Sound Level Calibrator Selector (IEC 60942): Regulated Class 2 Favorite Center 326, PTB-Approved Class 1 Reference & Verified B&K Classics
For every STIPA and PAVA measurement per IEC 60268-16, exact 94.0 dB SPL calibration is mandatory, as SNR and auditory masking penalties are level-dependent. Choose the ideal calibrator for your Bedrock SM50/SM90 test kit—from our best-selling closed-loop favorite to certified authority standards.
When Is Class 1 (PTB Approval) Formally Mandatory?
When inspection codes formally mandate Class 1 precision for your analyzer (e.g., Bedrock SM90 / AM100), you must also use an IEC 60942 Class 1 calibrator (with official pattern approval for legal metrology). A Class 2 calibrator formally degrades the entire measurement chain to Class 2!
When Class 2 Suffices (Physical Reality)
When no formal Class 1 obligation exists (as in standard commissioning with the Bedrock SM50), real-world differences between Class 1 (±0.2 dB) and a closed-loop Class 2 calibrator like the Center 326 are negligible. Crucial is an integrated reference mic with closed-loop feedback, keeping SPL rock-solid at 94.0 dB even with a 1/4" adapter!
Direct Comparison: Which Calibrator Fits Your PAVA Kit?
Sound level calibrator AZ8930 incl. calibration certificate
94 / 104 / 114 dB @ 1 kHz incl. calibration certificate. Budget entry calibrator. Has no internal reference microphone (open-loop) and is sensitive to chamber volume variations. Verified in our lab before shipping.
Sound level calibrator Center 326
True Active Closed-Loop Feedback: Built-in reference microphone in the pressure chamber compensates volume differences (e.g., from adapters or mic geometry) back to exactly 94.0 dB / 114.0 dB.
Lab Precision Near Class 1 Level: In our lab audits, typical level deviation of the Center 326 is under ±0.2 dB—effectively matching Class 1 tolerances in practice.
Lab-Verified Used Class 1 Classics: Brüel & Kjær 4231 (Green), B&K 4230 & Norsonic 1251
For accredited inspectors requiring Class 1 (e.g. on Bedrock SM90): Brand new Class 1 calibrators often cost well above €1,300 net. Our refurbished B&K and Norsonic units were built for decades of service and are individually audited and tuned on our Audio Precision APx555 prior to dispatch.
Second hand Bruel&Kjaer 4230 Sound level calibrator class 1
94 dB @ 1 kHz. Robust analog classic with legendary precision. Includes 1" and 1/2" couplers.
Second hand Bruel&Kjaer 4231 Sound level calibrator class 1
94 dB & 114 dB @ 1 kHz. The worldwide Class 1 reference with internal 200V condenser mic. Exactly what we use on our APx555 test bench!
Second hand Norsonic 1251 Sound level calibrator class 1
114 dB @ 1 kHz. Precision sound calibrator from Norway. Highly stable across frequency and temperature.
Brand New Class 1 Reference Calibrators with PTB Pattern Approval (Microtech Gefell & Svantek)
When your measurement chain requires official verification (weights & measures authorities) or PTB pattern approval is mandated for forensic expert reports, these two instruments are the benchmark.
MTG Microtech Gefell acoustic calibrator class 1 4010
Class 1, PTB approved. Dual-frequency calibrator with 250 Hz & 1,000 Hz at 94 dB & 114 dB. Enables low-frequency response verification in addition to standard calibration.
Svantek SV30A class 1
Class 1, PTB approved. Modern closed-loop MEMS reference system at 1,000 Hz with dual levels (94 dB & 114 dB). High stability against atmospheric pressure and temperature shifts.
Linearity & Low-Frequency Calibrators (AWA Multi-Level & Center 327) plus Calibration Service
For advanced acoustic testing, microphone linearity audits, and annual ISO 9001 calibration.
awa class 1 Mulitlevel 104dB 94dB 84dB 74dB
Class 1 (without PTB approval) with 4 level settings: 74, 84, 94, and 104 dB @ 1 kHz. Ideal for linearity verification across 30 dB dynamic range.
Center 327 multi frequency 125Hz and 250Hz
Multi-frequency Class 2 calibrator for low frequencies: 125 Hz & 250 Hz @ 94 dB. Specifically designed for A/C weighting
Factory & DAkkS Calibration
We calibrate sound calibrators of all brands (B&K, Norsonic, Center, Testo, Voltcraft, Cirrus) on our Audio Precision APx555 reference bench.
Lab Teardown: Why Open-Loop Calibrators Drift When Geometry Changes
A sound calibrator produces sound pressure within a tiny acoustic chamber. If the chamber volume shifts due to capsule geometry or insertion depth, the sound pressure drifts—unless an integrated reference microphone measures the cavity in real-time and regulates the drive voltage.
* All prices in EUR Net excl. VAT and Gross incl. VAT plus shipping costs (FCA Dresden). B2B offer for commercial, government & professional users.