The SMSL HO100 is a desktop amplifier at $160. It delivers 1.5 W into 32Ω and 200 mW into 300Ω, which ranks it 61 of 280 for raw power among the sources in this database.
Measured at 100 dB SPL it has comfortable headroom on 566 of the 567 dynamic and planar headphones catalogued here and enough but not generous on 1. Small balanced amp meant to sit under a matching DAC. SMSL publishes one power table without saying which jack it describes.
The manufacturer publishes 3.0 W into 16Ω, 1.5 W into 32Ω, 200 mW into 300Ω, 100 mW into 600Ω. The rest of the table is worked out from those.
The published figures describe the balanced output. A single-ended jack on the same unit will put out less — usually about half the voltage and a quarter of the power.
Derived rows hold output voltage steady, as an amplifier does (method).
Source: smsl-audio.com, smsl-audio.com.
| Load | Power | Status | How it was arrived at |
|---|---|---|---|
| 16 Ω | 3.0 W | Published | the manufacturer publishes this figure at this exact load |
| 32 Ω | 1.5 W | Published | the manufacturer publishes this figure at this exact load |
| 150 Ω | 354 mW | Derived | worked out between two published loads, holding output voltage linear between them |
| 300 Ω | 200 mW | Published | the manufacturer publishes this figure at this exact load |
| 600 Ω | 100 mW | Published | the manufacturer publishes this figure at this exact load |
Easiest to hardest to drive, with headroom at a 100 dB SPL peak.
| Headphone | Impedance | Sensitivity | Needs | Headroom | Verdict |
|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 114.0 dB/mW | 0.04 mW | +46 dB | Comfortable audible hiss |
| 64 Audio U12t | 12.6 Ω | 108.0 dB/mW | 0.16 mW | +42 dB | Comfortable faint hiss |
| Shure SE215 | 17 Ω | 107.0 dB/mW | 0.20 mW | +42 dB | Comfortable faint hiss |
| Moondrop Aria | 32 Ω | 107.1 dB/mW | 0.19 mW | +39 dB | Comfortable faint hiss |
| Audeze LCD-X 2021 | 20 Ω | 103.0 dB/mW | 0.50 mW | +37 dB | Comfortable faint hiss |
| Truthear Hexa | 20.5 Ω | 103.1 dB/mW | 0.49 mW | +37 dB | Comfortable faint hiss |
| Sennheiser IE 200 | 18 Ω | 101.6 dB/mW | 0.69 mW | +36 dB | Comfortable faint hiss |
| Sony MDR-7506 | 63 Ω | 106.0 dB/mW | 0.25 mW | +35 dB | Comfortable faint hiss |
| Meze 99 Classics | 32 Ω | 103.0 dB/mW | 0.50 mW | +35 dB | Comfortable faint hiss |
| Focal Clear MG | 55 Ω | 104.0 dB/mW | 0.40 mW | +33 dB | Comfortable |
| Philips SHP9500 | 32 Ω | 101.0 dB | 0.79 mW | +33 dB | Comfortable |
| Focal Utopia | 80 Ω | 104.0 dB/mW | 0.40 mW | +32 dB | Comfortable |
| Meze Empyrean | 32 Ω | 100.0 dB | 1.0 mW | +32 dB | Comfortable |
| Campfire Audio Andromeda 2020 | 9 Ω | 94.0 dB | 4.0 mW | +26 dB | Comfortable |
| Etymotic ER2SE | 15 Ω | 96.0 dB/mW | 2.5 mW | +30 dB | Comfortable |
| AKG K371 | 32 Ω | 99.1 dB/mW | 1.2 mW | +31 dB | Comfortable |
| Audio-Technica ATH-M50X | 38 Ω | 99.0 dB/mW | 1.3 mW | +30 dB | Comfortable |
| Beyerdynamic DT 900 Pro X | 48 Ω | 100.0 dB/mW | 1.0 mW | +30 dB | Comfortable |
| Audeze LCD-2 Classic | 70 Ω | 101.0 dB/mW | 0.79 mW | +30 dB | Comfortable |
| Grado SR80x | 38 Ω | 98.0 dB/mW | 1.6 mW | +29 dB | Comfortable |
| Sennheiser HD 560S | 120 Ω | 100.8 dB/mW | 0.83 mW | +27 dB | Comfortable |
| HiFiMAN Edition XS | 18 Ω | 92.0 dB | 6.3 mW | +26 dB | Comfortable |
| HiFiMAN Arya Stealth | 32 Ω | 94.0 dB | 4.0 mW | +26 dB | Comfortable |
| Dan Clark Audio AEON 2 Closed | 13 Ω | 90.0 dB/mW | 10 mW | +24 dB | Comfortable |
| Audeze LCD-5 | 14 Ω | 90.0 dB/mW | 10 mW | +24 dB | Comfortable |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 102.0 dB/mW | 0.63 mW | +26 dB | Comfortable |
| HiFiMAN HE400se | 25 Ω | 91.0 dB | 7.9 mW | +24 dB | Comfortable |
| HiFiMAN Sundara | 32 Ω | 92.0 dB | 6.3 mW | +24 dB | Comfortable |
| Dan Clark Audio Stealth | 23 Ω | 90.0 dB/mW | 10 mW | +23 dB | Comfortable |
| Fostex T50RP MK3 | 50 Ω | 92.0 dB/mW | 6.3 mW | +22 dB | Comfortable |
| AKG K702 | 62 Ω | 92.9 dB/mW | 5.1 mW | +22 dB | Comfortable |
| ZMF Verite Closed | 300 Ω | 99.0 dB/mW | 1.3 mW | +22 dB | Comfortable |
| Sennheiser HD 650 | 300 Ω | 97.8 dB/mW | 1.7 mW | +21 dB | Comfortable |
| Sennheiser HD 800S | 300 Ω | 96.8 dB/mW | 2.1 mW | +20 dB | Comfortable |
| Beyerdynamic DT 770 Pro (250Ω) | 250 Ω | 96.0 dB | 2.5 mW | +20 dB | Comfortable |
| Audio-Technica ATH-R70X | 470 Ω | 98.0 dB/mW | 1.6 mW | +19 dB | Comfortable |
| ZMF Atrium | 300 Ω | 96.0 dB/mW | 2.5 mW | +19 dB | Comfortable |
| Abyss AB-1266 Phi TC | 50 Ω | 88.0 dB/mW | 16 mW | +18 dB | Comfortable |
| Sennheiser HD 600 | 300 Ω | 91.8 dB/mW | 6.6 mW | +15 dB | Comfortable |
| HiFiMAN Susvara | 60 Ω | 83.0 dB | 50 mW | +12 dB | Comfortable |
At 1.3 µV of output noise, here is where that noise lands in the five most revealing in-ears in the database.
This one hisses. With the most sensitive in-ears in the database its own noise lands around 23 dB SPL, which you will hear between tracks and in quiet passages.
| In-ear | Impedance | Sensitivity | Hiss level |
|---|---|---|---|
| Simgot EA500 | 16 Ω | 141.0 dB/V | 23 dB SPL |
| Tanchjim EA FORCE | 17 Ω | 137.7 dB/V | 20 dB SPL |
| Shure SE846 | 9 Ω | 134.5 dB/V | 17 dB SPL |
| Campfire Audio Clara | 13.3 Ω | 134.1 dB/V | 16 dB SPL |
| 64 Audio Fourte | 10 Ω | 134.0 dB/V | 16 dB SPL |
At 0Ω output impedance this source satisfies the one-eighth rule with every headphone in the database, down to the 3Ω in-ears. Nothing here will have its frequency response shaped by the source.
| Source | Type | Price | Into 300 Ω | Output impedance | Output noise |
|---|---|---|---|---|---|
| Topping L30 II | desktop amplifier | $149 | 560 mW | 0.1 Ω | 0.3 µV |
Of the 280 sources here, 1 do everything the SMSL HO100 does as a headphone output: reach 100 dB on every headphone it reaches, stay inside the one-eighth rule wherever it does and stay under the audible-hiss threshold wherever it does. The cheapest of them is the Topping L30 II at $149, against this one’s $160 — $11 less.
This counts the headphone output only; inputs, converters, the volume control and the build are outside it.
$169 · 2.0 W into 32Ω · output Ω not published
Compare →$150 · 69 mW into 32Ω · output Ω not published
Compare →$149 · 2.7 W into 32Ω · 0.1 Ω out
Compare →$149 · 1.5 W into 32Ω · 1.8 Ω out
Compare →$149 · 1.5 W into 32Ω · 0.5 Ω out
Compare →$176 · 100 mW into 32Ω · output Ω not published
Compare →Compared with its closest rivals: vs ART HeadAmp 4 Pro · vs Fosi Audio SK02 · vs Little Dot MK II · vs PreSonus HP4 · vs Schiit Vali 2+ · vs SMSL SP400.