Microphones & Preamplifiers Calibration

Primary Calibrations

HBK hosts in Copenhagen the Danish Primary Laboratory of Acoustics (DPLA) that calibrates reference microphones with reference to DFM – Danish National Metrology Institute.

The calibration laboratory for primary calibrations is accredited by the Danish accreditation body – DANAK.

A calibration includes the following measurements:

• Visual inspection
• Sensitivity measurements
• Frequency response (TBV)

The calibration certificate specifies the measurement uncertainty.

Accredited Calibration

Accredited calibrations are performed in service centers accredited by the local accreditation bodies according to EN ISO/IEC 17025 standards. This proves the traceability back to the International System of Units (SI).

A calibration includes the following measurements:

• Visual inspection
• Sensitivity measurements
• Frequency response

The calibration certificate specifies the measurement uncertainty.

Local Calibration Services

For service centers without accreditation for microphones, local calibration services are offered. Often, it is the same calibration as performed in accredited laboratories – just without the logo of the accreditation body.

In some countries, additional legal verification is required by local authorities. A range of these verifications can be done in HBK service centers.

We can provide the following types of accreditation for HBK measurement microphones and microphone preamplifiers:

• DANAK (English certificate)
• A2LA (English certificate. Includes frequency response curve)
• DAKKS (German certificate)
• COFRAC (French certificate)
• ENAC (Spanish certificate)
• NATA (English certificate)

Initial Calibration

Most types of microphones from HBK are delivered with the manufacturer’s measured calibration data. To start the accredited calibration history from day one, we recommend that you take advantage of our accredited-calibration services when you purchase your new microphone and preamplifier.

Re-Calibration

HBK recommends annual re-calibration to provide data for an unbroken calibration history to use as a reference, either for internal requirements, for auditing required by authorities or at the request of your customers. The shorter the period between calibrations, the lower the risk of questionable measurements.

For non-TEDS microphones, we recommend you include your preamplifier to ensure there is no unknown deviation in your instruments.

Measurements

Calibration of microphones is performed at 250 Hz. Measurements are conducted according to IEC 61094 and to the manufacturer’s specifications.

For TEDS microphones, the calibration values are loaded into the microphone.

Accredited calibration with frequency response is available with an A2LA certificate.

Measurements are traceable to institutions such as DPLA, NIST, NPL and PTB.

Certificate

With the certificate you receive:

• Proof that calibration has been performed according to the quality requirements in ISO 17025 
• Measured uncertainty
• Internationally accepted documentation with the logo of the accreditation body
• Calibration conditions: air temperature, air pressure, and relative humidity.