME source here.