natus Madsen A450, Руководство пользователя

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Type AE calibration:
• The output sound pressure level and frequency response are specified in terms of free-field equivalent sound pressure
level.
• The loudspeaker output is specified as measured under free-field conditions, at 1 m distance, and on the axis of the
loudspeaker.
• Bone vibrator output is not corrected to obtain a free-field equivalent sound force level; uncorrected output is pro-
duced (please see below under “Type A”).
• Calibration of speech signals is performed using either a 1 kHz pure tone (earphones) or 1 kHz warble tone (loud-
speakers).
Type A calibration:
• The output sound pressure level and frequency response are specified in terms of coupler level. See table below for
coupler/ear simulator used.
• The loudspeaker output is specified as measured under free-field conditions, at 1 m distance, and on the axis of the
loudspeaker.
• Bone conductor output is not corrected to obtain a free-field equivalent sound force level; uncorrected output meas-
ured by an artificial mastoid (IEC 60318-6) is produced.
• Calibration of speech signals is performed using either a 1 kHz pure tone (earphones) or 1 kHz warble tone (loud-
speakers).
Transducer type Coupler/ear simulator
Supra-aural earphone IEC 60318-3
Insert phone IEC 60318-5
Attenuator
1 or 5 dB step resolution over the entire range.
HL Range
The maximum output levels from Madsen A450 depend on the actual sensitivity of the individual transducers, and they
will be slightly different for each device. However, the minimum requirements from IEC and ANSI standards are fulfilled for
all devices per the IEC and ANSI standards listed in this Technical Specifications section.
They are specified in the following.
Frequencies and minimum output levels (dB HL)
Frequency (Hz) Supra-aural Circum-aural Insert phone Bone conductor
125 60 60 60 N/A
250 80 80 80 45
500 110 110 110 60
1000 110 110 110 70
Madsen A450 25
16 Technical specifications