ÌÇa8SÈ-EÇÂ!ÈfeFÎ Calibration Certificate Date of issue 2015-12-08 Calibrated by Gert Schnipper Approved by Ole F. Carlsen 1 (5) CUSTOMER: GN RESOUND A/S GTO LAUTRUPBJERG 7-9 2750 BALLERUP DEVICE UNDER TEST: COMMISSION: EXTENT OF CALIBRATION: MICROPHONE, NTI AUDIO, M2010 Serial No.: 4082 ID No.: - METECH No.: 380020 (MIO No.:) Accredited Calibration NORDTEST: Sound Level Meters: Verification Procedure NT ACOU 068, 1988'; TES_MIKROFON_001_105 STATUS: No adjustment or repair has been made. RESULT OF CALIBRATION: All of the measurements are within the indicated tolerance with a coverage probability of 95%. Layout Edt. 4.22; XL8 Macro Edt. 6.46; BF Macro Edt. 1.70; Print 2015-12-08 11:19:55 Edt. 1 Test template: TES_MIKROFON_001_105 DATE OF CALIBRATION: 2015-11-30 (yyyy-mm-dd) DATE OF RECEIPT: 2015-11-04 (yyyy-mm-dd) LOCATION OF CALIBRATION: Acoustics Laboratory, Lab. 227, 2630 Taastrup AMBIENT CONDITIONS: TRACEABILITY: Temperature: (23 ± 3) C, Humidity: (50 ± 20) %rh The measurement procedures and measurement equipment used have been selected to provide an uncertainty of measurement of less than a third of the specification and to ensure that the measurements are traceable to the International System of Units (SI), where possible. The uncertainty of measurement has been determined in accordance with EA Publication EA-4/02. In the assessment of compliance with specification the uncertainty of measurement has been taken into account. Any statement of compliance with specification is only valid at the tested points. The compliance with specification has been determined in accordance with ILAC publication ILAC-G8:03/2009. Laboratories are accredited by the Danish Accreditation and Metrology Fund DANAK under the terms of Danish legislation. The accredited laboratory activities meet the requirements in ISO/IEC 17025. The Danish Accreditation and Metrology Fund DANAK is one of the signatories to the Multilateral Agreements of the European co-operation for Accreditation (EA) and the International Laboratory Accrediation Cooperation (ILAC) for mutual recognition of calibration certificates and test reports. This calibration certificate may not be reproduced other than in full, except with the prior written approval of the issuing laboratory. Exova METECH A/S, Herningvej 30, DK-7470 Karup Tlf: +45 96 62 50 00, Fax: +45 96 62 50 50, E-mail: service@exovametech.dk CVR-nr. / VAT No: DK 21 49 79 32 The calibration is performed with equipment directly or indirectly traceable to the laboratory reference standards. The reference standards are traceable to national or international standards. CAL Reg. No. 333
2 (5) Reference equipment ID No. Cal. due Pistonphone, Brüel & Kjær 4228 D3206 2016-02-17 Microphone Pre Amplifier, Brüel & Kjær 2673 D3230 2016-05-11 Multimeter, Hewlett Packard 3458A D3228 2016-08-31 Signal Generator, Stanford Research Systems DS360 D3229 2016-09-03 Measuring Amplifier, Brüel & Kjær 2636 D3212 2017-06-15 Actuator Supply, G.R.A.S. 14AA D3243 2016-01-15 Display Unit, Rotronic Hygrolog NT2-D D5445A NCR Humidity / temperature Sensor, Rotronic Hygroclip 2 D5445B 2016-09-01 Pressure Transducer, Keller PAA-33X/80794 D5445D 2016-10-02 Miscellaneous equipment Switch/Control Unit, Hewlett Packard 3488A ID No. D3231 Uncertainty of measurement: The reported expanded uncertainty of measurement is stated as the standard uncertainty of measurement multiplied by the coverage factor k = 2, which for a normal distribution corresponds to a coverage probability of approximately 95%. The standard uncertainty of measurement has been determined in accordance with EA Publication EA-4/02.
3 (5) Compliance with specification: If specification is indicated for a result (measurement), a note will appear. The notes indicate how the results complies with the indicated specification. The compliance evaluation applies for a coverage probability of approximately 95%. P Pass: The result extended with the expanded uncertainty is within the indicated specification. N+ N- The result is within the indicated specification, but the result extended with the expanded uncertainty may exceed the indicated specification. The result exceeds the indicated specification, but the result extended with the expanded uncertainty may be within the indicated specification. F Fail: The result extended with the expanded uncertainty exceeds the indicated specification. NE Test uncertainty ratio (TUR) is not sufficient to evaluate compliance with specification (Not Evaluated). Upper limit Nominal Lower limit P N+ N- F Words/abbreviations that may be used in the certificate/report: NA: Not Available ppm: parts per million UUT: Unit Under Test TUR: Test Uncertainty Ratio DUT: Device Under Test NCR: No Calibration Required
4 (5) Measuring conditions Parameter Reference Value Actual Value Uncertainty Unit Temperature 23 22,7 ±1,0 o C Humidity 50 45,7 ±5,0 %RH Barometric pressure 1013,25 998,8 ±1,0 hpa Sound pressure level 123,97 123,85 ±0,05 db re 20uPa Polarisation Voltage 0 199,99 ±0,10 V 1 Sensitivity The open circuit sensitivity of the microphone was determined at 251,189 Hz with a pistonphone, the sensitivity was measured by insert voltage technique. The measured sensitivity is corrected to 1013,25 hpa barometric pressure. The corrected value also apply for reference conditions 23 C and 50 %RH as deviation and uncertainty due to these conditions is included in the stated uncertainty. Frequency Nominal Measured Corrected Deviation Uncertainty 250 Hz -34,0 db -35,06 db -35,032 db re 1 V/Pa -1,032 db ± 0,20 db 250 Hz 20,0 mv/pa 17,72 mv/pa ± 0,41 mv/pa 2 Frequency response The relative frequency response of the microphone, normalized to 251,189 Hz, is measured at the frequencies given in the table on page 5 with an electrostatic actuator which simulate a sound pressure. The measured response is shown as the green curve with measuring points on the graph. The relative free field frequency response of the microphone is determined by adding the free field correction of the microphone to the measured response. This correction is stated by the vendor and is not standardised. The free field frequency response is shown as the blue curve on the graph. The measuring uncertainty is indicated as the dotted blue curves. The given tolerances are stated by the vendor and apply for the free field frequency response. The given uncertainties apply for the free field frequency response. 4 2 0 0,00-2 Deviation db -4-6 -8-10 -12-14 -16-16, 20 25 31,5 40 50 63 80 100 125 160 200 250 315 400 500 630 800 1,0k 1,25k 1,6k 2,0k 2,5k 3,15k 4,0k 5,0k 6,3k 8,0k 10k 12,5k 16k 20k Frequency Hz
5 (5) 2 Frequency response [Continued] Frequency Measured Corrected Uncertainty Tolerance 20 Hz -1,44 db -1,44 ± 0,50 db -2,0 / 2,0 db P 25 Hz -1,13 db -1,13 ± 0,50 db -2,0 / 2,0 db P 31,5 Hz -0,69 db -0,69 ± 0,50 db -2,0 / 2,0 db P 40 Hz -0,46 db -0,46 ± 0,30 db -2,0 / 2,0 db P 50 Hz -0,26 db -0,26 ± 0,36 db -2,0 / 2,0 db P 63 Hz -0,16 db -0,16 ± 0,30 db -2,0 / 2,0 db P 80 Hz -0,09 db -0,09 ± 0,30 db -2,0 / 2,0 db P 100 Hz -0,02 db -0,02 ± 0,30 db -1,0 / 1,0 db P 125 Hz -0,03 db -0,03 ± 0,30 db -1,0 / 1,0 db P 160 Hz -0,03 db -0,03 ± 0,30 db -1,0 / 1,0 db P 200 Hz -0,02 db -0,02 ± 0,30 db -1,0 / 1,0 db P 250 Hz 0,00 db 0,00 Ref. Ref. 315 Hz -0,01 db -0,01 ± 0,30 db -1,0 / 1,0 db P 400 Hz -0,02 db -0,02 ± 0,30 db -1,0 / 1,0 db P 500 Hz -0,03 db 0,07 ± 0,30 db -1,0 / 1,0 db P 630 Hz -0,04 db 0,06 ± 0,30 db -1,0 / 1,0 db P 800 Hz -0,08 db 0,02 ± 0,30 db -1,0 / 1,0 db P 1,0k Hz -0,12 db -0,02 ± 0,30 db -1,0 / 1,0 db P 1,25k Hz -0,17 db 0,13 ± 0,30 db -1,0 / 1,0 db P 1,6k Hz -0,28 db 0,22 ± 0,30 db -1,0 / 1,0 db P 2,0k Hz -0,41 db 0,19 ± 0,30 db -1,0 / 1,0 db P 2,5k Hz -0,61 db 0,09 ± 0,30 db -1,0 / 1,0 db P 3,15k Hz -0,92 db 0,18 ± 0,30 db -1,0 / 1,0 db P 4,0k Hz -1,36 db 0,34 ± 0,30 db -2,0 / 2,0 db P 5,0k Hz -1,97 db 0,23 ± 0,30 db -2,0 / 2,0 db P 6,3k Hz -2,82 db 0,48 ± 0,30 db -2,0 / 2,0 db P 8,0k Hz -3,91 db 0,29 ± 0,30 db -2,0 / 2,0 db P 10k Hz -5,22 db 0,18 ± 0,50 db -2,0 / 2,0 db P 12,5k Hz -6,93 db 0,37 ± 0,50 db -2,0 / 2,0 db P 16k Hz -8,80 db 0,40 ± 0,50 db -2,0 / 2,0 db P 20k Hz -10,67 db 0,33 ± 0,50 db -2,0 / 2,0 db P 3 Risidual noise The thermal and electrical noise of the microphone and preamplifier is measured A-weighted. Frequency weighting Measured Uncertainty Tolerance A 21,7 ± 0,5 db 24,0 db P End of Document