Orchestra II vs Stardust: which needs more amplifier?

The Kiwi Ears Orchestra II is 15Ω at 110.0 dB/mW; the Kiwi Ears Stardust is 13Ω at 107.0 dB (no reference unit printed). This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.

The Stardust needs 3.0 dB more than the Orchestra II to reach the same loudness — 0.20 mW against 0.10 mW.

The numbers that decide it

SpecificationOrchestra IIStardust
Impedance15 Ω13 Ω
Sensitivity110.0 dB/mW107.0 dB
Sensitivity (voltage)128.2 dB/V125.9 dB/V
Power for 100 dB0.10 mW0.20 mW
Voltage for 100 dB39 mV51 mV
Current for 100 dB2.6 mA3.9 mA
Highest source impedance
that leaves them alone (one-eighth rule)
1.88 Ω1.62 Ω
Sources that reach 100 dB
out of 280
280280

One caution before reading the rows. Kiwi Ears Stardust printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, that model needs far more than the table says. Why the two readings differ by so much.

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.

2 sources are low enough in output impedance for the Orchestra II under the one-eighth rule but not for the Stardust (FiiO KA13, Schiit Vali 2+).

4 sources stay below the audible-hiss threshold with the Stardust but cross it with the Orchestra II (Grace Design m900, Schiit Lyr 5, FiiO K17, 1 more).

280 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.

What each one needs from 80 to 105 dB

The gap between these two in decibels does not change with volume — it is a property of the two headphones. What changes is the size of the numbers, and it changes fast: every 10 dB costs ten times the power. The row that matters is the one nearest the level you listen at, and for most people that is nearer the top of this table than the bottom.

The Stardust is more demanding than 12% of the 567 non-electrostatic models in this database; the Orchestra II than 6%. Both figures use the same measure as the rest of the site: whichever runs out first against a 2 V, 100 mW dongle, voltage or power.

dB SPLOrchestra II powerOrchestra II voltageStardust powerStardust voltage
801.0 µW4 mV2.0 µW5 mV
853.2 µW7 mV6.3 µW9 mV
900.01 mW12 mV0.02 mW16 mV
950.03 mW22 mV0.06 mW29 mV
1000.10 mW39 mV0.20 mW51 mV
1050.32 mW69 mV0.63 mW91 mV

105 dB is included because forum power figures are usually quoted there or higher. It is also a level that damages hearing in minutes — how many minutes is its own calculator.

The cheapest source that satisfies both

SourcePriceHeadroom, Orchestra IIHeadroom, StardustOutput impedanceNoise
JadeAudio JA11$2021.5 dB17.9 dB0.5 Ω1.7 µV
FiiO KA11$2933.6 dB30.0 dB0.7 Ω1.7 µV
FiiO BTR13$5930.5 dB26.9 dB0.6 Ω1.0 µV

Of the 280 sources here, 280 reach 100 dB on both. That is the easy axis. 52 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 rest either fail one of those or never printed the number at all, and 208 of them are in the second group.

The cheapest of the 52 is the JadeAudio JA11, at $20. It leaves 21.5 dB of headroom on the Orchestra II and 17.9 dB on the Stardust, its output impedance is 0.5 Ω against a one-eighth limit of 1.88 Ω and 1.62 Ω, and its noise figure puts the hiss floor 7 dB and 10 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.

Cheapest that satisfies three published numbers is not the same as best, and none of it is about how either headphone sounds. To put either model against a source this page does not mention, or to change the target loudness, use the amplifier matcher.

What each sheet prints, and what it is worth

ModelAs printedToleranceStandard
Orchestra II20Hz-20KHznot printednot printed
Stardust20Hz–40kHznot printednot printed

Kiwi Ears prints 20Hz-20KHz for the Orchestra II and 20Hz–40kHz for the Stardust.

Neither range has a tolerance printed beside it, and that is the whole of what this section can tell you. A wider range on one sheet is not deeper bass or more treble on that headphone: without a tolerance, neither number says how loud either model is at the ends of its own range, so the difference between the two is a difference between two pieces of marketing copy. A ±dB figure is what turns a range into a specification, and of the 490 models whose maker prints a range, 58 print it.

None of this is a measurement. What each maker publishes, and what it is worth, is set out in the frequency response audit.

Both pages in full

Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: Kiwi Ears Orchestra II and Kiwi Ears Stardust. Each figure on this page is labelled on those pages with where it came from, including the ones Kiwi Ears never published — what that maker publishes, counted.

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