The Focal Lensys Professional is 26Ω at 100.0 dB/mW; the Focal Listen Professional is 32Ω at 107.1 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The Lensys Professional needs 7.1 dB more than the Listen Professional to reach the same loudness — 1.0 mW against 0.19 mW.
| Specification | Lensys Professional | Listen Professional |
|---|---|---|
| Impedance | 26 Ω | 32 Ω |
| Sensitivity | 100.0 dB/mW | 107.1 dB/mW |
| Sensitivity (voltage) | 115.9 dB/V | 122.0 dB/V |
| Power for 100 dB | 1.0 mW | 0.19 mW |
| Voltage for 100 dB | 0.16 V | 79 mV |
| Current for 100 dB | 6.2 mA | 2.5 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 3.25 Ω | 4.00 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.
2 sources stay below the audible-hiss threshold with the Lensys Professional but cross it with the Listen Professional (FiiO BTR11, Rupert Neve RNHP).
280 of the 280 sources here reach 100 dB on both.
The Lensys Professional is more demanding than 51% of the 567 non-electrostatic models in this database; the Listen Professional than 25%.
| dB SPL | Lensys Professional power | Lensys Professional voltage | Listen Professional power | Listen Professional voltage |
|---|---|---|---|---|
| 80 | 0.01 mW | 16 mV | 1.9 µW | 8 mV |
| 85 | 0.03 mW | 29 mV | 6.2 µW | 14 mV |
| 90 | 0.10 mW | 51 mV | 0.02 mW | 25 mV |
| 95 | 0.32 mW | 91 mV | 0.06 mW | 44 mV |
| 100 | 1.0 mW | 0.16 V | 0.19 mW | 79 mV |
| 105 | 3.2 mW | 0.29 V | 0.62 mW | 0.14 V |
| Source | Price | Headroom, Lensys Professional | Headroom, Listen Professional | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 13.9 dB | 21.9 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 23.2 dB | 30.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 20.1 dB | 27.1 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 67 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 67 is the JadeAudio JA11, at $20. It leaves 13.9 dB of headroom on the Lensys Professional and 21.9 dB on the Listen Professional, its output impedance is 0.5 Ω against a one-eighth limit of 3.25 Ω and 4.00 Ω, and its noise figure puts the hiss floor 20 dB and 13 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Lensys Professional | 5Hz - 22kHz | ±3 dB | not printed |
| Listen Professional | 5 Hz – 23 kHz | ±3 dB | not printed |
Focal prints 5Hz - 22kHz for the Lensys Professional and 5 Hz – 23 kHz for the Listen Professional.
For both: Focal puts the tolerance in the row heading rather than beside the numbers: the label itself reads "Frequency response (+/- 3dB)".
Both sheets print a tolerance, which is rare enough to be worth pointing at: only 58 of the 490 models with a printed range do. These two ranges can be set against each other, because each of them says how far down the response is allowed to be at the ends.
Not a measurement; maker by maker.
Both have a page of their own. In full: Focal Lensys Professional and Focal Listen Professional. Every figure on this page comes from what Focal published, or is derived from it — what that maker publishes, counted.