The HiFiMAN Ananda Nano is 14Ω at 94.0 dB (no reference unit printed); the Meze 99 Classics is 32Ω at 103.0 dB/mW. 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 HiFiMAN Ananda Nano needs 9.0 dB more than the Meze 99 Classics to reach the same loudness — 4.0 mW against 0.50 mW.
| Specification | HiFiMAN Ananda Nano | Meze 99 Classics |
|---|---|---|
| Impedance | 14 Ω | 32 Ω |
| Sensitivity | 94.0 dB | 103.0 dB/mW |
| Sensitivity (voltage) | 112.5 dB/V | 117.9 dB/V |
| Power for 100 dB | 4.0 mW | 0.50 mW |
| Voltage for 100 dB | 0.24 V | 0.13 V |
| Current for 100 dB | 16.9 mA | 4.0 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 1.75 Ω | 4.00 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. HiFiMAN Ananda Nano 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.
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.
4 sources are low enough in output impedance for the Meze 99 Classics under the one-eighth rule but not for the HiFiMAN Ananda Nano (Schiit Vali 2+, Astell&Kern HC3, RME Fireface UFX II, 1 more).
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.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: HiFiMAN Ananda Nano and Meze 99 Classics. Each figure on this page is labelled on those pages with where it came from, including the ones HiFiMAN and Meze never published — what HiFiMAN publishes and what Meze publishes, both counted.