Audient iD48: power output and what it will drive

The Audient iD48 is an audio interface at $1300. It delivers 528 mW into 32Ω and 168 mW into 300Ω, which ranks it 104 of 280 for raw power among the sources in this database.

Measured at 100 dB SPL it has comfortable headroom on 557 of the 567 dynamic and planar headphones catalogued here, enough but not generous on 8, only marginal on 1 and not enough power for 1. Power is published at 30Ω, 60Ω, 600Ω; the rest of the table is derived from those figures. Output noise is not published, so the hiss estimate cannot be run. Audient prints a peak voltage, an RMS voltage and a power on the same line, and the power is about twice what its own RMS voltage gives. The figures here are the ones Audient printed; the <a href="/amp-spec-audit/">amplifier audit</a> works through the discrepancy.

The manufacturer publishes 530 mW into 30Ω, 565 mW into 60Ω, 126 mW into 600Ω. Everything else in the table above is worked out from those figures, and this table says which is which.

Derivation holds output voltage steady between and beyond the published loads rather than output power, because that is what an amplifier actually does. The full method is written up here.

Source: audient.com.

Ordered from easiest to hardest to drive. Headroom is measured at 100 dB SPL, which is louder than almost anyone listens — a small negative number means the source still plays loud, just without reserve for peaks.

These figures come from each manufacturer's own sensitivity rating. A handful of planars — the HiFiMAN Susvara and the Abyss AB-1266 in particular — are widely reported to need far more than their published sensitivity implies, so treat a bare pass on those as optimistic rather than settled.

The manufacturer does not publish an output noise figure for this source, so the hiss estimate that runs on every other page here cannot be run on this one. Rather than substitute a plausible number, this page leaves the question open.

If you know the noise figure from a measurement you trust, the hiss calculator takes it directly and tells you where that noise lands in your own in-ears.

At 50Ω output impedance, the one-eighth rule says this source suits headphones of 400.0Ω and above. 561 of the 567 models here fall below that. That is most of the database, not a niche — 222 of them multi-driver in-ears, and the mismatch tilts the frequency response audibly rather than subtly.

The rule is a rule of thumb, not physics: a source impedance below one eighth of the headphone's keeps the interaction under about 1 dB. The checker works it out for any pair.

Of the 280 sources here, 67 do everything the Audient iD48 does as a headphone output: reach 100 dB on every headphone it reaches and stay inside the one-eighth rule wherever it does. The cheapest of them is the FiiO KA11 at $29, against this one’s $1300 — $1271 less, and a USB dongle rather than an audio interface.

The cheaper one also publishes a noise figure, which the Audient iD48 does not — so on the paperwork it is ahead, not merely level.

This counts a headphone output and nothing else. Inputs, converters, microphone preamps, balanced outputs, the volume control, the case and the warranty are all outside it, and any of them can be the reason to buy the dearer box. What the count does say is that the three numbers a maker can be held to do not separate them.

Worked out in advance against its closest rivals: vs Audient EVO 16 · vs Audient EVO 4 · vs Audient EVO 8 · vs Audient Horizon 8P · vs Audient iD14 MkII · vs Audient iD24 · vs Audient iD4 MkII · vs Audient iD44 MkII · vs Audient NERO · vs RME ADI-2 DAC FS · vs RME Fireface UCX II · vs Universal Audio Volt 876. Each of those pages lists the headphones that tell the two apart.

Or put any two side by side in the source comparison tool, or run your own headphones through the amplifier matcher. Or see every Audient source in the database, and how much of what this site says about them came from Audient’s own documents.