Both are audio interfaces, $199 against $809. 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?
The Audient iD44 MkII reaches 100 dB on 565 of the 567 models here, the Audient iD4 MkII on 561.
| Specification | Audient iD4 MkII | Audient iD44 MkII |
|---|---|---|
| Power into 32Ω | 112 mW | 190 mW |
| Power into 150Ω | 75 mW | 40 mW |
| Power into 300Ω | 55 mW | 42 mW |
| Power into 600Ω | 50 mW | 54 mW |
| Output impedance | not published | 50 Ω |
| Output noise | not published | not published |
| Price | $199 | $809 |
| Headphones it reaches 100 dB on out of 567 | 561 | 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.
4 headphones reach 100 dB on the Audient iD44 MkII but not on the Audient iD4 MkII — Moondrop COSMO, Symphonium Crimson, Symphonium Helios, 1 more.
561 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: Audient iD4 MkII and Audient iD44 MkII. Or put either against your own headphones in the source comparison tool.