What we know about the measurement:

Polk Audio Monitor 40 Series II is a passive bookshelves that cost around 200 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: 88.5dB (avg. 100Hz-1kHz for 2.83V measured at 1m).
  • -3dB (resp. -6db) point v.s. reference is at 82.0Hz (resp. 67.4Hz).
  • Reference level is normalised to 0.2dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 2.7dB over the same frequency range.
  • Directivity
    • Horizontal directivity is (-50.0°, 50.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
    • Vertical directivity is (-20.0°, 20.0°) between 1kHz and 10kHz. Angle computed for +/-6dB.
  • Tonality (Preference) Score
    • Tonality (Preference) Score is 2.19 and would be 4.94 with a perfect subwoofer.
      • Details: NBD: ON 0.56, LW 0.549, SP 0.465, PIR 0.497; SM: SP0.38, PIR0.061; LFQ 0.685, LFX 62Hz
    • Tonality (Preference) Score is 5.6 with an EQ and would be 7.97 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.37, LW 0.343, SP 0.387, PIR 0.299; SM: SP0.916, PIR0.907; LFQ 0.685, LFX 51Hz
  • Link to Original review.
Polk Audio Monitor 40 Series II
AutomaticEQ (IIR)
Set preamp gain to: -3.0dB.
Type Freq Q Gain
5 82.0 1.06 2.96
3 462.0 1.97 2.12
3 903.0 1.91 -1.15
3 1067.0 2.9 1.88
3 1648.0 2.85 2.84
3 4803.0 1.75 -1.7
3 5870.0 1.58 -2.58
3 11843.0 1.89 -2.68
3 13997.0 1.06 -2.61
Download

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

Polk Audio Monitor 40 Series II filters_auto_eq

AutomaticEQ

Polk Audio Monitor 40 Series II filters_eq_full

Target v.s. EQ

Polk Audio Monitor 40 Series II
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 0.25
3 630.0 2.14 0.0
3 1000.0 2.14 0.0
3 1600.0 2.14 0.5
3 2500.0 2.14 -0.5
3 4000.0 2.14 -0.25
3 6300.0 2.14 -0.75
3 10000.0 2.14 -0.5
3 16000.0 2.14 0.0
Download

These EQ is designed for a 15 bands graphical EQ.

Polk Audio Monitor 40 Series II
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 -0.25
3 160.0 4.32 -0.25
3 200.0 4.32 0.0
3 250.0 4.32 -0.25
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 -0.25
3 1000.0 4.32 0.0
3 1250.0 4.32 -0.25
3 1600.0 4.32 0.25
3 2000.0 4.32 0.0
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 -0.5
3 6300.0 4.32 -0.5
3 8000.0 4.32 -0.25
3 10000.0 4.32 -0.25
3 12000.0 4.32 -0.75
3 16000.0 4.32 0.25
3 20000.0 4.32 0.0
Download

These EQ is designed for a 31 bands graphical EQ.

Polk Audio Monitor 40 Series II: comparison between EQs
Polk Audio Monitor 40 Series II

Comparison betweens various EQs

Polk Audio Monitor 40 Series II

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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