Both are desktop amplifiers, $150 against $160. 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 SMSL HO100 reaches 100 dB on 567 of the 567 models here, the PreSonus HP4 on 558.
| Specification | PreSonus HP4 | SMSL HO100 |
|---|---|---|
| Power into 32Ω | 69 mW | 1.5 W |
| Power into 150Ω | 52 mW | 354 mW |
| Power into 300Ω | 26 mW | 200 mW |
| Power into 600Ω | 13 mW | 100 mW |
| Output impedance | not published | <0.1 Ω |
| Output noise | not published | 1.3 µV |
| Price | $150 | $160 |
| Headphones it reaches 100 dB on out of 567 | 558 | 567 |
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.
9 headphones reach 100 dB on the SMSL HO100 but not on the PreSonus HP4 — Moondrop COSMO, Moondrop PARA, Moondrop PARA 2, 6 more.
558 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: PreSonus HP4 and SMSL HO100. Or put either against your own headphones in the source comparison tool.