The Thieaudio Hype 4 is 17Ω at 105.0 dB (no reference unit printed); the Thieaudio Oracle MKII is 15Ω at 104.0 dB (no figure from the maker at all). 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 Oracle MKII needs 1.0 dB more than the Hype 4 to reach the same loudness — 0.40 mW against 0.32 mW.
| Specification | Hype 4 | Oracle MKII |
|---|---|---|
| Impedance | 17 Ω | 15 Ω |
| Sensitivity | 105.0 dB | 104.0 dB |
| Sensitivity (voltage) | 122.7 dB/V | 122.2 dB/V |
| Power for 100 dB | 0.32 mW | 0.40 mW |
| Voltage for 100 dB | 73 mV | 77 mV |
| Current for 100 dB | 4.3 mA | 5.2 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.12 Ω | 1.88 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. Thieaudio Hype 4 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. For Thieaudio Oracle MKII the maker publishes no sensitivity figure at all. The number in the table was collected when this database was first built and has never been traced to a manufacturer document, so treat every row below it as an estimate rather than a specification.
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 Hype 4 under the one-eighth rule but not for the Oracle MKII (Astell&Kern HC3, RME Fireface UFX II, RME Fireface UFX III).
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.
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 Oracle MKII is more demanding than 24% of the 567 non-electrostatic models in this database; the Hype 4 than 23%. 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 SPL | Hype 4 power | Hype 4 voltage | Oracle MKII power | Oracle MKII voltage |
|---|---|---|---|---|
| 80 | 3.2 µW | 7 mV | 4.0 µW | 8 mV |
| 85 | 0.01 mW | 13 mV | 0.01 mW | 14 mV |
| 90 | 0.03 mW | 23 mV | 0.04 mW | 24 mV |
| 95 | 0.10 mW | 41 mV | 0.13 mW | 43 mV |
| 100 | 0.32 mW | 73 mV | 0.40 mW | 77 mV |
| 105 | 1.0 mW | 0.13 V | 1.3 mW | 0.14 V |
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.
| Source | Price | Headroom, Hype 4 | Headroom, Oracle MKII | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 17.0 dB | 15.5 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 28.8 dB | 27.6 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 25.7 dB | 24.5 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. That is the easy axis. 67 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 67 is the JadeAudio JA11, at $20. It leaves 17.0 dB of headroom on the Hype 4 and 15.5 dB on the Oracle MKII, its output impedance is 0.5 Ω against a one-eighth limit of 2.12 Ω and 1.88 Ω, and its noise figure puts the hiss floor 13 dB and 13 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.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Hype 4 | nothing printed | — | — |
| Oracle MKII | nothing printed | — | — |
Thieaudio prints the same thing for both the Hype 4 and the Oracle MKII: nothing at all.
Oracle MKII: Thieaudio publishes a measured frequency-response graph for this model on the same page. What it does not publish is a range: there is no row of numbers to read the graph against.
There is nothing here to compare, and that is worth saying plainly rather than filling the gap with somebody else’s measurement. Of the 578 models checked against a maker document so far, 490 carry a printed range and only 58 of those print the ±dB tolerance that would make a range mean anything.
None of this is a measurement. What each maker publishes, and what it is worth, is set out in the frequency response audit.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: Thieaudio Hype 4 and Thieaudio Oracle MKII. Each figure on this page is labelled on those pages with where it came from, including the ones Thieaudio never published — what that maker publishes, counted.