What we know about the measurement:

Hedd Type 05 A-CORE is an active bookshelves that cost around 700 USD each.

  • Quality of the measurement data is high.
  • Origin of the data is ASR.
  • Format of the data is generated by a Klippel NFS .
  • -3dB (resp. -6db) point v.s. reference is at 43.9Hz (resp. 39.6Hz).
  • Reference level is normalised to 0.1dB computed over the frequency range [300.0Hz, 5000.0Hz].
  • Frequency deviation is 2.7dB over the same frequency range.
  • Tonality (Preference) Score
    • Tonality (Preference) Score is 5.31 and would be 7.19 with a perfect subwoofer.
      • Details: NBD: ON 0.456, LW 0.404, SP 0.404, PIR 0.373; SM: SP0.909, PIR0.76; LFQ 0.747, LFX 39Hz
    • Tonality (Preference) Score is 6.34 with an EQ and would be 8.22 with a perfect subwoofer and the same EQ.
      • Details: NBD: ON 0.356, LW 0.289, SP 0.298, PIR 0.248; SM: SP0.964, PIR0.936; LFQ 0.747, LFX 39Hz
  • Link to Original review.
  • Vendor specifications:
    • SPL
      • peak: 106 dB
    • Size
      • Width 180mm
      • Height 308mm
      • Depth 235mm
    • Weight 6.2kg
Hedd Type 05 A-CORE
AutomaticEQ (IIR)
Set preamp gain to: -1.7dB.
Type Freq Q Gain
PK 1954.0 1.49 2.96
PK 72.0 2.14 -2.14
PK 1010.0 2.99 -1.17
PK 579.0 2.99 2.54
PK 1532.0 0.25 -2.64
PK 270.0 0.73 1.83
PK 879.0 2.97 2.81
Download
This EQ optimise the Harman score and is a good start for far field listening like in your living room.
Improvement made by adding the above EQ
EQ
AutoEQ
Target v.s. EQ
Target v.s. EQ
Histogram of errors
On Axis (fullrange)
Listening Window (fullrange)
Predicted In-Room Response (fullrange)
;