What we know about the measurement:

KEF LS50 is a passive bookshelves that cost around 1500 USD for a pair.

  • Quality of the measurement data is high.
  • Origin of the data is ASR.
  • Format of the data is generated by a Klippel NFS .
  • Sensitivity: 83.9dB (avg. 100Hz-1kHz for 2.83V estimated at 1m)
  • -3dB (resp. -6db) point v.s. reference is at 82.8Hz (resp. 49.1Hz).
  • Reference level is normalised to 0.6dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 3.9dB over the same frequency range.
  • Directivity
    • Horizontal directivity is (-50.0°, 50.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
    • Vertical directivity is (-50.0°, 50.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
  • Tonality (Preference) Score
    • Tonality (Preference) Score is 4.47 and would be 6.69 with a perfect subwoofer.
      • Details: NBD: ON 0.6, LW 0.526, SP 0.428, PIR 0.437; SM: SP0.953, PIR0.783; LFQ 0.546, LFX 47Hz
    • Tonality (Preference) Score is 6.11 with an EQ and would be 8.18 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.372, LW 0.312, SP 0.307, PIR 0.259; SM: SP0.967, PIR0.95; LFQ 0.546, LFX 43Hz
  • Vertical measurement
  • Link to Original review.
KEF LS50
AutomaticEQ (IIR)
Set preamp gain to: -2.3dB.
Type Freq Q Gain
5 102.0 0.48 2.96
3 404.0 1.17 0.88
3 584.0 2.47 2.23
3 817.0 2.02 -1.24
3 1541.0 2.55 2.96
3 2813.0 1.97 -0.55
3 4803.0 2.78 -2.85
3 7669.0 0.72 1.54
5 14965.0 0.76 -0.64
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These EQ optimise the Harman score and is a good start for far field listening like in your living room.

KEF LS50 filters_auto_eq

AutomaticEQ

KEF LS50 filters_eq_full

Target v.s. EQ

KEF LS50
flipflop@ASR (IIR)
Set preamp gain to: -1.2dB.
Type Freq Q Gain
3 466.0 4.209 -0.6
3 527.0 1.889 2.2
3 857.0 1.0 -2.7
3 1224.0 5.0 -2.0
3 1459.0 1.123 4.6
3 1639.0 4.703 -11.5
3 1645.0 4.807 11.7
3 2285.0 1.0 -3.1
3 2400.0 18.0 -0.6
3 4429.0 1.0 -1.4
3 4873.0 5.0 -2.3
3 6985.0 4.998 -2.1
3 8917.0 5.0 -3.4
3 10636.0 5.0 -3.1
3 11460.0 5.0 -2.2
3 12192.0 1.001 12.0
3 13179.0 1.386 -12.3
3 14084.0 5.0 1.2
3 16192.0 5.0 -1.5
3 17760.0 5.0 -1.6
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These EQ is designed by ASR member flipflop.

KEF LS50
Graphic EQ 15 bands
Set preamp gain to: -0.7dB.
Type Freq Q Gain
3 25.0 2.14 0.5
3 40.0 2.14 0.5
3 63.0 2.14 0.5
3 100.0 2.14 0.25
3 160.0 2.14 -0.25
3 250.0 2.14 -0.25
3 400.0 2.14 0.0
3 630.0 2.14 0.0
3 1000.0 2.14 -0.25
3 1600.0 2.14 0.25
3 2500.0 2.14 -0.5
3 4000.0 2.14 -0.5
3 6300.0 2.14 -0.25
3 10000.0 2.14 0.0
3 16000.0 2.14 0.0
Download

These EQ is designed for a 15 bands graphical EQ.

KEF LS50
Graphic EQ 31 bands
Set preamp gain to: -0.8dB.
Type Freq Q Gain
3 20.0 4.32 0.0
3 25.0 4.32 0.5
3 31.0 4.32 0.5
3 40.0 4.32 0.5
3 50.0 4.32 0.5
3 63.0 4.32 0.5
3 80.0 4.32 0.5
3 100.0 4.32 0.25
3 125.0 4.32 0.0
3 160.0 4.32 -0.25
3 200.0 4.32 -0.25
3 250.0 4.32 0.0
3 315.0 4.32 0.0
3 400.0 4.32 0.0
3 500.0 4.32 0.25
3 630.0 4.32 0.0
3 800.0 4.32 -0.25
3 1000.0 4.32 0.0
3 1250.0 4.32 0.0
3 1600.0 4.32 0.5
3 2000.0 4.32 0.0
3 2500.0 4.32 -0.25
3 3150.0 4.32 -0.5
3 4000.0 4.32 -0.5
3 5000.0 4.32 -0.5
3 6300.0 4.32 0.0
3 8000.0 4.32 0.25
3 10000.0 4.32 0.25
3 12000.0 4.32 0.25
3 16000.0 4.32 0.0
3 20000.0 4.32 0.0
Download

These EQ is designed for a 31 bands graphical EQ.

KEF LS50: comparison between EQs
KEF LS50

Comparison betweens various EQs

KEF LS50

Improvements made by EQ

Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
Frequency Frequency with EQ
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