Audient iD4 MkII: power output and what it will drive

The Audient iD4 MkII is an audio interface at $199. It delivers 112 mW into 32Ω and 55 mW into 300Ω, which ranks it 206 of 280 for raw power among the sources in this database.

Measured at 100 dB SPL it has comfortable headroom on 528 of the 567 dynamic and planar headphones catalogued here, enough but not generous on 29, only marginal on 4 and not enough power for 6. Power is published at 30Ω, 62Ω, 600Ω; the rest of the table is derived from those figures. Output impedance is not published. Output noise is not published, so the hiss estimate cannot be run.

This entry does not repeat the manufacturer's printed power figures. It uses 111 mW into 30Ω, 140 mW into 62Ω, 50 mW into 600Ω.

The power figures above are not the ones Audient prints, and that is deliberate. Audient publishes a peak voltage, an RMS voltage and a power figure on the same line — and the power is twice what the RMS voltage gives. On the iD4 MkII, 1.827 Vrms into 30Ω is 111 mW; Audient prints 223 mW. The same factor runs through all nine published points across the iD4 MkII, iD24 and EVO 4 — six of them within 1% of 2.00 and the other three 3–6% below it, the sort of spread two- and three-digit printed figures produce — so it is systematic rather than a slip on one line. Two things would produce it: squaring the peak voltage instead of the RMS one, or quoting both channels added together. The arithmetic cannot tell those apart — V_pk²/R and 2·V_rms²/R are the same number — and Audient does not say which it is. So this database does not guess at the cause. It applies one rule that follows straight from their own document: the power here is V_rms²/R computed from the RMS voltage Audient prints beside each load. That comes out at half the printed power, give or take the rounding of their figures. The voltages themselves are untouched, and they are what the matching maths on this page relies on.

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

Source: support.audient.com, audient.com.

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

The manufacturer does not publish an output noise figure for this source, so there is no hiss estimate here. If you have a measured figure, the hiss calculator takes it.

The manufacturer does not publish an output impedance for this source. Without it, nothing here can say how this source will behave with a multi-driver in-ear.

With a measured figure, the checker works out the consequence.

Of the 280 sources here, 46 do everything the Audient iD4 MkII does as a headphone output: reach 100 dB on every headphone it reaches. The cheapest of them is the FiiO KA11 at $29, against this one’s $199 — $170 less, and a USB dongle rather than an audio interface.

The cheaper one also publishes an output impedance and a noise figure, which the Audient iD4 MkII does not — so on the paperwork it is ahead, not merely level.

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

Compared with its closest rivals: vs Audient EVO 16 · vs Audient EVO 4 · vs Audient EVO 8 · vs Audient Horizon 8P · vs Audient iD44 MkII · vs Audient iD48 · vs Audient NERO · vs Audient ORIA · vs Focusrite Scarlett 2i2 4th gen · vs Steinberg UR22C · vs Steinberg UR24C · vs Tascam US-2x2HR · vs Universal Audio Volt 2 · vs Zoom AMS-44.

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