The Zoom UAC-232 is a audio interface at $399. It delivers 148 mW into 32Ω and 28 mW into 300Ω, which ranks it 107 of 156 for raw power among the sources in this database.
Measured at 100 dB SPL it has comfortable headroom on 373 of the 396 dynamic and planar headphones catalogued here, enough but not generous on 21 and not enough power for 2.
The manufacturer publishes 100 mW into 63Ω. 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: zoomcorp.com.
| Load | Power | Status | How it was arrived at |
|---|---|---|---|
| 32 Ω | 148 mW | Derived | worked out from the published figure and the published output impedance, through the divider that impedance creates |
| 63 Ω | 100 mW | Published | the manufacturer publishes this figure at this exact load |
| 150 Ω | 51 mW | Derived | worked out from the published figure and the published output impedance, through the divider that impedance creates |
| 300 Ω | 28 mW | Derived | worked out from the published figure and the published output impedance, through the divider that impedance creates |
| 600 Ω | 14 mW | Derived | worked out from the published figure and the published output impedance, through the divider that impedance creates |
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 HE-6se 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.
| Headphone | Impedance | dB/mW | Needs | Headroom | Verdict |
|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 114.0 | 0.04 mW | +30 dB | Comfortable damping |
| 64 Audio U12t | 13 Ω | 108.0 | 0.16 mW | +26 dB | Comfortable damping |
| Shure SE215 | 17 Ω | 107.0 | 0.20 mW | +26 dB | Comfortable damping |
| Moondrop Aria | 32 Ω | 107.1 | 0.19 mW | +29 dB | Comfortable damping |
| Audeze LCD-X 2021 | 20 Ω | 103.0 | 0.50 mW | +23 dB | Comfortable damping |
| Truthear Hexa | 21 Ω | 103.1 | 0.49 mW | +23 dB | Comfortable damping |
| Sennheiser HD 25 (1-II) | 70 Ω | 108.0 | 0.16 mW | +28 dB | Comfortable damping |
| Sennheiser IE 200 | 18 Ω | 101.6 | 0.69 mW | +21 dB | Comfortable damping |
| Sony MDR-7506 | 63 Ω | 106.0 | 0.25 mW | +26 dB | Comfortable damping |
| Meze 99 Classics | 32 Ω | 103.0 | 0.50 mW | +25 dB | Comfortable damping |
| Focal Clear MG | 55 Ω | 104.0 | 0.40 mW | +24 dB | Comfortable damping |
| Philips SHP9500 | 32 Ω | 101.0 | 0.79 mW | +23 dB | Comfortable damping |
| Focal Utopia | 80 Ω | 104.0 | 0.40 mW | +23 dB | Comfortable damping |
| Meze Empyrean | 32 Ω | 100.0 | 1.0 mW | +22 dB | Comfortable damping |
| Campfire Audio Andromeda 2020 | 9 Ω | 94.0 | 4.0 mW | +10 dB | Comfortable damping |
| Etymotic ER2SE | 15 Ω | 96.0 | 2.5 mW | +14 dB | Comfortable damping |
| AKG K371 | 32 Ω | 99.1 | 1.2 mW | +21 dB | Comfortable damping |
| Audio-Technica ATH-M50X | 38 Ω | 99.0 | 1.3 mW | +20 dB | Comfortable damping |
| Beyerdynamic DT 900 Pro X | 48 Ω | 100.0 | 1.0 mW | +21 dB | Comfortable damping |
| Audeze LCD-2 Classic | 70 Ω | 101.0 | 0.79 mW | +21 dB | Comfortable damping |
| Grado SR80x | 38 Ω | 98.0 | 1.6 mW | +19 dB | Comfortable damping |
| Sennheiser HD 560S | 120 Ω | 100.8 | 0.83 mW | +19 dB | Comfortable |
| HiFiMAN Edition XS | 18 Ω | 92.0 | 6.3 mW | +11 dB | Comfortable damping |
| HiFiMAN Arya Stealth | 32 Ω | 94.0 | 4.0 mW | +16 dB | Comfortable damping |
| Dan Clark Audio AEON 2 Closed | 13 Ω | 90.0 | 10 mW | +8 dB | Enough damping |
| Audeze LCD-5 | 14 Ω | 90.0 | 10 mW | +8 dB | Enough damping |
| HiFiMAN Sundara | 37 Ω | 94.0 | 4.0 mW | +15 dB | Comfortable damping |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 102.0 | 0.63 mW | +17 dB | Comfortable |
| HiFiMAN HE400se | 25 Ω | 91.0 | 7.9 mW | +12 dB | Comfortable damping |
| Dan Clark Audio Stealth | 23 Ω | 90.0 | 10 mW | +10 dB | Comfortable damping |
| Fostex T50RP MK3 | 50 Ω | 92.0 | 6.3 mW | +12 dB | Comfortable damping |
| AKG K702 | 62 Ω | 92.9 | 5.1 mW | +13 dB | Comfortable damping |
| ZMF Verite Closed | 300 Ω | 99.0 | 1.3 mW | +13 dB | Comfortable |
| Sennheiser HD 650 | 300 Ω | 97.8 | 1.7 mW | +12 dB | Comfortable |
| Sennheiser HD 800S | 300 Ω | 96.8 | 2.1 mW | +11 dB | Comfortable |
| Beyerdynamic DT 770 Pro (250Ω) | 250 Ω | 96.0 | 2.5 mW | +11 dB | Comfortable |
| Audio-Technica ATH-R70X | 470 Ω | 98.0 | 1.6 mW | +11 dB | Comfortable |
| ZMF Atrium | 300 Ω | 96.0 | 2.5 mW | +10 dB | Comfortable |
| Abyss AB-1266 Phi TC | 50 Ω | 88.0 | 16 mW | +8 dB | Enough damping |
| Sennheiser HD 600 | 300 Ω | 91.8 | 6.6 mW | +6 dB | Enough |
| HiFiMAN Susvara | 60 Ω | 83.0 | 50 mW | +3 dB | Enough damping |
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 12 Ω output impedance, the one-eighth rule says this source suits headphones of 96.0Ω and above. 350 of the 396 models here fall below that, mostly multi-driver in-ears, where 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.
$349 · 112 mW into 32Ω · not published out
Compare →$349 · 80 mW into 32Ω · not published out
Compare →$299 · 84 mW into 32Ω · not published out
Compare →$299 · 240 mW into 32Ω · 0.5 Ω out
Compare →$299 · 86 mW into 32Ω · not published out
Compare →$299 · 374 mW into 32Ω · 1 Ω out
Compare →Or put any two side by side in the source comparison tool, or run your own headphones through the amplifier matcher.