The Moondrop PARA 2 is 9Ω with a sensitivity of 85.5 dB/mW, which is 106.0 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 28 mW, or 0.50 V across the drivers.
That is a moderate load. Most USB dongles handle it without complaint; the weakest phone outputs will run out of volume before they run out of quality. 173 of 280 sources here have enough headroom. The cheapest portable source that does the job is the FiiO KA11 at $29.
Sensitivity here is in dB per milliwatt. Why the unit matters.
Moondrop publishes this as 106 dB/Vrms (@1kHz) — a figure per volt, not per milliwatt. At 9Ω the two differ by 20.5 dB, so the 85.5 dB/mW above is that published number converted, not a different measurement.
This is the conversion that online calculators skip. Quote the per-volt number as if it were per-milliwatt and this headphone looks 20 dB easier to drive than it is — which is roughly the difference between a dongle being enough and not being enough.
Source: moondroplab.com. How this data was built.
| As it is labelled | As printed | Tolerance | Standard |
|---|---|---|---|
| Frequency Response | 20Hz-42kHz (IEC61094, Free Field) | not printed | IEC61094 (free field) |
| Effective Frequency Response | 20Hz-20kz (IEC60318-4, -3dB) | -3 dB | IEC60318-4 |
Moondrop prints two frequency ranges for the Moondrop PARA 2. The wide one carries no conditions at all; the narrow one names a measurement standard and a tolerance. Only the second is a specification — the first is a headline.
Moondrop prints the narrow range as “20Hz-20kz”, without the H. It is quoted here exactly as it stands on the page.
This is one of only 58 models — out of the 490 whose maker prints a range at all — that also print the tolerance. That is what makes it a specification rather than a headline.
Only what the maker printed; maker by maker.
| Level | What it is | Power | Voltage | Current |
|---|---|---|---|---|
| 85 dB SPL | quiet background listening | 0.89 mW | 90 mV | 10.0 mA |
| 95 dB SPL | normal listening | 8.9 mW | 0.28 V | 31.5 mA |
| 100 dB SPL | loud listening | 28 mW | 0.50 V | 56.0 mA |
| 105 dB SPL | very loud | 89 mW | 0.90 V | 99.5 mA |
| 110 dB SPL | peaks on dynamic music | 282 mW | 1.59 V | 177.0 mA |
Most people listen between 75 and 85 dB; the 100 dB row leaves room for peaks.
The 15 cheapest of the 280 sources here that reach 100 dB SPL into 9Ω with at least 10 dB of headroom and no known hiss or output-impedance problem with these headphones. All 280 sources, judged for these headphones.
| Source | Type | Price | Power into 9Ω | Headroom | Verdict |
|---|---|---|---|---|---|
| Schiit Magni Heresy | desktop amplifier | $99 | 1.6 W | +17 dB | Comfortable |
| Schiit Magni+ | desktop amplifier | $109 | 562 mW | +13 dB | Comfortable |
| Schiit Magni Unity | desktop amplifier | $119 | 1.7 W | +18 dB | Comfortable |
| JDS Labs Atom Amp 2 | desktop amplifier | $129 | 745 mW | +14 dB | Comfortable |
| Schiit Vali 3 | desktop amplifier | $149 | 422 mW | +12 dB | Comfortable |
| Topping L30 II | desktop amplifier | $149 | 2.0 W | +18 dB | Comfortable |
| SMSL HO100 | desktop amplifier | $160 | 1.7 W | +18 dB | Comfortable |
| xDuoo MT-604 | desktop amplifier | $169 | 562 mW | +13 dB | Comfortable |
| FiiO K7 | desktop DAC/amp | $199 | 343 mW | +11 dB | Comfortable |
| iFi Zen CAN | desktop amplifier | $199 | 450 mW | +12 dB | Comfortable |
| Geshelli Archel Pro | desktop amplifier | $200 | 506 mW | +13 dB | Comfortable |
| Schiit Magni Piety | desktop amplifier | $200 | 675 mW | +14 dB | Comfortable |
| SMSL C200 | desktop DAC/amp | $219 | 1.5 W | +17 dB | Comfortable |
| Schiit Midgard | desktop amplifier | $219 | 3.1 W | +20 dB | Comfortable |
| Topping L50 | desktop amplifier | $229 | 2.0 W | +18 dB | Comfortable |
Hiss. At 106.0 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Mjolnir 3, would put its hiss at roughly 14 dB SPL in these headphones — clearly audible in quiet passages. Check your own source.
Output impedance. At 9Ω these want a source output impedance below 1.12Ω to satisfy the one-eighth rule; 49 of the 192 sources that publish one miss it. Check yours here.
8Ω · 80.0 dB/mW · Demanding
See requirements →15Ω · 81.8 dB/mW · Moderate
See requirements →18Ω · 82.6 dB/mW · Moderate
See requirements →62Ω · 92.9 dB/mW · Moderate
See requirements →62Ω · 92.9 dB/mW · Moderate
See requirements →62Ω · 92.9 dB/mW · Moderate
See requirements →