New approachWith the unique transducer combinations G.R.A.S. is introducinga new approach to measurement microphones and to measurement data safety. By analyzing the feedback from our multi- as well as single-channel users we realized that there was a need for a different philosophy when choosing and using acoustic sensors. Daily situations where you mix up externally polarized and prepolarized microphones and preamplifiers or use wrong calibration data in the system setup are time consuming and often undiscovered until a whole set of measurement data is analyzed and consequently discarded. Pre-assembled setsThe Type 46 sets of pre-assembled G.R.A.S. microphonesand preamplifiers solves these situations and is a combination carefully selected to obtain the best possible properties and reliability, thus optimizing the workflow for the user and minimizing typical handling errors. The sets are assembled in a dust-free environment to avoid contamination of the interface between the microphone and preamplifier and have been sealed with a label. The label can be removed and the set dismantled, if desired by the user. Easy selectionThe measurement microphone sets have been combined sothey fulfill our users’ typical measurement needs. Independently of your measurement system and application you should be able to find a set that suits your needs. Use the table on the right to initially identify the input type you have and then choose the appropriate properties for your specific application. Plug & PlayThe microphone sets can be connected directly to all professionalmeasurement systems and as indicated they are available for both CCP and 7-pin LEMO inputs. If your measurement platform supports intelligent transducers according to IEEE 1451.4 (TEDS) you can simply plug in the microphones and they will identify themselves with their specific properties, types and calibration data. A feature especially appreciated by multi-channel users. CablesThe CCP sets use high-quality coaxial cables whereas theLEMO sets use a special, soft type of multi-core shielded cable. Some sets have a 3 m cable included and others have cables as accessories – see the table in the Microphone Sets brochure. It should be noted that longer cables will influence the upper frequency and dynamic ranges. More information about this can be found on gras.dk. Calibration dataAll microphone sets are delivered as a unit and are calibratedaccordingly. The sets are delivered with calibration charts including sensitivity values and frequency response curves for the complete set. The sensitivity value can therefore be used directly in your system setup. Verification and annual calibrationFor frequent verification of the measurement chain, a soundsource will be required. G.R.A.S. supplies a 114 dB sound calibrator for this purpose. Depending on the use and your internal quality control requirements, we recommend that the sets are re-calibrated at least every second year. WarrantyG.R.A.S. offers a 5-year warranty on Type 46 sets.ServiceIf you by mistake should damage the diaphragm, cable, orconnector, they can all be exchanged, which is also the case for the microphone capsule and preamplifier unit. |
