/// MEASUREMENT RIG
HEAD HMS II.3 + REW + APx555
Calibrated quarterly. Photos and serial numbers available upon request.
Acoustic head
HEAD acoustics HMS II.3
Calibration: HEAD Berlin lab, quarterly
Standard: IEC 60318-7 ear simulator
Pinna: HATS Type 3.3 high-frequency
FFT analyzer
Room EQ Wizard v5.20
Log sweep: 200ms, 32 averages
Resolution: 1/24 octave smoothing
Output: .frd, .mdat, PNG
Audio analyzer
Audio Precision APx555
THD floor: -110dB
Crosstalk: -130dB
Sample rate: up to 192kHz
Reference amplifier
Stax SRM-T8000
Output voltage: 6.2 Vrms
Output impedance: 0.5 ohm
Use case: headphone reference drive
Source DAC
RME ADI-2 Pro FS R BE
SNR: 124 dBA
THD+N: -116 dB
Reference for chain transparency
Environment
Treated 14 sqm room
RT60: 0.22s
Ambient noise: less than 22 dBA
Power: isolation transformer + ground star