What we know about the measurement:

KEF R8a is a passive surround that cost around 1400 USD for a pair.

  • Quality of the measurement data is high.
  • Origin of the data is ErinsAudioCorner.
  • Format of the data is generated by a Klippel NFS .
  • Sensitivity: 84.3dB (avg. 100Hz-1kHz for 2.83V estimated at 1m)
  • -3dB (resp. -6db) point v.s. reference is at 134.0Hz (resp. 109.1Hz).
  • Reference level is normalised to 0.3dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 2.6dB over the same frequency range.
  • Directivity
    • Horizontal directivity is (-40.0°, 50.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
    • Vertical directivity is (-40.0°, 40.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
  • Tonality (Preference) Score
    • Note: The tonality (Preference) score does not make sense for surround speakers. Don't give too much credits to the value.
    • Tonality (Preference) Score is 1.55 and would be 5.39 with a perfect subwoofer.
      • Details: NBD: ON 0.486, LW 0.429, SP 0.442, PIR 0.425; SM: SP0.67, PIR0.085; LFQ 0.946, LFX 112Hz
    • Tonality (Preference) Score is 5.13 with an EQ and would be 8.39 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.291, LW 0.228, SP 0.287, PIR 0.238; SM: SP0.961, PIR0.927; LFQ 0.8, LFX 82Hz
  • Link to original Review: eac review. Links to other reviews: white_paper review .
KEF R8a
AutomaticEQ (IIR)
Set preamp gain to: -4.7dB.
Type Freq Q Gain
3 98.0 2.24 3.0
3 190.0 1.11 -2.51
3 197.0 0.25 2.99
3 1046.0 3.0 2.91
3 1083.0 0.25 -2.03
3 8397.0 1.12 -4.23
3 16239.0 0.27 0.99
Download

These EQ optimise the Harman score and is a good start for far field listening like in your living room.

KEF R8a filters_auto_eq

AutomaticEQ

KEF R8a filters_eq_full

Target v.s. EQ

KEF R8a
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 0.5
3 160.0 2.14 0.25
3 250.0 2.14 0.0
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 -0.75
3 10000.0 2.14 -0.75
3 16000.0 2.14 -0.25
Download

These EQ is designed for a 15 bands graphical EQ.

KEF R8a
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 0.5
3 125.0 4.32 0.5
3 160.0 4.32 0.25
3 200.0 4.32 0.0
3 250.0 4.32 0.0
3 315.0 4.32 0.0
3 400.0 4.32 0.25
3 500.0 4.32 0.25
3 630.0 4.32 0.0
3 800.0 4.32 0.0
3 1000.0 4.32 0.25
3 1250.0 4.32 0.25
3 1600.0 4.32 0.0
3 2000.0 4.32 -0.25
3 2500.0 4.32 -0.25
3 3150.0 4.32 -0.25
3 4000.0 4.32 -0.25
3 5000.0 4.32 -0.25
3 6300.0 4.32 -0.5
3 8000.0 4.32 -0.5
3 10000.0 4.32 -0.5
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 R8a: comparison between EQs
KEF R8a

Comparison betweens various EQs

KEF R8a

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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