The Tangzu Li Zhi is 18Ω at 107.5 dB (no reference unit printed); the Tangzu Xuan Nv is 8.5Ω at 98.0 dB (no reference unit printed). This page covers what they ask of an amplifier, not how they sound.
The Xuan Nv needs 9.5 dB more than the Li Zhi to reach the same loudness — 1.6 mW against 0.18 mW.
| Specification | Li Zhi | Xuan Nv |
|---|---|---|
| Impedance | 18 Ω | 8.5 Ω |
| Sensitivity | 107.5 dB | 98.0 dB |
| Sensitivity (voltage) | 124.9 dB/V | 118.7 dB/V |
| Power for 100 dB | 0.18 mW | 1.6 mW |
| Voltage for 100 dB | 57 mV | 0.12 V |
| Current for 100 dB | 3.1 mA | 13.7 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.25 Ω | 1.06 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. Tangzu Li Zhi and Tangzu Xuan Nv printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, each of them needs far more than the table says. Why the two readings differ by so much.
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.
12 sources are low enough in output impedance for the Li Zhi under the one-eighth rule but not for the Xuan Nv (FiiO KA13, FiiO K11, Schiit Vali 2+, 9 more).
9 sources stay below the audible-hiss threshold with the Xuan Nv but cross it with the Li Zhi (FiiO BTR11, FiiO K11 R2R, Lake People G103-S Mk II, 6 more).
280 of the 280 sources here reach 100 dB on both.
The Xuan Nv is more demanding than 38% of the 567 non-electrostatic models in this database; the Li Zhi than 16%.
| dB SPL | Li Zhi power | Li Zhi voltage | Xuan Nv power | Xuan Nv voltage |
|---|---|---|---|---|
| 80 | 1.8 µW | 6 mV | 0.02 mW | 12 mV |
| 85 | 5.6 µW | 10 mV | 0.05 mW | 21 mV |
| 90 | 0.02 mW | 18 mV | 0.16 mW | 37 mV |
| 95 | 0.06 mW | 32 mV | 0.50 mW | 65 mV |
| 100 | 0.18 mW | 57 mV | 1.6 mW | 0.12 V |
| 105 | 0.56 mW | 0.10 V | 5.0 mW | 0.21 V |
| Source | Price | Headroom, Li Zhi | Headroom, Xuan Nv | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 19.8 dB | 7.0 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 31.2 dB | 19.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 28.1 dB | 16.0 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 55 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 55 is the JadeAudio JA11, at $20. It leaves 19.8 dB of headroom on the Li Zhi and 7.0 dB on the Xuan Nv, its output impedance is 0.5 Ω against a one-eighth limit of 2.25 Ω and 1.06 Ω, and its noise figure puts the hiss floor 10 dB and 17 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Li Zhi | 20Hz-20.000kHz | not printed | not printed |
| Xuan Nv | 7Hz-20kHz | not printed | not printed |
Tangzu prints 20Hz-20.000kHz for the Li Zhi and 7Hz-20kHz for the Xuan Nv.
Li Zhi: Tangzu prints the top of the range as “20.000kHz”. As a decimal point that is 20 kHz; as a thousands separator it would be twenty megahertz. Either way the range it describes is the audible band and nothing beyond it.
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 have a page of their own. In full: Tangzu Li Zhi and Tangzu Xuan Nv. Each figure on this page is labelled on those pages with where it came from, including the ones Tangzu never published — what that maker publishes, counted.