On power: 32 of the 34 desktop DAC/amps here reach 100 dB SPL on the Sennheiser HD 600. It needs 6.6 mW at its 300Ω, and 2 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 2 that fall short are WiiM Ultra, Marantz SACD 30n. The closest of them, the WiiM Ultra, delivers 6.0 mW into 300Ω against the 6.6 mW needed — 0.4 dB short.
The cheapest one that does reach it is the Aiyima A2 Pro at $75, which delivers 16 mW into 300Ω — 4 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 19 desktop DAC/amps here that publish an output impedance, 19 are under it and 0 are not.
The other 15 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 12 desktop DAC/amps here that publish a noise figure, 12 stay below that threshold with this headphone and 0 cross it.
The remaining 22 publish no noise figure, so they cannot be placed on either side.
| Source | Price | Into 300 Ω | Headroom | Output impedance | Hiss in these |
|---|---|---|---|---|---|
| FiiO K11 | $143 | 60 mW | 9.6 dB | 1.2 Ω | -14 dB SPL |
| FiiO K11 R2R | $176 | 50 mW | 8.8 dB | 1.0 Ω | -6 dB SPL |
| FiiO K7 | $199 | 140 mW | 13.3 dB | 1.0 Ω | -13 dB SPL |
11 of the 34 desktop DAC/amps here publish all three figures. 11 of those clear all three for the Sennheiser HD 600, and the cheapest is the FiiO K11 at $143.
It delivers 60 mW into 300 Ω where this headphone needs 6.6 mW for 100 dB — 9.6 dB of headroom — its output impedance of 1.2 Ω sits under the one-eighth ceiling of 37.50 Ω, and its 2.8 µV of noise leaves the hiss 34 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 |
|---|---|---|---|---|---|
| FiiO K7 | $199 | 140 mW | 1 Ω | -13 dB SPL | Comfortable |
| SMSL C200 | $219 | 139 mW | not published | not published | Comfortable |
| JDS Labs Element III MK2 | $449 | 292 mW | 0.7 Ω | -15 dB SPL | Comfortable |
| Topping DX5 | $449 | 250 mW | 0.1 Ω | not published | Comfortable |
| xDuoo XA-10 | $449 | 320 mW | not published | not published | Comfortable |
| HiFiMAN EF500 | $459 | 141 mW | not published | not published | Comfortable |
| SMSL DO400 | $520 | 700 mW | <0.1 Ω | not published | Comfortable |
| JDS Labs Element IV | $549 | 347 mW | 1 Ω | -17 dB SPL | Comfortable |
| FiiO K9 Pro | $799 | 278 mW | 1 Ω | -17 dB SPL | Comfortable |
| HiFiMAN EF600 | $799 | 192 mW | not published | not published | Comfortable |
| FiiO K17 | $990 | 240 mW | 1 Ω | -9 dB SPL | Comfortable |
| FiiO K19 | $1430 | 270 mW | 0.6 Ω | -12 dB SPL | 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 Sennheiser HD 600 on other categories: USB dongles · Bluetooth receivers · portable players · desktop amplifiers · audio interfaces.
The Sennheiser HD 600 page has every source in the database against this headphone, and the matcher takes your own numbers.