ATH-M70X vs ATH-WP900: which needs more amplifier?

The Audio-Technica ATH-M70X is 35Ω at 97.0 dB/mW; the Audio-Technica ATH-WP900 is 38Ω at 100.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.

The ATH-M70X needs 3.0 dB more than the ATH-WP900 to reach the same loudness — 2.0 mW against 1.0 mW.

The numbers that decide it

SpecificationATH-M70XATH-WP900
Impedance35 Ω38 Ω
Sensitivity97.0 dB/mW100.0 dB/mW
Sensitivity (voltage)111.6 dB/V114.2 dB/V
Power for 100 dB2.0 mW1.0 mW
Voltage for 100 dB0.26 V0.19 V
Current for 100 dB7.6 mA5.1 mA
Highest source impedance
that leaves them alone (one-eighth rule)
4.38 Ω4.75 Ω
Sources that reach 100 dB
out of 280
280280

Where the two part company

Every source in the database that drives one of them drives the other. On power, the choice between these two changes nothing about what amplifier you need.

1 source is low enough in output impedance for the ATH-WP900 under the one-eighth rule but not for the ATH-M70X (Shanling H5).

1 source stays below the audible-hiss threshold with the ATH-M70X but crosses it with the ATH-WP900 (Schiit Mjolnir 3).

280 of the 280 sources here reach 100 dB on both.

What each one needs from 80 to 105 dB

The ATH-M70X is more demanding than 69% of the 567 non-electrostatic models in this database; the ATH-WP900 than 57%.

dB SPLATH-M70X powerATH-M70X voltageATH-WP900 powerATH-WP900 voltage
800.02 mW26 mV0.01 mW19 mV
850.06 mW47 mV0.03 mW35 mV
900.20 mW84 mV0.10 mW62 mV
950.63 mW0.15 V0.32 mW0.11 V
1002.0 mW0.26 V1.0 mW0.19 V
1056.3 mW0.47 V3.2 mW0.35 V

The cheapest source that satisfies both

SourcePriceHeadroom, ATH-M70XHeadroom, ATH-WP900Output impedanceNoise
JadeAudio JA11$2011.4 dB14.0 dB0.5 Ω1.7 µV
FiiO KA11$2919.6 dB22.3 dB0.7 Ω1.7 µV
FiiO BTR11$3611.4 dB14.0 dB0.5 Ω8.0 µV

Of the 280 sources here, 280 reach 100 dB on both. 69 of them also publish an output impedance low enough for both under the one-eighth rule and a noise figure that stays below the audible-hiss threshold with both.

The cheapest of the 69 is the JadeAudio JA11, at $20. It leaves 11.4 dB of headroom on the ATH-M70X and 14.0 dB on the ATH-WP900, its output impedance is 0.5 Ω against a one-eighth limit of 4.38 Ω and 4.75 Ω, and its noise figure puts the hiss floor 24 dB and 21 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.

Try any other source.

What each sheet prints, and what it is worth

ModelAs printedToleranceStandard
ATH-M70X5 - 40,000 Hznot printednot printed
ATH-WP9005 – 50,000 Hznot printednot printed

Audio-Technica prints 5 - 40,000 Hz for the ATH-M70X and 5 – 50,000 Hz for the ATH-WP900.

Neither range has a tolerance printed beside it, so a wider range on one sheet is not deeper bass or more treble.

Not a measurement; maker by maker.

Both pages in full

Both have a page of their own. In full: Audio-Technica ATH-M70X and Audio-Technica ATH-WP900. Every figure on this page comes from what Audio-Technica published, or is derived from it — what that maker publishes, counted.

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