The Audeze LCD-2 Closed-Back is 70Ω at 101.0 dB/mW; the Audeze LCD-4 is 200Ω at 97.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The LCD-4 needs 4.0 dB more than the LCD-2 Closed-Back to reach the same loudness — 2.0 mW against 0.79 mW.
| Specification | LCD-2 Closed-Back | LCD-4 |
|---|---|---|
| Impedance | 70 Ω | 200 Ω |
| Sensitivity | 101.0 dB/mW | 97.0 dB/mW |
| Sensitivity (voltage) | 112.5 dB/V | 104.0 dB/V |
| Power for 100 dB | 0.79 mW | 2.0 mW |
| Voltage for 100 dB | 0.24 V | 0.63 V |
| Current for 100 dB | 3.4 mA | 3.2 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 8.75 Ω | 25.00 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
Every source in the database that drives one of them drives the other. On power, the choice between these two changes nothing about what amplifier you need.
18 sources are low enough in output impedance for the LCD-4 under the one-eighth rule but not for the LCD-2 Closed-Back (Zoom AMS-22, Arturia MiniFuse 2, Arturia MiniFuse 1, 15 more).
1 source stays below the audible-hiss threshold with the LCD-4 but crosses it with the LCD-2 Closed-Back (Schiit Mjolnir 3).
280 of the 280 sources here reach 100 dB on both.
The LCD-4 is more demanding than 92% of the 567 non-electrostatic models in this database; the LCD-2 Closed-Back than 64%.
| dB SPL | LCD-2 Closed-Back power | LCD-2 Closed-Back voltage | LCD-4 power | LCD-4 voltage |
|---|---|---|---|---|
| 80 | 7.9 µW | 24 mV | 0.02 mW | 63 mV |
| 85 | 0.03 mW | 42 mV | 0.06 mW | 0.11 V |
| 90 | 0.08 mW | 75 mV | 0.20 mW | 0.20 V |
| 95 | 0.25 mW | 0.13 V | 0.63 mW | 0.36 V |
| 100 | 0.79 mW | 0.24 V | 2.0 mW | 0.63 V |
| 105 | 2.5 mW | 0.42 V | 6.3 mW | 1.12 V |
| Source | Price | Headroom, LCD-2 Closed-Back | Headroom, LCD-4 | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 12.4 dB | 3.8 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 20.6 dB | 12.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 12.3 dB | 3.6 dB | 0.5 Ω | 8.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 69 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 cheapest of the 69 is the JadeAudio JA11, at $20. It leaves 12.4 dB of headroom on the LCD-2 Closed-Back and 3.8 dB on the LCD-4, its output impedance is 0.5 Ω against a one-eighth limit of 8.75 Ω and 25.00 Ω, and its noise figure puts the hiss floor 23 dB and 31 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| LCD-2 Closed-Back | 10Hz - 50kHz | not printed | not printed |
| LCD-4 | 5Hz - 50kHz | not printed | not printed |
Audeze prints 10Hz - 50kHz for the LCD-2 Closed-Back and 5Hz - 50kHz for the LCD-4.
Neither range has a tolerance printed beside it, so a wider range on one sheet is not deeper bass or more treble.
Not a measurement; maker by maker.
Both have a page of their own. In full: Audeze LCD-2 Closed-Back and Audeze LCD-4. Every figure on this page comes from what Audeze published, or is derived from it — what that maker publishes, counted.