What we know about the measurement:

JBL Stage A125C is a passive center that cost around 120 USD

  • Quality of the measurement data is high.
  • Origin of the data is ASR.
  • Format of the data is generated by a Klippel NFS .
  • Sensitivity: 87.3dB (avg. 100Hz-1kHz for 2.83V measured at 1m).
  • -3dB (resp. -6db) point v.s. reference is at 98.1Hz (resp. 77.6Hz).
  • 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 (-60.0°, 60.0°) 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 2.37 and would be 5.51 with a perfect subwoofer.
      • Details: NBD: ON 0.564, LW 0.47, SP 0.508, PIR 0.445; SM: SP0.519, PIR0.244; LFQ 1.238, LFX 77Hz
    • Tonality (Preference) Score is 5.47 with an EQ and would be 7.89 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.416, LW 0.302, SP 0.343, PIR 0.262; SM: SP0.894, PIR0.876; LFQ 1.061, LFX 52Hz
  • Vertical measurement
  • Link to Original review.
JBL Stage A125C
AutomaticEQ (IIR)
Set preamp gain to: -5.0dB.
Type Freq Q Gain
LS 98.0 1.06 2.98
PK 98.0 0.3 2.99
PK 143.0 1.51 -2.53
PK 194.0 1.08 -2.58
PK 565.0 2.73 1.59
PK 764.0 2.97 1.98
PK 4966.0 1.46 -2.76
PK 9691.0 2.61 -1.92
PK 16000.0 1.18 -2.83
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These EQ optimise the Harman score and is a good start for far field listening like in your living room.

JBL Stage A125C filters_auto_eq

AutomaticEQ

JBL Stage A125C filters_eq_full

Target v.s. EQ

JBL Stage A125C
Graphic EQ 15 bands
Set preamp gain to: -1.2dB.
Type Freq Q Gain
PK 25.0 2.14 0.75
PK 40.0 2.14 0.75
PK 63.0 2.14 0.75
PK 100.0 2.14 0.5
PK 160.0 2.14 -0.25
PK 250.0 2.14 0.0
PK 400.0 2.14 0.5
PK 630.0 2.14 1.0
PK 1000.0 2.14 0.5
PK 1600.0 2.14 0.5
PK 2500.0 2.14 0.25
PK 4000.0 2.14 -0.25
PK 6300.0 2.14 0.0
PK 10000.0 2.14 0.0
PK 16000.0 2.14 0.0
Download

These EQ is designed for a 15 bands graphical EQ.

JBL Stage A125C
Graphic EQ 31 bands
Set preamp gain to: -0.8dB.
Type Freq Q Gain
PK 20.0 4.32 0.0
PK 25.0 4.32 0.5
PK 31.0 4.32 0.5
PK 40.0 4.32 0.5
PK 50.0 4.32 0.5
PK 63.0 4.32 0.5
PK 80.0 4.32 0.5
PK 100.0 4.32 0.5
PK 125.0 4.32 0.0
PK 160.0 4.32 -0.25
PK 200.0 4.32 -0.25
PK 250.0 4.32 0.0
PK 315.0 4.32 0.0
PK 400.0 4.32 0.0
PK 500.0 4.32 0.25
PK 630.0 4.32 0.25
PK 800.0 4.32 0.25
PK 1000.0 4.32 -0.25
PK 1250.0 4.32 -0.25
PK 1600.0 4.32 0.0
PK 2000.0 4.32 -0.25
PK 2500.0 4.32 -0.25
PK 3150.0 4.32 -0.25
PK 4000.0 4.32 -0.5
PK 5000.0 4.32 -0.5
PK 6300.0 4.32 -0.25
PK 8000.0 4.32 0.0
PK 10000.0 4.32 -0.5
PK 12000.0 4.32 0.0
PK 16000.0 4.32 -0.75
PK 20000.0 4.32 0.0
Download

These EQ is designed for a 31 bands graphical EQ.

JBL Stage A125C: comparison between EQs
JBL Stage A125C

Comparison betweens various EQs

JBL Stage A125C

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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