Short answer
Both are audio interfaces, $1300 against $999.
The Audient iD48 reaches 100 dB on 566 of the 567 models here, the Universal Audio Volt 876 on 565.
| Specification | Audient iD48 | Universal Audio Volt 876 |
|---|---|---|
| Power into 32Ω | 528 mW | 225 mW |
| Power into 150Ω | 265 mW | 79 mW |
| Power into 300Ω | 168 mW | 65 mW |
| Power into 600Ω | 126 mW | 35 mW |
| Output impedance | 50 Ω | not published |
| Output noise | not published | not published |
| Price | $1300 | $999 |
| Headphones it reaches 100 dB on out of 567 | 566 | 565 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Load | Audient iD48 | Universal Audio Volt 876 |
|---|---|---|
| 32 Ω | Derived | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Published |
| 600 Ω | Published | Published |
Both makers publish a power rating. Audient iD48 publishes at 600 Ω; Universal Audio Volt 876 at 32 Ω, at 300 Ω and at 600 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 32 Ω and at 300 Ω only the Universal Audio Volt 876 figure is the maker’s own. On those rows the derived number is the one to doubt first.
1 headphone reaches 100 dB on the Audient iD48 but not on the Universal Audio Volt 876 — Moondrop PARA.
565 of the 567 models here reach 100 dB on both.
Headroom is at a 100 dB SPL peak.
The widest gap on the list is the HiFiMAN Susvara: Audient iD48 has +11 dB of headroom there against +4 dB. 6 dB is about 4.1 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Audient iD48 and Universal Audio Volt 876 because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | Audient iD48 headroom | Universal Audio Volt 876 headroom | Audient iD48 hiss | Universal Audio Volt 876 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +36 dB damping | +32 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +16 dB damping | +12 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +28 dB damping | +22 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +25 dB damping | +20 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +17 dB damping | +13 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +19 dB | +14 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +14 dB damping | +10 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +11 dB damping | +4 dB | not published | not published |
The Audient iD48 costs $301 more than the Universal Audio Volt 876. Out of the 567 models here, that difference buys 1 more model driven to 100 dB.
Nothing runs the other way: there is no axis here on which the cheaper of the two does better.
Only published figures count here; blank axes are counted separately.
Each in full: Audient iD48 and Universal Audio Volt 876.