On power, yes — all of them. Every one of the 65 audio interfaces in this database reaches 100 dB SPL on the Fostex T50RP MK3, which needs 6.3 mW at its 50Ω.
Power is one of three questions and the one that goes wrong least often. The other two — whether the source’s output impedance leaves the frequency response alone, and whether you will hear its noise floor — are answered further down, separately, because a source can pass one and fail another.
The cheapest one that does reach it is the Zoom AMS-22 at $100, which delivers 14 mW into 50Ω — 3 dB of headroom over the 6.3 mW this headphone needs for 100 dB SPL.
100 dB SPL is a peak level, not a listening level. If you listen at 85 dB the same headphone needs 0.20 mW, which is 15 dB less, and the answer above changes for most of the category. The model page has the full ladder.
Under the one-eighth rule the Fostex T50RP MK3 wants a source below 6.25Ω. Of the 43 audio interfaces here that publish an output impedance, 15 are under it and 28 are not.
The furthest over is the Tascam US-2x2HR at 66Ω, which is 11× the ceiling. Above that threshold the source stops being a volume control and starts being part of the frequency response. The simulator shows what that looks like.
The other 22 publish nothing at all on this, so they are not on either side of that count. This site leaves them blank rather than assuming a figure.
Hiss depends on the source’s own noise floor and on how sensitive the headphone is. At 92.0 dB/mW and 50Ω, the Fostex T50RP MK3 turns one microvolt of source noise into about -15 dB SPL — and the threshold where that stops being noticeable in a quiet room is around 20 dB SPL.
The one audio interface here that publishes a noise figure stays below that threshold with this headphone.
The remaining 64 publish no noise figure, so they cannot be placed on either side.
| Source | Price | Into 50Ω | Output impedance | Hiss in these | Power verdict |
|---|---|---|---|---|---|
| Steinberg UR24C | $194 | 80 mW | not published | not published | Comfortable |
| Audient iD4 MkII | $199 | 128 mW | not published | not published | Comfortable |
| PreSonus Quantum ES 2 | $199 | 68 mW | not published | not published | Comfortable |
| MOTU M2 | $219 | 213 mW | not published | not published | Comfortable |
| SSL 2 MkII | $229 | 239 mW | 1 Ω | not published | Comfortable |
| MOTU M4 | $279 | 213 mW | not published | not published | Comfortable |
| Apogee BOOM | $299 | 154 mW | 0.5 Ω | not published | Comfortable |
| PreSonus Studio 68c | $299 | 134 mW | not published | not published | Comfortable |
| SSL 2 Plus MkII | $299 | 239 mW | 1 Ω | not published | Comfortable |
| M-Audio AIR 192|14 | $329 | 102 mW | not published | not published | Comfortable |
| Audient iD14 MkII | $349 | 128 mW | not published | not published | Comfortable |
| Steinberg UR44C | $349 | 80 mW | not published | not published | Comfortable |
Sorted by how many of the three questions the source answers well, then by price. A blank in a column is a blank in the manufacturer’s own documentation, not a zero.
The Fostex T50RP MK3 on other categories: desktop amplifiers · desktop DAC/amps.
The Fostex T50RP MK3 page has every source in the database against this headphone, and the matcher takes your own numbers.