Moondrop Dusk (2024): how much amplifier do you need?

The Moondrop Dusk (2024) is 14.5Ω with a sensitivity of 100.6 dB/mW, which is 119.0 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 0.87 mW, or 0.11 V across the drivers.

That puts it in the easy category. A phone, a laptop headphone jack or the cheapest USB dongle will drive it to painful levels. Of the 280 sources in the database, 277 have at least 10 dB of headroom and another 3 have enough. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.

The two numbers that decide everything

Impedance14.5 Ω
Sensitivity100.6 dB/mW
Sensitivity (voltage)119.0 dB/V
Power for 100 dB SPL0.87 mW
Voltage for 100 dB SPL0.11 V
TypeIn-ear monitor
Easy to drive — anything will do it
All 280 sources at 100 dB SPL into 14.5Ω
Comfortable 277Enough 3Marginal 0Not enough 0
Cheapest portable source that does it
$9 · USB dongle · +12 dB headroom
Cheapest desktop amp with 10 dB to spare
$75 · desktop DAC/amp · +19 dB headroom

Sensitivity here is in dB per milliwatt. Why the unit matters.

Where this sensitivity figure comes from

Moondrop publishes this as 119 dB/Vrms ((@1kHz)) — a figure per volt, not per milliwatt. At 14.5Ω the two differ by 18.4 dB, so the 100.6 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 18 dB easier to drive than it is — which is roughly the difference between a dongle being enough and not being enough.

Moondrop prints the impedance as 14.5Ω±15% (@1kHz), not as a bare number. Everything on this page is calculated with the nominal 14.5Ω, and the rest of that line is quoted here rather than tidied away, because how a figure is qualified is part of the specification too.

Source: moondroplab.com. How this data was built.

What is printed there, and what it is worth

As it is labelledAs printedToleranceStandard
Frequency Response10Hz- 24kHznot printednot printed
Effective Frequency Response20Hz - 20kHz (IEC60318-4, 3dB)3 dBIEC60318-4

Moondrop prints two frequency ranges for the Moondrop Dusk (2024). 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.

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.

Power, voltage and current by listening level

LevelWhat it isPowerVoltageCurrent
85 dB SPLquiet background listening0.03 mW20 mV1.4 mA
95 dB SPLnormal listening0.28 mW63 mV4.4 mA
100 dB SPLloud listening0.87 mW0.11 V7.8 mA
105 dB SPLvery loud2.8 mW0.20 V13.8 mA
110 dB SPLpeaks on dynamic music8.7 mW0.36 V24.5 mA

Most people listen between 75 and 85 dB; the 100 dB row leaves room for peaks.

The cheapest sources that drive them with room to spare

The 15 cheapest of the 280 sources here that reach 100 dB SPL into 14.5Ω 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.

SourceTypePricePower into 14.5ΩHeadroomVerdict
FiiO SnowSky Tiny AUSB dongle$2241 mW+17 dBComfortable
FiiO SnowSky Tiny BUSB dongle$2262 mW+18 dBComfortable
Tanchjim Stargate IIUSB dongle$4074 mW+19 dBComfortable
ddHiFi TC35ALUSB dongle$4695 mW+20 dBComfortable
ddHiFi TC35AirUSB dongle$4695 mW+20 dBComfortable
Fosi Audio N3Bluetooth receiver$5063 mW+19 dBComfortable
Hidizs SD2USB dongle$5032 mW+16 dBComfortable
FiiO BTR13Bluetooth receiver$59109 mW+21 dBComfortable
iFi GO linkUSB dongle$5932 mW+16 dBComfortable
Kiwi Ears Allegro ProUSB dongle$6031 mW+15 dBComfortable
ddHiFi TC35Pro (Mountain2)USB dongle$6629 mW+15 dBComfortable
iBasso DC03 ProUSB dongle$6944 mW+17 dBComfortable
DUNU DTC 480USB dongle$7029 mW+15 dBComfortable
EPZ TP35 ProUSB dongle$7051 mW+18 dBComfortable
Tanchjim SpaceUSB dongle$7057 mW+18 dBComfortable

The three ways a source goes wrong

Hiss. At 119.0 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 27 dB SPL in these headphones — clearly audible in quiet passages. Check your own source.

Output impedance. At 14.5Ω these want a source output impedance below 1.81Ω to satisfy the one-eighth rule; 39 of the 192 sources that publish one miss it. Check yours here.

Similar headphones

Compared with its stablemates: vs Armature Art 12 · vs Armature Art 24 · vs Quarks · vs Starfield II.

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