The Dan Clark Audio Ether C Flow 1.1 is 23Ω at 94.0 dB (no figure from the maker at all); the Dan Clark Audio Noire X is 13Ω at 90.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The Noire X needs 4.0 dB more than the Ether C Flow 1.1 to reach the same loudness — 10 mW against 4.0 mW.
| Specification | Ether C Flow 1.1 | Noire X |
|---|---|---|
| Impedance | 23 Ω | 13 Ω |
| Sensitivity | 94.0 dB | 90.0 dB/mW |
| Sensitivity (voltage) | 110.4 dB/V | 108.9 dB/V |
| Power for 100 dB | 4.0 mW | 10 mW |
| Voltage for 100 dB | 0.30 V | 0.36 V |
| Current for 100 dB | 13.2 mA | 27.7 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.88 Ω | 1.62 Ω |
| Sources that reach 100 dB out of 280 | 280 | 272 |
One caution before reading the rows. For Dan Clark Audio Ether C Flow 1.1 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.
8 of the 280 sources have the power for the Ether C Flow 1.1 but not for the Noire X — Apple USB-C dongle (EU), Zoom AMS-22, Audient EVO 4, 5 more.
5 sources are low enough in output impedance for the Ether C Flow 1.1 under the one-eighth rule but not for the Noire X (FiiO KA13, Schiit Vali 2+, Astell&Kern HC3, 2 more).
272 of the 280 sources here reach 100 dB on both.
The Noire X is more demanding than 80% of the 567 non-electrostatic models in this database; the Ether C Flow 1.1 than 75%.
| dB SPL | Ether C Flow 1.1 power | Ether C Flow 1.1 voltage | Noire X power | Noire X voltage |
|---|---|---|---|---|
| 80 | 0.04 mW | 30 mV | 0.10 mW | 36 mV |
| 85 | 0.13 mW | 54 mV | 0.32 mW | 64 mV |
| 90 | 0.40 mW | 96 mV | 1.0 mW | 0.11 V |
| 95 | 1.3 mW | 0.17 V | 3.2 mW | 0.20 V |
| 100 | 4.0 mW | 0.30 V | 10 mW | 0.36 V |
| 105 | 13 mW | 0.54 V | 32 mW | 0.64 V |
| Source | Price | Headroom, Ether C Flow 1.1 | Headroom, Noire X | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 7.3 dB | 0.9 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 17.3 dB | 13.0 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 9.5 dB | 5.6 dB | 0.5 Ω | 8.0 µV |
Of the 280 sources here, 272 reach 100 dB on both. 69 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 69 is the JadeAudio JA11, at $20. It leaves 7.3 dB of headroom on the Ether C Flow 1.1 and 0.9 dB on the Noire X, its output impedance is 0.5 Ω against a one-eighth limit of 2.88 Ω and 1.62 Ω, and its noise figure puts the hiss floor 25 dB and 27 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
Both have a page of their own. In full: Dan Clark Audio Ether C Flow 1.1 and Dan Clark Audio Noire X. Each figure on this page is labelled on those pages with where it came from, including the ones Dan Clark Audio never published — what that maker publishes, counted.