What we know about the measurement:

PSI Audio A21-M is an active bookshelves that cost around 3100 USD each.

  • Quality of the measurement data is low.
  • Origin of the data is Sound and Recording.
  • Format of the data is a scanned image .
  • -3dB (resp. -6db) point v.s. reference is at 36.5Hz (resp. 33.6Hz).
  • Reference level is normalised to 0.6dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 1.7dB over the same frequency range.
  • Tonality (Preference) Score
    • Tonality (Preference) Score is 6.18 and would be 7.8 with a perfect subwoofer.
      • Details: NBD: ON 0.299, LW 0.356, SP 0.451, PIR 0.368; SM: SP0.912, PIR0.851; LFQ 1.943, LFX 34Hz
    • Tonality (Preference) Score is 6.99 with an EQ and would be 8.59 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.182, LW 0.218, SP 0.356, PIR 0.244; SM: SP0.954, PIR0.902; LFQ 1.943, LFX 34Hz
  • Link to Original review.
  • Vendor specifications:
    • Dispersion: 80° horizontal and 30° vertical.
    • SPL
      • max: 106 dB
      • peak: 121 dB
    • Size
      • Width 250mm
      • Height 400mm
      • Depth 300 mm)
    • Weight 12.8 kg
PSI Audio A21-M
AutomaticEQ (IIR)
Set preamp gain to: -2.4dB.
Type Freq Q Gain
5 36.0 0.59 2.97
3 66.0 0.73 -2.76
3 102.0 0.89 2.8
3 354.0 2.95 1.09
3 447.0 0.59 -1.89
3 739.0 2.99 2.73
3 1704.0 1.17 1.0
3 3110.0 2.79 -1.47
3 9691.0 1.2 1.4
Download

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

PSI Audio A21-M filters_auto_eq

AutomaticEQ

PSI Audio A21-M filters_eq_full

Target v.s. EQ

PSI Audio A21-M
Graphic EQ 15 bands
Set preamp gain to: -0.5dB.
Type Freq Q Gain
3 25.0 2.14 0.25
3 40.0 2.14 0.0
3 63.0 2.14 0.0
3 100.0 2.14 0.0
3 160.0 2.14 0.0
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 0.0
3 1600.0 2.14 0.0
3 2500.0 2.14 0.0
3 4000.0 2.14 0.25
3 6300.0 2.14 0.0
3 10000.0 2.14 0.25
3 16000.0 2.14 0.5
Download

These EQ is designed for a 15 bands graphical EQ.

PSI Audio A21-M
Graphic EQ 31 bands
Set preamp gain to: -0.6dB.
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 0.25
3 50.0 4.32 -0.25
3 63.0 4.32 -0.25
3 80.0 4.32 0.0
3 100.0 4.32 0.0
3 125.0 4.32 0.0
3 160.0 4.32 0.0
3 200.0 4.32 0.0
3 250.0 4.32 -0.25
3 315.0 4.32 -0.25
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 0.0
3 1600.0 4.32 0.0
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 0.0
3 5000.0 4.32 0.0
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 0.0
3 16000.0 4.32 0.5
3 20000.0 4.32 0.0
Download

These EQ is designed for a 31 bands graphical EQ.

PSI Audio A21-M: comparison between EQs
PSI Audio A21-M

Comparison betweens various EQs

PSI Audio A21-M

Improvements made by EQ

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