16 Technical Specifications
16.1 MADSEN Astera²
Type identification
MADSEN Astera² is type 1066 from GNOtometricsA/S.
Channels
Two separate and identical channels
Frequency range
TDH39 earphones: Standard frequencies: 125 - 12500Hz
HDA 300 earphones: Standard frequencies: 125 - 20000Hz
Insert earphones: Standard frequencies: 125 - 8000Hz
BC: Standard frequencies: 250 - 8000Hz
SF: Standard frequencies: 125 - 20000Hz
Tone accuracy: >0.03%
FRESH noise stimulus: Available in entire frequency range within the transducer specified range.(for SF 125
- 12500 Hz). Accuracy 0.3%
Narrow Band Noise masking: Available in entire frequency range
Frequency resolution: 1/48, 1/24, 1/12, and 1/6 oct, 1Hz step
Stimulustypes
• Tone
• Warble
• Pulsed tone
• Pulsed warble
• FRESH noise Frequency-specific hearing assessment noise.
Consists of noise bands, with frequency-specific filter width.
The FRESH noise is filtered to obtain very steep slopes outside the passband.
• Pulsed FRESH noise
Masking types
• Narrow Band Noise
– AC and BC
– SF
Correlated
Non-correlated
A
Otometrics - MADSEN Astera²
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16 Technical Specifications