The Hisenior Mega5EST is 25Ω at 105.0 dB/mW; the Hisenior Okavango is 20Ω at 112.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The Mega5EST needs 7.0 dB more than the Okavango to reach the same loudness — 0.32 mW against 0.06 mW.
| Specification | Mega5EST | Okavango |
|---|---|---|
| Impedance | 25 Ω | 20 Ω |
| Sensitivity | 105.0 dB/mW | 112.0 dB/mW |
| Sensitivity (voltage) | 121.0 dB/V | 129.0 dB/V |
| Power for 100 dB | 0.32 mW | 0.06 mW |
| Voltage for 100 dB | 89 mV | 36 mV |
| Current for 100 dB | 3.6 mA | 1.8 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 3.12 Ω | 2.50 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.
19 sources stay below the audible-hiss threshold with the Mega5EST but cross it with the Okavango (FiiO BTR11, Fosi Audio SK02, FiiO K11 R2R, 16 more).
280 of the 280 sources here reach 100 dB on both.
The Mega5EST is more demanding than 28% of the 567 non-electrostatic models in this database; the Okavango than 5%.
| dB SPL | Mega5EST power | Mega5EST voltage | Okavango power | Okavango voltage |
|---|---|---|---|---|
| 80 | 3.2 µW | 9 mV | 0.6 µW | 4 mV |
| 85 | 0.01 mW | 16 mV | 2.0 µW | 6 mV |
| 90 | 0.03 mW | 28 mV | 6.3 µW | 11 mV |
| 95 | 0.10 mW | 50 mV | 0.02 mW | 20 mV |
| 100 | 0.32 mW | 89 mV | 0.06 mW | 36 mV |
| 105 | 1.0 mW | 0.16 V | 0.20 mW | 63 mV |
| Source | Price | Headroom, Mega5EST | Headroom, Okavango | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 18.7 dB | 24.7 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 28.2 dB | 35.5 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 25.2 dB | 32.4 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 53 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 53 is the JadeAudio JA11, at $20. It leaves 18.7 dB of headroom on the Mega5EST and 24.7 dB on the Okavango, its output impedance is 0.5 Ω against a one-eighth limit of 3.12 Ω and 2.50 Ω, and its noise figure puts the hiss floor 14 dB and 6 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Mega5EST | 10Hz-50Khz | not printed | not printed |
| Okavango | 10Hzz-30Khz | not printed | not printed |
Hisenior prints 10Hz-50Khz for the Mega5EST and 10Hzz-30Khz for the Okavango.
Okavango: Printed as "10Hzz" with a doubled letter. Quoted here exactly as it stands on the page.
Neither range has a tolerance printed beside it, so a wider range on one sheet is not deeper bass or more treble.
Not a measurement; maker by maker.
Both have a page of their own. In full: Hisenior Mega5EST and Hisenior Okavango. Every figure on this page comes from what Hisenior published, or is derived from it — what that maker publishes, counted.