What we know about the measurement:

Optimal Audio Cuboid 8 is a passive bookshelves that cost around 490 USD each.

  • Quality of the measurement data is low.
  • Origin of the data is Optimal Audio.
  • Format of the data is a GLL file .
  • -3dB (resp. -6db) point v.s. reference is at 51.5Hz (resp. 45.0Hz).
  • Reference level is normalised to -0.2dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 3.5dB over the same frequency range.
  • Tonality (Preference) Score
    • Tonality (Preference) Score is 2.92 and would be 5.09 with a perfect subwoofer.
      • Details: NBD: ON 0.635, LW 0.688, SP 0.856, PIR 0.748; SM: SP0.653, PIR0.532; LFQ 0.413, LFX 46Hz
    • Tonality (Preference) Score is 5.71 with an EQ and would be 7.49 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.408, LW 0.418, SP 0.539, PIR 0.444; SM: SP0.938, PIR0.93; LFQ 0.413, LFX 37Hz
  • Vendor specifications:
    • Dispersion: 90° horizontal and 50° vertical.
    • Sensitivity 92 dB
    • Impedance 8 Ohm
    • Size
      • Width 256mm
      • Height 422mm
      • Depth 261mm
    • Weight 10.0kg
Optimal Audio Cuboid 8
AutomaticEQ (IIR)
Set preamp gain to: -2.7dB.
Type Freq Q Gain
PK 36.0 0.76 2.99
PK 130.0 1.2 -5.62
PK 879.0 2.99 -2.61
PK 3068.0 0.92 2.99
PK 4051.0 3.0 -2.82
PK 7308.0 0.98 -5.75
PK 13186.0 2.07 -7.04
Download

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

Optimal Audio Cuboid 8 filters_auto_eq

AutomaticEQ

Optimal Audio Cuboid 8 filters_eq_full

Target v.s. EQ

Optimal Audio Cuboid 8
AutomaticEQ LW (IIR)
Set preamp gain to: -2.2dB.
Type Freq Q Gain
PK 52.0 2.99 2.99
PK 67.0 3.0 -0.47
PK 134.0 1.3 -5.39
PK 879.0 2.99 -3.58
PK 3177.0 0.29 1.93
PK 6144.0 1.23 -3.48
PK 13186.0 2.39 -3.76
Download

These EQ optimise for a flat listening window and is a good start for near field listening like on your desk.

Optimal Audio Cuboid 8: comparison between EQs
Optimal Audio Cuboid 8

Comparison betweens various EQs

Optimal Audio Cuboid 8

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
Frequency Frequency with EQ
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