Calibration of testing equipment in an anechoic chamber is an important task to ensure the accuracy and reliability of test results. The following is the general process for calibrating testing equipment in anechoic chambers:
 
1. Preparation work
 
1. Equipment inspection: Ensure that all testing equipment (such as microphones, sound level meters, audio analyzers, etc.) are in normal working condition.
2. Environmental preparation: Confirm that the sound-absorbing materials and sound insulation facilities in the soundproof room are intact and undamaged, ensuring that the indoor environment meets the testing requirements.
3. Calibration standards: Prepare relevant calibration standards and specification documents, such as JJF1147-2006 "Calibration Specification for Acoustic Characteristics of Anechoic Chambers and Semi anechoic Chambers".
 
2. Calibration steps
 
1. Initial calibration: Use a known standard sound source to perform initial calibration on the testing equipment. Place the standard sound source in the center of the anechoic chamber, activate the sound source, and record the readings of the testing equipment.
2. Path calibration: For testing equipment that requires moving the microphone, use an automatic measuring device for path calibration. Ensure the linearity and stability of the path when the microphone moves along the predetermined path.
3. Frequency response calibration: Use standard sound sources of different frequencies to calibrate the frequency response of the testing equipment. Record the sound pressure level readings at each frequency point and plot the frequency response curve.
4. Sound pressure level calibration: Use standard sound pressure level signals to calibrate the sound pressure level of the testing equipment. Compare the readings of the testing equipment with the standard values and make necessary adjustments.
5. Spatial characteristic calibration: For testing equipment that needs to measure spatial acoustic characteristics, perform spatial characteristic calibration. Record sound pressure level readings at different locations and plot spatial characteristic curves.
 
3. Data analysis and adjustment
 
1. Data recording: Detailed recording of each calibration data, including readings of testing equipment, standard values, environmental conditions, etc.
2. Data analysis: Analyze calibration data, calculate the error range of testing equipment, and determine whether it is within the allowable error range.
3. Equipment adjustment: Based on the data analysis results, necessary adjustments are made to the testing equipment to ensure the accuracy and reliability of its measurement results.
 
4. Calibration report
 
1. Report writing: Write a detailed calibration report, including calibration objectives, methods, steps, data analysis results, equipment adjustments, etc.
2. Report review: Submit the calibration report to relevant departments for review to ensure the accuracy and completeness of the report content.
3. Report archiving: Archive the approved calibration report for future reference and reference.
 
5. Regular calibration
 
1. Develop a calibration plan: Based on the frequency and importance of using the testing equipment, develop a regular calibration plan.
2. Implement calibration plan: Regularly calibrate the testing equipment according to the calibration plan to ensure that it maintains good working condition for a long time.
 
Conclusion
 
The calibration of testing equipment in soundproof rooms is a complex and meticulous task that requires strict adherence to relevant standards and specifications. Through regular calibration, the measurement results of testing equipment can be ensured to be accurate and reliable, thereby improving the quality and efficiency of testing work. I hope the above information is helpful to you. If you have any other questions, please feel free to continue asking.