The Tangzu Li Zhi is 18Ω. Its maker prints a sensitivity of 107.5 dB and never says whether that is per milliwatt or per volt, so this page reads it as per milliwatt — on that reading it needs 0.18 mW to reach 100 dB SPL, or 57 mV across the drivers. If the figure is really per volt, it needs far more.
That puts it in the easy category. A phone, a laptop headphone jack or the cheapest USB dongle will drive it to painful levels. Of the 280 sources in the database, 280 have at least 10 dB of headroom and another 0 have enough. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.
This maker printed a decibel figure and no reference unit, so the number above is shown exactly as printed. Everything below reads it as per milliwatt, which is the commoner convention on a sheet that omits the unit — if it is really per volt, this headphone is about 17 dB harder to drive than the rest of this page assumes. The converter explains the difference.
Tangzu publishes a sensitivity of 107.5 dB and does not state whether that is per milliwatt or per volt — the spec sheet simply stops at the number.
Both readings are given here so you can judge for yourself. If that 107.5 dB is per milliwatt, the figures on this page are right as they stand. If it is per volt, the real sensitivity is 90.1 dB/mW — 17 dB lower at 18Ω — and everything above understates what these need by that much. The per-milliwatt reading is the one shown, because it is the more common convention on a spec sheet that omits the unit; treat it as an indication rather than a specification.
Tangzu prints the impedance as 18 Ω ±15% @ 1000Hz, not as a bare number. Everything on this page is calculated with the nominal 18Ω, and the rest of that line is quoted here rather than tidied away, because how a figure is qualified is part of the specification too.
Source: tangzu.net. How this data was built.
| As it is labelled | As printed | Tolerance | Standard |
|---|---|---|---|
| Frequency range | 20Hz-20.000kHz | not printed | not printed |
Tangzu prints 20Hz-20.000kHz for the Tangzu Li Zhi, under the heading “Frequency range”. Source: tangzu.net.
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.
No tolerance is printed with it, so “20Hz-20.000kHz” says nothing about how loud this headphone actually is at 20 Hz.
Only what the maker printed; maker by maker.
| Level | What it is | Power | Voltage | Current |
|---|---|---|---|---|
| 85 dB SPL | quiet background listening | 0.01 mW | 10 mV | 0.6 mA |
| 95 dB SPL | normal listening | 0.06 mW | 32 mV | 1.8 mA |
| 100 dB SPL | loud listening | 0.18 mW | 57 mV | 3.1 mA |
| 105 dB SPL | very loud | 0.56 mW | 0.10 V | 5.6 mA |
| 110 dB SPL | peaks on dynamic music | 1.8 mW | 0.18 V | 9.9 mA |
Most people listen between 75 and 85 dB; the 100 dB row leaves room for peaks.
The 15 cheapest of the 280 sources here that reach 100 dB SPL into 18Ω with at least 10 dB of headroom and no known hiss or output-impedance problem with these headphones. All 280 sources, judged for these headphones.
| Source | Type | Price | Power into 18Ω | Headroom | Verdict |
|---|---|---|---|---|---|
| FiiO SnowSky Tiny A | USB dongle | $22 | 42 mW | +24 dB | Comfortable |
| FiiO SnowSky Tiny B | USB dongle | $22 | 60 mW | +25 dB | Comfortable |
| Tanchjim Stargate II | USB dongle | $40 | 79 mW | +27 dB | Comfortable |
| ddHiFi TC35AL | USB dongle | $46 | 118 mW | +28 dB | Comfortable |
| ddHiFi TC35Air | USB dongle | $46 | 118 mW | +28 dB | Comfortable |
| Fosi Audio N3 | Bluetooth receiver | $50 | 78 mW | +26 dB | Comfortable |
| Hidizs SD2 | USB dongle | $50 | 39 mW | +23 dB | Comfortable |
| iFi GO link | USB dongle | $59 | 39 mW | +23 dB | Comfortable |
| Kiwi Ears Allegro Pro | USB dongle | $60 | 38 mW | +23 dB | Comfortable |
| ddHiFi TC35Pro (Mountain2) | USB dongle | $66 | 37 mW | +23 dB | Comfortable |
| DUNU DTC 480 | USB dongle | $70 | 37 mW | +23 dB | Comfortable |
| EPZ TP35 Pro | USB dongle | $70 | 63 mW | +25 dB | Comfortable |
| Aiyima A2 Pro | desktop DAC/amp | $75 | 84 mW | +27 dB | Comfortable |
| ddHiFi TC35Pro (Eye2) | USB dongle | $76 | 37 mW | +23 dB | Comfortable |
| ddHiFi TC44 Pro E2 | USB dongle | $99 | 141 mW | +29 dB | Comfortable |
Hiss. At 124.9 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Mjolnir 3, would put its hiss at roughly 33 dB SPL in these headphones — clearly audible in quiet passages. Check your own source.
Output impedance. At 18Ω these want a source output impedance below 2.25Ω to satisfy the one-eighth rule; 35 of the 192 sources that publish one miss it. Check yours here.
16Ω · 106.0 dB · Easy
See requirements →16Ω · 100.0 dB · Easy
See requirements →22Ω · 112.0 dB · Easy
See requirements →32Ω · 110.0 dB/mW · Easy
See requirements →32Ω · 110.0 dB/mW · Easy
See requirements →32Ω · 110.0 dB/mW · Easy
See requirements →Compared with its stablemates: vs Fudu Verse 1 · vs The King Wukong · vs Tianpeng · vs Xuan Nv · vs Zetian Wu.