Short answer
Both are audio interfaces, $299 against $199.
The Apogee BOOM reaches 100 dB on 565 of the 567 models here, the Steinberg UR22C on 512.
| Specification | Apogee BOOM | Steinberg UR22C |
|---|---|---|
| Power into 32Ω | 240 mW | 12 mW |
| Power into 150Ω | 51 mW | 4.0 mW |
| Power into 300Ω | 26 mW | 2.0 mW |
| Power into 600Ω | 13 mW | 1.0 mW |
| Output impedance | 0.5 Ω | not published |
| Output noise | not published | not published |
| Price | $299 | $199 |
| Headphones it reaches 100 dB on out of 567 | 565 | 512 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Load | Apogee BOOM | Steinberg UR22C |
|---|---|---|
| 32 Ω | Published | Derived |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Derived |
| 600 Ω | Derived | Derived |
Only one of these two columns starts from a power rating. Apogee BOOM publishes one at 32 Ω; Steinberg UR22C publishes none at any of these four loads, so its column is worked out from power it published at other loads. Both are arithmetic on a maker’s own figures rather than guesses, and the method used for the Steinberg UR22C understates rather than flatters — but at 32 Ω is the only load here at which its maker can be held to a figure.
53 headphones reach 100 dB on the Apogee BOOM but not on the Steinberg UR22C — AKG K612 Pro, Abyss AB-1266 Phi CC, Abyss AB-1266 Phi TC, 50 more.
512 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 Shure SE846: Apogee BOOM has +32 dB of headroom there against +19 dB. 13 dB is about 20 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Apogee BOOM and Steinberg UR22C because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | Apogee BOOM headroom | Steinberg UR22C headroom | Apogee BOOM hiss | Steinberg UR22C hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +32 dB | +19 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +12 dB | -1 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +21 dB | +10 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +17 dB | +6 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +14 dB | +1 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +10 dB | -1 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +6 dB | -5 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +4 dB | -7 dB | not published | not published |
The Apogee BOOM costs $100 more than the Steinberg UR22C. Out of the 567 models here, that difference buys 53 more models 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: Apogee BOOM and Steinberg UR22C.