Interacoustics AT235 - Page 56

AT235 Instructions for Use - EN Page 50
Calibration Properties
Calibrated Transducers:
Contralateral Earphone:
Telephonics TDH39/DD45 with a static force of 4.5N
0.5N and/or EARtone 3A and/or CIR33 insert phone
Probe system:
Ipsilateral Earphone: is integrated in the probe system
Probe frequency transmitter and receiver and
pressure transducer is integrated in the probe system
Accuracy:
General
Generally the instrument is made and calibrated to be
within and better than the tolerances required in the
specified standards:
Reflex Frequencies:
1%
Contralateral Reflex and
Audiometer Tone Levels:
3 dB for 250 to 4000Hz and 5 dB for 6000 to 8000Hz
Ipsilateral Reflex Tone
Levels:
5 dB for 500 to 2000Hz and +5/-10 dB for 3000 to
4000Hz
Pressure measurement :
Compliance measurement:
5% or 10 daPa, whichever is greater
5% or 0.1 ml, whichever is greater
Stimulus Presentation
Control:
Reflexes:
ON-OFF ratio = ≥ 70 dB
Rise time = 20 ms
Fall time = 20 ms
A weighted SPL in Off = 31 dB
Impedance Calibration Properties
Probe tone
Frequencies:
226 Hz 1%, 678 Hz 1%, 800 Hz 1%, 1000 Hz 1%
Level:
85 dB SPL 1.5 dB measured in an IEC 60318-5
acoustic coupler. The level is constant for all volumes
in the measurement range.
Distortion:
Max 1% THD
Compliance
Range:
0.1 to 8.0 ml
Temperature
dependence:
-0.003 ml/C
Pressure dependence:
-0.00020 ml/daPa
Reflex sensitivity:
Reflex artifact level:
0.001 ml is the lowest detectable volume change
≥95 dB SPL (measured in the 711 coupler, 0.2 ml, 0.5
ml, 2.0 ml & 5.0 ml hardwalled cavities).
Temporal reflex
characteristics:
Initial latency = 35 ms (5 ms)
Rise time = 42 ms (5 ms)