FOLA vs SODA: which needs more amplifier?

The Tanchjim FOLA is 16Ω at 108.0 dB/mW; the Tanchjim SODA is 15.5Ω at 101.9 dB/mW. This page covers what they ask of an amplifier, not how they sound.

The SODA needs 6.1 dB more than the FOLA to reach the same loudness — 0.65 mW against 0.16 mW.

The numbers that decide it

SpecificationFOLASODA
Impedance16 Ω15.5 Ω
Sensitivity108.0 dB/mW101.9 dB/mW
Sensitivity (voltage)126.0 dB/V120.0 dB/V
Power for 100 dB0.16 mW0.65 mW
Voltage for 100 dB50 mV0.10 V
Current for 100 dB3.1 mA6.5 mA
Highest source impedance
that leaves them alone (one-eighth rule)
2.00 Ω1.94 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.

3 sources are low enough in output impedance for the FOLA under the one-eighth rule but not for the SODA (Astell&Kern HC3, RME Fireface UFX II, RME Fireface UFX III).

14 sources stay below the audible-hiss threshold with the SODA but cross it with the FOLA (FiiO BTR11, FiiO K11 R2R, Lake People G103-S Mk II, 11 more).

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

What each one needs from 80 to 105 dB

The SODA is more demanding than 32% of the 567 non-electrostatic models in this database; the FOLA than 11%.

dB SPLFOLA powerFOLA voltageSODA powerSODA voltage
801.6 µW5 mV6.5 µW10 mV
855.0 µW9 mV0.02 mW18 mV
900.02 mW16 mV0.06 mW32 mV
950.05 mW28 mV0.20 mW56 mV
1000.16 mW50 mV0.65 mW0.10 V
1050.50 mW90 mV2.0 mW0.18 V

The cheapest source that satisfies both

SourcePriceHeadroom, FOLAHeadroom, SODAOutput impedanceNoise
JadeAudio JA11$2019.8 dB13.5 dB0.5 Ω1.7 µV
FiiO KA11$2931.9 dB25.7 dB0.7 Ω1.7 µV
FiiO BTR13$5928.8 dB22.6 dB0.6 Ω1.0 µV

Of the 280 sources here, 280 reach 100 dB on both. 57 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 57 is the JadeAudio JA11, at $20. It leaves 19.8 dB of headroom on the FOLA and 13.5 dB on the SODA, its output impedance is 0.5 Ω against a one-eighth limit of 2.00 Ω and 1.94 Ω, and its noise figure puts the hiss floor 9 dB and 15 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
FOLA2-48 kHZnot printednot printed
SODA8-48 kHZnot printednot printed

Tanchjim prints 2-48 kHZ for the FOLA and 8-48 kHZ for the SODA.

FOLA: Tanchjim prints this row in Chinese and puts the unit only on the upper figure, so the lower number carries no unit of its own.

SODA: Tanchjim prints this row in Chinese and puts the unit only on the upper figure. Read strictly, “8-48 kHZ” starts at 8 kHz; read the way everyone reads it, at 8 Hz. The maker does not say which.

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: Tanchjim FOLA and Tanchjim SODA. Every figure on this page comes from what Tanchjim published, or is derived from it — what that maker publishes, counted.

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