The Audeze LCD-2 Closed-Back is 70Ω with a sensitivity of 101.0 dB/mW, which is 112.5 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 0.79 mW, or 0.24 V 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 280 sources in the database, 279 have at least 10 dB of headroom and another 1 have enough. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.
From my own rack. I have owned every version of the LCD-2, but at different times, so I never compared them side by side.
Sensitivity here is in dB per milliwatt. Why the unit matters.
Audeze publishes this directly as 101 dB/1mW (1 mW, at Drum Reference Point), per milliwatt, so nothing was converted.
The maker adds a power recommendation of its own: Max power handling 5W RMS; minimum power requirement >100mW; recommended power level >250mW
Source: audeze.com. How this data was built.
| As it is labelled | As printed | Tolerance | Standard |
|---|---|---|---|
| Frequency response | 10Hz - 50kHz | not printed | not printed |
Audeze prints 10Hz - 50kHz for the Audeze LCD-2 Closed-Back, under the heading “Frequency response”. Source: audeze.com.
No tolerance is printed with it, so “10Hz - 50kHz” says nothing about how loud this headphone actually is at 10 Hz.
Only what the maker printed; maker by maker.
| Level | What it is | Power | Voltage | Current |
|---|---|---|---|---|
| 85 dB SPL | quiet background listening | 0.03 mW | 42 mV | 0.6 mA |
| 95 dB SPL | normal listening | 0.25 mW | 0.13 V | 1.9 mA |
| 100 dB SPL | loud listening | 0.79 mW | 0.24 V | 3.4 mA |
| 105 dB SPL | very loud | 2.5 mW | 0.42 V | 6.0 mA |
| 110 dB SPL | peaks on dynamic music | 7.9 mW | 0.75 V | 10.7 mA |
Most people listen between 75 and 85 dB; the 100 dB row leaves room for peaks.
The 15 cheapest of the 280 sources here that reach 100 dB SPL into 70Ω with at least 10 dB of headroom and no known hiss or output-impedance problem with these headphones. All 280 sources, judged for these headphones.
| Source | Type | Price | Power into 70Ω | Headroom | Verdict |
|---|---|---|---|---|---|
| JadeAudio JA11 | USB dongle | $20 | 14 mW | +12 dB | Comfortable |
| FiiO SnowSky Tiny A | USB dongle | $22 | 16 mW | +13 dB | Comfortable |
| FiiO SnowSky Tiny B | USB dongle | $22 | 16 mW | +13 dB | Comfortable |
| FiiO KA11 | USB dongle | $29 | 92 mW | +21 dB | Comfortable |
| Tanchjim Stargate II | USB dongle | $40 | 34 mW | +16 dB | Comfortable |
| ddHiFi TC35AL | USB dongle | $46 | 96 mW | +21 dB | Comfortable |
| ddHiFi TC35Air | USB dongle | $46 | 96 mW | +21 dB | Comfortable |
| Fosi Audio N3 | Bluetooth receiver | $50 | 63 mW | +19 dB | Comfortable |
| Hidizs SD2 | USB dongle | $50 | 32 mW | +16 dB | Comfortable |
| FiiO BTR13 | Bluetooth receiver | $59 | 45 mW | +18 dB | Comfortable |
| iFi GO link | USB dongle | $59 | 35 mW | +16 dB | Comfortable |
| Kiwi Ears Allegro Pro | USB dongle | $60 | 31 mW | +16 dB | Comfortable |
| ddHiFi TC35Pro (Mountain2) | USB dongle | $66 | 30 mW | +16 dB | Comfortable |
| iBasso DC03 Pro | USB dongle | $69 | 45 mW | +18 dB | Comfortable |
| DUNU DTC 480 | USB dongle | $70 | 30 mW | +16 dB | Comfortable |
Hiss. At 112.5 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Mjolnir 3, would put its hiss at roughly 21 dB SPL in these headphones — clearly audible in quiet passages. Check your own source.
Output impedance. At 70Ω these want a source output impedance below 8.75Ω to satisfy the one-eighth rule; 34 of the 192 sources that publish one miss it. Check yours here.
70Ω · 101.0 dB/mW · Easy
See requirements →70Ω · 101.0 dB/mW · Easy
See requirements →35Ω · 90.0 dB/mW · Moderate
See requirements →35Ω · 98.0 dB/mW · Easy
See requirements →14Ω · 94.0 dB · Easy
See requirements →28Ω · 97.0 dB/mW · Easy
See requirements →