The Shure SE846 is 9Ω with a sensitivity of 114.0 dB/mW, which is 134.5 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 0.04 mW, or 19 mV across the drivers.
That puts it in the easy category. A phone, a laptop headphone jack or the cheapest USB dongle will drive it to painful levels. Of the 53 sources in the database, 53 have comfortable headroom. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.
Sensitivity here is in dB per milliwatt. Manufacturers often quote dB per volt instead and leave the unit off, which is the single most common reason online calculators give answers that are 10–15 dB wrong. The converter explains the difference.
| Level | What it is | Power | Voltage | Current |
|---|---|---|---|---|
| 85 dB SPL | quiet background listening | 0.00 mW | 3 mV | 0.4 mA |
| 95 dB SPL | normal listening | 0.01 mW | 11 mV | 1.2 mA |
| 100 dB SPL | loud listening | 0.04 mW | 19 mV | 2.1 mA |
| 105 dB SPL | very loud | 0.13 mW | 34 mV | 3.7 mA |
| 110 dB SPL | peaks on dynamic music | 0.40 mW | 60 mV | 6.7 mA |
Most people listen between 75 and 85 dB. The 100 dB row is the one worth planning around: it gives you headroom for dynamic peaks without designing your system for a volume that would damage your hearing in under fifteen minutes. The safe listening calculator puts numbers on that.
Every source in the database, judged at 100 dB SPL into 9Ω. “Headroom” is how much power is left over above what the headphone needs — 10 dB means ten times the required power, which is what you want for dynamic peaks.
| Source | Type | Price | Power into 9Ω | Headroom | Verdict |
|---|---|---|---|---|---|
| Schiit Ragnarok 2 | desktop amplifier | $1500 | 6.8 W | +52 dB | Comfortable audible hiss |
| Schiit Mjolnir 3 | desktop amplifier | $800 | 2.2 W | +48 dB | Comfortable audible hiss |
| Burson Soloist 3X GT | desktop amplifier | $1500 | 2.2 W | +48 dB | Comfortable audible hiss |
| Chord Hugo TT 2 | desktop amplifier | $5000 | 2.2 W | +48 dB | Comfortable audible hiss |
| Schiit Asgard 3 | desktop amplifier | $250 | 2.0 W | +47 dB | Comfortable audible hiss |
| Ferrum OOR | desktop amplifier | $1800 | 2.0 W | +47 dB | Comfortable audible hiss |
| Topping A90 Discrete | desktop amplifier | $400 | 1.7 W | +46 dB | Comfortable audible hiss |
| Wells Audio Milo | desktop amplifier | $2500 | 1.7 W | +46 dB | Comfortable audible hiss |
| Topping A90 | desktop amplifier | $500 | 1.5 W | +46 dB | Comfortable audible hiss |
| Headamp GS-X Mini | desktop amplifier | $1400 | 1.4 W | +45 dB | Comfortable audible hiss |
| JDS Labs Element III MK2 | desktop DAC/amp | $350 | 1.3 W | +45 dB | Comfortable audible hiss |
| SMSL HO200 | desktop amplifier | $300 | 1.1 W | +45 dB | Comfortable audible hiss |
| iFi iCAN Pro | desktop amplifier | $600 | 1.1 W | +45 dB | Comfortable audible hiss |
| Topping L30 II | desktop amplifier | $130 | 984 mW | +44 dB | Comfortable audible hiss |
| Cayin HA-6A | desktop amplifier | $1800 | 844 mW | +43 dB | Comfortable audible hiss, damping |
| FiiO M17 | portable player | $1800 | 844 mW | +43 dB | Comfortable audible hiss |
| Schiit Magni+ | desktop amplifier | $109 | 562 mW | +41 dB | Comfortable audible hiss |
| Fiio K7 | desktop DAC/amp | $180 | 562 mW | +41 dB | Comfortable audible hiss |
| Fiio K9 Pro | desktop DAC/amp | $380 | 562 mW | +41 dB | Comfortable audible hiss |
| Geshelli Archel Pro | desktop amplifier | $200 | 506 mW | +41 dB | Comfortable audible hiss |
| Schiit Magni Heresy | desktop amplifier | $100 | 450 mW | +41 dB | Comfortable audible hiss |
| SMSL SH-9 | desktop amplifier | $150 | 422 mW | +40 dB | Comfortable audible hiss |
| JDS Labs Atom+ (2nd gen) | desktop amplifier | $100 | 281 mW | +38 dB | Comfortable audible hiss |
| iFi Zen CAN | desktop amplifier | $200 | 281 mW | +38 dB | Comfortable audible hiss |
| HiBy R6 Pro II | portable player | $750 | 211 mW | +37 dB | Comfortable audible hiss |
| FiiO M11S | portable player | $500 | 188 mW | +37 dB | Comfortable audible hiss |
| FiiO KA17 | USB dongle | $150 | 183 mW | +37 dB | Comfortable audible hiss |
| FiiO BTR17 | Bluetooth receiver | $200 | 183 mW | +37 dB | Comfortable audible hiss |
| Astell&Kern SP3000 | portable player | $3700 | 169 mW | +36 dB | Comfortable audible hiss |
| FiiO KA13 | USB dongle | $80 | 155 mW | +36 dB | Comfortable audible hiss |
| Qudelix T71 | Bluetooth receiver | $200 | 112 mW | +34 dB | Comfortable audible hiss |
| Astell&Kern SR35 | portable player | $800 | 112 mW | +34 dB | Comfortable audible hiss |
| FiiO BTR15 | Bluetooth receiver | $110 | 96 mW | +34 dB | Comfortable audible hiss |
| FiiO BTR7 | Bluetooth receiver | $200 | 90 mW | +34 dB | Comfortable audible hiss |
| Questyle M15 | USB dongle | $250 | 84 mW | +33 dB | Comfortable audible hiss |
| Hidizs S9 Pro | USB dongle | $75 | 76 mW | +33 dB | Comfortable audible hiss |
| Sony NW-WM1AM2 | portable player | $1400 | 70 mW | +32 dB | Comfortable audible hiss |
| Qudelix 5K | Bluetooth receiver | $110 | 68 mW | +32 dB | Comfortable audible hiss |
| Moondrop Dawn Pro | USB dongle | $60 | 65 mW | +32 dB | Comfortable audible hiss |
| iBasso DC04 Pro | USB dongle | $90 | 65 mW | +32 dB | Comfortable audible hiss |
| Shanling UP5 | Bluetooth receiver | $130 | 65 mW | +32 dB | Comfortable audible hiss |
| Truthear SHIO | USB dongle | $70 | 60 mW | +32 dB | Comfortable audible hiss |
| Schiit Vali 2+ | desktop amplifier | $200 | 56 mW | +32 dB | Comfortable audible hiss, damping |
| FiiO KA11 | USB dongle | $30 | 56 mW | +32 dB | Comfortable audible hiss |
| ddHiFi TC44 Pro | USB dongle | $110 | 53 mW | +31 dB | Comfortable audible hiss |
| Shanling UA5 | Bluetooth receiver | $220 | 51 mW | +31 dB | Comfortable audible hiss |
| Tempotec Sonata BHD Pro | USB dongle | $40 | 37 mW | +30 dB | Comfortable audible hiss |
| iBasso DC03 Pro | USB dongle | $60 | 34 mW | +29 dB | Comfortable audible hiss |
| Generic CX31993 dongles | USB dongle | $12 | 17 mW | +26 dB | Comfortable audible hiss, damping |
| EarStudio ES100 MK2 | Bluetooth receiver | $90 | 17 mW | +26 dB | Comfortable audible hiss |
| Sony NW-A306 | portable player | $350 | 14 mW | +25 dB | Comfortable audible hiss, damping |
| Apple USB-C dongle (US) | USB dongle | $9 | 8.4 mW | +23 dB | Comfortable audible hiss |
| Apple USB-C dongle (EU) | USB dongle | $9 | 4.2 mW | +20 dB | Comfortable audible hiss |
Hiss. At 134.5 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Vali 2+, would put its hiss at roughly 42 dB SPL in these headphones — clearly audible in quiet passages. The hiss calculator lets you check your own amplifier's noise figure.
Output impedance. At 9Ω these want a source output impedance below 1.12Ω to satisfy the one-eighth rule. 4 of the 53 sources here miss it, the worst being the Schiit Vali 2+ at 6Ω. Above that threshold the source starts shaping the frequency response. Check yours here.
17Ω · 107.0 dB/mW · Easy
See requirements →22Ω · 109.0 dB/mW · Easy
See requirements →27Ω · 107.0 dB/mW · Easy
See requirements →16Ω · 113.0 dB/mW · Easy
See requirements →12Ω · 108.0 dB/mW · Easy
See requirements →12Ω · 108.0 dB/mW · Easy
See requirements →Or open the comparison tool to put any two models side by side, or browse all 316.