On power: 64 of the 65 audio interfaces here reach 100 dB SPL on the Audio-Technica ATH-R70X. It needs 1.6 mW at its 470Ω, and 1 of them do not get there.
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 1 that fall short are Steinberg UR22C. The closest of them, the Steinberg UR22C, delivers 1.3 mW into 470Ω against the 1.6 mW needed — 0.9 dB short.
The cheapest one that does reach it is the Zoom AMS-22 at $100, which delivers 2.2 mW into 470Ω — 2 dB of headroom over the 1.6 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 0.05 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 Audio-Technica ATH-R70X wants a source below 58.75Ω. Of the 43 audio interfaces here that publish an output impedance, 42 are under it and 1 are not.
The furthest over is the Tascam US-2x2HR at 66Ω, which is 1× 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 98.0 dB/mW and 470Ω, the Audio-Technica ATH-R70X turns one microvolt of source noise into about -19 dB SPL — and the threshold where that stops being noticeable in a quiet room is around 20 dB SPL.
Of the 4 audio interfaces here that publish a noise figure, 4 stay below that threshold with this headphone and 0 cross it.
The remaining 61 publish no noise figure, so they cannot be placed on either side.
| Source | Price | Into 470 Ω | Headroom | Output impedance | Hiss in these |
|---|---|---|---|---|---|
| RME Babyface Pro FS | $899 | 26 mW | 12.1 dB | 10 Ω | -3 dB SPL |
| RME ADI-2 DAC FS | $1399 | 82 mW | 17.1 dB | 0.1 Ω | -12 dB SPL |
| RME ADI-2 Pro FS R | $2199 | 202 mW | 21.1 dB | 0.1 Ω | -12 dB SPL |
4 of the 65 audio interfaces here publish all three figures. 4 of those clear all three for the Audio-Technica ATH-R70X, and the cheapest is the RME Babyface Pro FS at $899.
It delivers 26 mW into 470 Ω where this headphone needs 1.6 mW for 100 dB — 12.1 dB of headroom — its output impedance of 10 Ω sits under the one-eighth ceiling of 58.75 Ω, and its 6.3 µV of noise leaves the hiss 23 dB under the 20 dB SPL threshold this site uses.
Cheapest that satisfies three published numbers is not the same as best, and the sources left out of this count are left out for want of a published figure, not for failing one. How often that happens is its own page.
| Source | Price | Into 470Ω | Output impedance | Hiss in these | Power verdict |
|---|---|---|---|---|---|
| Audient iD4 MkII | $199 | 50 mW | not published | not published | Comfortable |
| MOTU M2 | $219 | 23 mW | not published | not published | Comfortable |
| SSL 2 MkII | $229 | 26 mW | 1 Ω | not published | Comfortable |
| Tascam US-4x4HR | $249 | 17 mW | 51.5 Ω | not published | Comfortable |
| Focusrite Scarlett 4i4 4th gen | $279 | 17 mW | 11 Ω | not published | Comfortable |
| MOTU M4 | $279 | 23 mW | not published | not published | Comfortable |
| Apogee BOOM | $299 | 16 mW | 0.5 Ω | not published | Comfortable |
| PreSonus Studio 68c | $299 | 18 mW | not published | not published | Comfortable |
| SSL 2 Plus MkII | $299 | 26 mW | 1 Ω | not published | Comfortable |
| Roland BRIDGE CAST | $340 | 19 mW | 10 Ω | not published | Comfortable |
| Audient iD14 MkII | $349 | 50 mW | not published | not published | Comfortable |
| Zoom UAC-232 | $399 | 18 mW | 12 Ω | 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 Audio-Technica ATH-R70X on other categories: USB dongles · portable players · desktop amplifiers.
The Audio-Technica ATH-R70X page has every source in the database against this headphone, and the matcher takes your own numbers.