The Moondrop Armature Art 12 is 5Ω at 98.0 dB/mW; the Moondrop SOLIS II is 10Ω at 101.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The Armature Art 12 needs 3.0 dB more than the SOLIS II to reach the same loudness — 1.6 mW against 0.79 mW.
| Specification | Armature Art 12 | SOLIS II |
|---|---|---|
| Impedance | 5 Ω | 10 Ω |
| Sensitivity | 98.0 dB/mW | 101.0 dB/mW |
| Sensitivity (voltage) | 121.0 dB/V | 121.0 dB/V |
| Power for 100 dB | 1.6 mW | 0.79 mW |
| Voltage for 100 dB | 89 mV | 89 mV |
| Current for 100 dB | 17.8 mA | 8.9 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 0.62 Ω | 1.25 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
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.
46 sources are low enough in output impedance for the SOLIS II under the one-eighth rule but not for the Armature Art 12 (FiiO SnowSky Tiny B, FiiO KA11, JDS Labs Atom+ (2nd gen), 43 more).
280 of the 280 sources here reach 100 dB on both.
The SOLIS II is more demanding than 28% of the 567 non-electrostatic models in this database; the Armature Art 12 than 28%.
| dB SPL | Armature Art 12 power | Armature Art 12 voltage | SOLIS II power | SOLIS II voltage |
|---|---|---|---|---|
| 80 | 0.02 mW | 9 mV | 7.9 µW | 9 mV |
| 85 | 0.05 mW | 16 mV | 0.03 mW | 16 mV |
| 90 | 0.16 mW | 28 mV | 0.08 mW | 28 mV |
| 95 | 0.50 mW | 50 mV | 0.25 mW | 50 mV |
| 100 | 1.6 mW | 89 mV | 0.79 mW | 89 mV |
| 105 | 5.0 mW | 0.16 V | 2.5 mW | 0.16 V |
| Source | Price | Headroom, Armature Art 12 | Headroom, SOLIS II | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 4.7 dB | 10.7 dB | 0.5 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 9.5 dB | 15.5 dB | 0.5 Ω | 8.0 µV |
| FiiO BTR13 | $59 | 13.7 dB | 19.8 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 39 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 39 is the JadeAudio JA11, at $20. It leaves 4.7 dB of headroom on the Armature Art 12 and 10.7 dB on the SOLIS II, its output impedance is 0.5 Ω against a one-eighth limit of 0.62 Ω and 1.25 Ω, and its noise figure puts the hiss floor 14 dB and 14 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Armature Art 12 | 6Hz-34kHz | not printed | not printed |
| 20Hz-20kHz (IEC60318-4, -3dB) | -3 dB | IEC60318-4 | |
| SOLIS II | 7Hz-40kHz | not printed | not printed |
| 20Hz-20kHz (IEC60318-4, 3dB) | 3 dB | IEC60318-4 |
Moondrop prints two ranges, “6Hz-34kHz” and “20Hz-20kHz (IEC60318-4, -3dB)”, for the Armature Art 12 and two ranges, “7Hz-40kHz” and “20Hz-20kHz (IEC60318-4, 3dB)”, for the SOLIS II.
Both sheets print a tolerance, which is rare enough to be worth pointing at: only 58 of the 490 models with a printed range do. These two ranges can be set against each other, because each of them says how far down the response is allowed to be at the ends.
Not a measurement; maker by maker.
Both have a page of their own. In full: Moondrop Armature Art 12 and Moondrop SOLIS II. Every figure on this page comes from what Moondrop published, or is derived from it — what that maker publishes, counted.