On power: 60 of the 65 audio interfaces here reach 100 dB SPL on the Sennheiser HD 600. It needs 6.6 mW at its 300Ω, and 5 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 5 that fall short are Zoom AMS-22, Steinberg IXO22, Zoom AMS-24, Steinberg UR22C, 1 more. The closest of them, the Steinberg IXO22, delivers 5.3 mW into 300Ω against the 6.6 mW needed — 1.0 dB short.
The cheapest one that does reach it is the Audient EVO 4 at $129, which delivers 11 mW into 300Ω — 2 dB of headroom over the 6.6 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 0.21 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 Sennheiser HD 600 wants a source below 37.50Ω. Of the 43 audio interfaces here that publish an output impedance, 30 are under it and 13 are not.
The furthest over is the Tascam US-2x2HR at 66Ω, which is 2× 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 91.8 dB/mW and 300Ω, the Sennheiser HD 600 turns one microvolt of source noise into about -23 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 300 Ω | Headroom | Output impedance | Hiss in these |
|---|---|---|---|---|---|
| RME Babyface Pro FS | $899 | 40 mW | 7.8 dB | 10 Ω | -7 dB SPL |
| RME ADI-2 DAC FS | $1399 | 128 mW | 12.9 dB | 0.1 Ω | -16 dB SPL |
| RME ADI-2 Pro FS R | $2199 | 317 mW | 16.8 dB | 0.1 Ω | -16 dB SPL |
4 of the 65 audio interfaces here publish all three figures. 4 of those clear all three for the Sennheiser HD 600, and the cheapest is the RME Babyface Pro FS at $899.
It delivers 40 mW into 300 Ω where this headphone needs 6.6 mW for 100 dB — 7.8 dB of headroom — its output impedance of 10 Ω sits under the one-eighth ceiling of 37.50 Ω, and its 6.3 µV of noise leaves the hiss 27 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 300Ω | Output impedance | Hiss in these | Power verdict |
|---|---|---|---|---|---|
| SSL 12 | $599 | 126 mW | 1 Ω | not published | Comfortable |
| Apogee Duet 3 | $649 | 126 mW | 0.5 Ω | not published | Comfortable |
| RME ADI-2 DAC FS | $1399 | 128 mW | 0.1 Ω | -16 dB SPL | Comfortable |
| Apogee Symphony Desktop | $1495 | 103 mW | not published | not published | Comfortable |
| RME ADI-2 Pro FS R | $2199 | 317 mW | 0.1 Ω | -16 dB SPL | Comfortable |
| RME ADI-2 Pro EX | $2499 | 370 mW | 0.1 Ω | -16 dB SPL | Comfortable |
| Merging Anubis | $2790 | 103 mW | 0.035 Ω | not published | Comfortable |
| Lynx Aurora(n) | $3499 | 138 mW | not published | not published | Comfortable |
| Audient Horizon 8P | $3500 | 140 mW | 10 Ω | not published | Comfortable |
| Audient iD48 | $1300 | 168 mW | 50 Ω | not published | Comfortable |
| Audient ORIA | $3500 | 210 mW | 50 Ω | not published | Comfortable |
| Arturia MiniFuse 1 | $149 | 24 mW | 10 Ω | 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 Sennheiser HD 600 on other categories: USB dongles · Bluetooth receivers · portable players · desktop amplifiers · desktop DAC/amps.
The Sennheiser HD 600 page has every source in the database against this headphone, and the matcher takes your own numbers.