The Focal Clear MG is 55Ω at 104.0 dB/mW; the Sennheiser HD 600 is 300Ω at 91.8 dB/mW. This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.
The Sennheiser HD 600 needs 12.2 dB more than the Focal Clear MG to reach the same loudness — 6.6 mW against 0.40 mW.
| Specification | Focal Clear MG | Sennheiser HD 600 |
|---|---|---|
| Impedance | 55 Ω | 300 Ω |
| Sensitivity | 104.0 dB/mW | 91.8 dB/mW |
| Sensitivity (voltage) | 116.6 dB/V | 97.0 dB/V |
| Power for 100 dB | 0.40 mW | 6.6 mW |
| Voltage for 100 dB | 0.15 V | 1.41 V |
| Current for 100 dB | 2.7 mA | 4.7 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 6.88 Ω | 37.50 Ω |
| Sources that reach 100 dB out of 280 | 280 | 261 |
19 of the 280 sources have the power for the Focal Clear MG but not for the Sennheiser HD 600 — Apple USB-C dongle (US), Apple USB-C dongle (EU), JadeAudio JA11, 16 more.
19 sources are low enough in output impedance for the Sennheiser HD 600 under the one-eighth rule but not for the Focal Clear MG (Zoom AMS-22, Arturia MiniFuse 2, Arturia MiniFuse 1, 16 more).
1 source stays below the audible-hiss threshold with the Sennheiser HD 600 but crosses it with the Focal Clear MG (Schiit Mjolnir 3).
261 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.
The gap between these two in decibels does not change with volume — it is a property of the two headphones. What changes is the size of the numbers, and it changes fast: every 10 dB costs ten times the power. The row that matters is the one nearest the level you listen at, and for most people that is nearer the top of this table than the bottom.
The Sennheiser HD 600 is more demanding than 99% of the 567 non-electrostatic models in this database; the Focal Clear MG than 46%. Both figures use the same measure as the rest of the site: whichever runs out first against a 2 V, 100 mW dongle, voltage or power.
| dB SPL | Focal Clear MG power | Focal Clear MG voltage | Sennheiser HD 600 power | Sennheiser HD 600 voltage |
|---|---|---|---|---|
| 80 | 4.0 µW | 15 mV | 0.07 mW | 0.14 V |
| 85 | 0.01 mW | 26 mV | 0.21 mW | 0.25 V |
| 90 | 0.04 mW | 47 mV | 0.66 mW | 0.45 V |
| 95 | 0.13 mW | 83 mV | 2.1 mW | 0.79 V |
| 100 | 0.40 mW | 0.15 V | 6.6 mW | 1.41 V |
| 105 | 1.3 mW | 0.26 V | 21 mW | 2.50 V |
105 dB is included because forum power figures are usually quoted there or higher. It is also a level that damages hearing in minutes — how many minutes is its own calculator.
| Source | Price | Headroom, Focal Clear MG | Headroom, Sennheiser HD 600 | Output impedance | Noise |
|---|---|---|---|---|---|
| FiiO KA11 | $29 | 24.7 dB | 5.2 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 21.6 dB | 1.8 dB | 0.6 Ω | 1.0 µV |
| iBasso DC03 Pro | $69 | 21.6 dB | 2.0 dB | 0.12 Ω | 0.9 µV |
Of the 280 sources here, 261 reach 100 dB on both. That is the easy axis. 66 of them also publish an output impedance low enough for both under the one-eighth rule and a noise figure that stays below the audible-hiss threshold with both — the rest either fail one of those or never printed the number at all, and 192 of them are in the second group.
The cheapest of the 66 is the FiiO KA11, at $29. It leaves 24.7 dB of headroom on the Focal Clear MG and 5.2 dB on the Sennheiser HD 600, its output impedance is 0.7 Ω against a one-eighth limit of 6.88 Ω and 37.50 Ω, and its noise figure puts the hiss floor 19 dB and 38 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
Cheapest that satisfies three published numbers is not the same as best, and none of it is about how either headphone sounds. To put either model against a source this page does not mention, or to change the target loudness, use the amplifier matcher.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Focal Clear MG | 5Hz – 28kHz | not printed | not printed |
| Sennheiser HD 600 | 12 Hz - 40,500 Hz | not printed | not printed |
Focal prints 5Hz – 28kHz for the Clear MG. Sennheiser prints 12 Hz - 40,500 Hz for the HD 600.
Neither range has a tolerance printed beside it, and that is the whole of what this section can tell you. A wider range on one sheet is not deeper bass or more treble on that headphone: without a tolerance, neither number says how loud either model is at the ends of its own range, so the difference between the two is a difference between two pieces of marketing copy. A ±dB figure is what turns a range into a specification, and of the 490 models whose maker prints a range, 58 print it.
None of this is a measurement. What each maker publishes, and what it is worth, is set out in the frequency response audit.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: Focal Clear MG and Sennheiser HD 600. Every figure on this page comes from what Focal and Sennheiser published, or is derived from it — what Focal publishes and what Sennheiser publishes, both counted.