Ocean vs Volur: which needs more amplifier?

The 64 Audio Ocean is 9.5Ω at 103.7 dB/mW; the 64 Audio Volur is 6.3Ω at 103.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.

The Volur needs 0.7 dB more than the Ocean to reach the same loudness — 0.50 mW against 0.43 mW.

The numbers that decide it

SpecificationOceanVolur
Impedance9.5 Ω6.3 Ω
Sensitivity103.7 dB/mW103.0 dB/mW
Sensitivity (voltage)123.9 dB/V125.0 dB/V
Power for 100 dB0.43 mW0.50 mW
Voltage for 100 dB64 mV56 mV
Current for 100 dB6.7 mA8.9 mA
Highest source impedance
that leaves them alone (one-eighth rule)
1.19 Ω0.79 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.

38 sources are low enough in output impedance for the Ocean under the one-eighth rule but not for the Volur (FiiO SnowSky Tiny B, FiiO KA15, FiiO BTR15, 35 more).

5 sources stay below the audible-hiss threshold with the Ocean but cross it with the Volur (Lake People G103-S Mk II, Schiit Valhalla 3, RME Babyface Pro FS, 2 more).

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

What each one needs from 80 to 105 dB

The Ocean is more demanding than 19% of the 567 non-electrostatic models in this database; the Volur than 14%.

dB SPLOcean powerOcean voltageVolur powerVolur voltage
804.3 µW6 mV5.0 µW6 mV
850.01 mW11 mV0.02 mW10 mV
900.04 mW20 mV0.05 mW18 mV
950.13 mW36 mV0.16 mW32 mV
1000.43 mW64 mV0.50 mW56 mV
1051.3 mW0.11 V1.6 mW100 mV

The cheapest source that satisfies both

SourcePriceHeadroom, OceanHeadroom, VolurOutput impedanceNoise
JadeAudio JA11$2013.2 dB10.7 dB0.5 Ω1.7 µV
FiiO KA11$2925.3 dB22.8 dB0.7 Ω1.7 µV
FiiO BTR13$5922.2 dB19.7 dB0.6 Ω1.0 µV

Of the 280 sources here, 280 reach 100 dB on both. 37 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 37 is the JadeAudio JA11, at $20. It leaves 13.2 dB of headroom on the Ocean and 10.7 dB on the Volur, its output impedance is 0.5 Ω against a one-eighth limit of 1.19 Ω and 0.79 Ω, and its noise figure puts the hiss floor 11 dB and 10 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
Ocean5 Hz – 22 kHznot printednot printed
Volur5hz – 22kHznot printednot printed

64 Audio prints 5 Hz – 22 kHz for the Ocean and 5hz – 22kHz for the Volur.

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: 64 Audio Ocean and 64 Audio Volur. Every figure on this page comes from what 64 Audio published, or is derived from it — what that maker publishes, counted.

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