The Hidizs MP143 Salt is 17Ω at 103.0 dB (no reference unit printed); the Hidizs MS2 PRO is 17Ω at 111.0 dB (no reference unit printed). This page covers what they ask of an amplifier, not how they sound.
The MP143 Salt needs 8.0 dB more than the MS2 PRO to reach the same loudness — 0.50 mW against 0.08 mW.
| Specification | MP143 Salt | MS2 PRO |
|---|---|---|
| Impedance | 17 Ω | 17 Ω |
| Sensitivity | 103.0 dB | 111.0 dB |
| Sensitivity (voltage) | 120.7 dB/V | 128.7 dB/V |
| Power for 100 dB | 0.50 mW | 0.08 mW |
| Voltage for 100 dB | 92 mV | 37 mV |
| Current for 100 dB | 5.4 mA | 2.2 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.12 Ω | 2.12 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. Hidizs MP143 Salt and Hidizs MS2 PRO printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, each of them 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.
19 sources stay below the audible-hiss threshold with the MP143 Salt but cross it with the MS2 PRO (FiiO BTR11, Fosi Audio SK02, FiiO K11 R2R, 16 more).
280 of the 280 sources here reach 100 dB on both.
The MP143 Salt is more demanding than 30% of the 567 non-electrostatic models in this database; the MS2 PRO than 5%.
| dB SPL | MP143 Salt power | MP143 Salt voltage | MS2 PRO power | MS2 PRO voltage |
|---|---|---|---|---|
| 80 | 5.0 µW | 9 mV | 0.8 µW | 4 mV |
| 85 | 0.02 mW | 16 mV | 2.5 µW | 7 mV |
| 90 | 0.05 mW | 29 mV | 7.9 µW | 12 mV |
| 95 | 0.16 mW | 52 mV | 0.03 mW | 21 mV |
| 100 | 0.50 mW | 92 mV | 0.08 mW | 37 mV |
| 105 | 1.6 mW | 0.16 V | 0.25 mW | 65 mV |
| Source | Price | Headroom, MP143 Salt | Headroom, MS2 PRO | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 15.0 dB | 23.0 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 26.8 dB | 34.8 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 23.7 dB | 31.7 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 15.0 dB of headroom on the MP143 Salt and 23.0 dB on the MS2 PRO, its output impedance is 0.5 Ω against a one-eighth limit of 2.12 Ω for both, and its noise figure puts the hiss floor 15 dB and 7 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| MP143 Salt | 20Hz to 40kHz | not printed | not printed |
| MS2 PRO | nothing printed | — | — |
Hidizs prints 20Hz to 40kHz for the MP143 Salt and nothing at all for the MS2 PRO.
MP143 Salt: Hidizs prints this figure in the body copy of the product page. The only specification table on that page belongs to a different product — one of the company’s DAC dongles — and there is no frequency row in a table for this model.
MS2 PRO: The page does carry a specification table with a frequency-response row — but that table is for one of the company’s DAC dongles, not for these in-ears.
So one side of this comparison has a frequency-response number and the other does not — which changes less than it looks. The range printed for the MP143 Salt comes with no tolerance beside it, and a range without a ±dB figure says nothing about how loud the headphone is at either end of it: thirty decibels down at the bottom and the sentence would still be true. On the only reading that would have made it a specification, the two sheets say the same amount: nothing.
Not a measurement; maker by maker.
Both have a page of their own. In full: Hidizs MP143 Salt and Hidizs MS2 PRO. Each figure on this page is labelled on those pages with where it came from, including the ones Hidizs never published — what that maker publishes, counted.