AudioChainsDB
Fostex

T50RP mk3

headphones

$160

Used market: $125*

Manufacturer datasheet

Specifications

3 of 7 values have a recorded source
Connector
6.3 mm (2 m) detachable cable, 6.3-to-3.5 mm adapter·
Form Factor
Over-Ear·
Is Closed Back
no·
Impedance ohms
50
Transducer Type
Planar Magnetic·
Detachable Cable
yes·
Sensitivity dB mW
92

Expert Audio Engineering Commentary

Tonal Profile

The semi-open RP that an entire modding industry was built on, and the reason to read the Japanese sheet: it is the one that states the semi-open type plainly. The mk3 ships with two Dekoni pad sets, and pads change the response of a planar more than they do on a moving-coil design, so a measurement of 'the T50RP mk3' is really a measurement of one pad choice.

What the datasheet actually says

Quoted verbatim from the manufacturer’s own page, with the date we checked it. We state what is printed, not what anyone intended by it.

Named like something else
«型式 セミオープンRPダイナミック型»

Fostex labels the RP series 'dynamic', and in the loose sense of an electrodynamic transducer that is true. But the RP diaphragm is a printed conductor on a thin polymer film suspended in a planar magnetic field — an orthodynamic design, not a moving coil in a gap. The distinction is not academic for choosing a source: a moving-coil driver has a resonant impedance peak in the bass that a high output impedance turns into a tonal shift, while a planar diaphragm presents an essentially flat 50 Ohms across the band, so a high-output-impedance source costs level but not tonal balance. We classify these as planar magnetic for that reason and note the manufacturer's own wording here.

checked 8/5/2026

* Estimated with the depreciation fallback (~78% retained value). · checked on 8/5/2026