On power: 45 of the 65 audio interfaces here reach 100 dB SPL on the HiFiMAN Susvara. It needs 50 mW at its 60Ω, and 20 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 20 that fall short are Zoom AMS-22, Steinberg IXO22, Audient EVO 4, IK Multimedia AXE I/O ONE, 16 more. The closest of them, the PreSonus Studio 24c, delivers 44 mW into 60Ω against the 50 mW needed — 0.6 dB short.
The cheapest one that does reach it is the Arturia MiniFuse 1 at $149, which delivers 83 mW into 60Ω — 2 dB of headroom over the 50 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 1.6 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 HiFiMAN Susvara wants a source below 7.50Ω. 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 9× 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 83.0 dB and 60Ω, the HiFiMAN Susvara turns one microvolt of source noise into about -25 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 60 Ω | Headroom | Output impedance | Hiss in these |
|---|---|---|---|---|---|
| RME ADI-2 DAC FS | $1399 | 640 mW | 11.1 dB | 0.1 Ω | -18 dB SPL |
| RME ADI-2 Pro FS R | $2199 | 1.6 W | 15.0 dB | 0.1 Ω | -18 dB SPL |
| RME ADI-2 Pro EX | $2499 | 1.1 W | 13.4 dB | 0.1 Ω | -18 dB SPL |
4 of the 65 audio interfaces here publish all three figures. 3 of those clear all three for the HiFiMAN Susvara, and the cheapest is the RME ADI-2 DAC FS at $1399.
It delivers 640 mW into 60 Ω where this headphone needs 50 mW for 100 dB — 11.1 dB of headroom — its output impedance of 0.1 Ω sits under the one-eighth ceiling of 7.50 Ω, and its 2.18 µV of noise leaves the hiss 38 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 60Ω | Output impedance | Hiss in these | Power verdict |
|---|---|---|---|---|---|
| SSL 12 | $599 | 631 mW | 1 Ω | not published | Comfortable |
| Apogee Duet 3 | $649 | 631 mW | 0.5 Ω | not published | Comfortable |
| RME ADI-2 DAC FS | $1399 | 640 mW | 0.1 Ω | -18 dB SPL | Comfortable |
| RME ADI-2 Pro FS R | $2199 | 1.6 W | 0.1 Ω | -18 dB SPL | Comfortable |
| RME ADI-2 Pro EX | $2499 | 1.1 W | 0.1 Ω | -18 dB SPL | Comfortable |
| Merging Anubis | $2790 | 513 mW | 0.035 Ω | not published | Comfortable |
| Lynx Aurora(n) | $3499 | 692 mW | not published | not published | Comfortable |
| Audient iD48 | $1300 | 565 mW | 50 Ω | not published | Comfortable |
| Audient Horizon 8P | $3500 | 691 mW | 10 Ω | not published | Comfortable |
| Audient ORIA | $3500 | 912 mW | 50 Ω | not published | Comfortable |
| Audient iD4 MkII | $199 | 138 mW | not published | not published | Enough |
| MOTU M2 | $219 | 178 mW | not published | not published | Enough |
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 HiFiMAN Susvara on other categories: USB dongles · Bluetooth receivers · portable players · desktop amplifiers · desktop DAC/amps.
The HiFiMAN Susvara page has every source in the database against this headphone, and the matcher takes your own numbers.