20 dB Attenuator for use between 1/2″ preamplifier and microphone.
Microphone attenuators are placed between the microphone and the preamplifier in order to extend the maximum sound pressure level a Sound Level Meter can measure. The maximum sound pressure level a Sound Level Meter can measure is either determined by the microphone or the electrical performance of the Sound Level Meter. In the latter case a microphone attenuator will prove useful, as it will prevent the microphone output voltage from overloading the microphone preamplifier or the input amplifier stage of the Sound Level Meter.
The microphone attenuator will not change the maximum sound pressure level the microphone cartridge itself can measure.
The microphone attenuator Nor1260 provides about 20dB attenuation when used with a 1/2″ microphone. All attenuators are individually calibrated.
This adaptor adapts a 1/1″ microphone to a 1/2″ preamplifier.
This adaptor adapts a 1/2″ microphone onto a 1/4″ preamplifier.
The adaptor has not an integral guard ring. Hence, the adaptor adds a small attenuation to the microphone sensitivity. The Nor1280 adaptor has the same function as the Nor1276, but with guard ring to ensure a minimum attenuation added to the microphone sensitivity.
The Nor1276 adaptor is included as a part of the Nor1204, 1/4″ preamplifier kit.
1/4″ preamplifier to 1/2″ microphone adaptor with guard ring.
This adaptor has a true 1/2″ preamplifier configuration. This ensures that you can connect a 1/2″ microphone to a 1/4″ preamplifier with negliable loss in sensitivity. The unique construction of the adaptor extend the guard ring from the 1/4″ preamplifier to a true 1/2″ preamplifier with guard ring.
It is mainly used in application that requires a high degree of accuration, such as calibration laboratories and intensity probes etc.
Preamplifier extension cable Nor1408A comes with Lemo connectors to fit directly in the measurement chain. The contact pins are gold plated and the connector housing is protected with a special rubber sleeve. This protects the connectors in use from moisture, dirt and bumps. The Nor1408A replaces the Nor1408. The A version is similar to the 1408 but has in addition added threads on the outer shell of the female connector to fix the lock ring on a Nor1206 and Nor1209 preamplifier. The cable is a general purpose cable suited for all preamplifiers following the Lemo 1B standard developed by Norsonic, such as Nor1201, Nor1203, Nor1204, Nor1206 and Nor1209 as well as preamplifiers of other brands.
Standard lengths are 5, 10, 20, 30 and 50 metre. Special lengths on request. The /xx in the order code denotes the lenght of the cable.
Nor1408WW
This cable is designed for fixed installations in test chambers. It has the same pinout as a standard Nor1408 cable.
A small cable drum for maximum 20 metre cable.
Norsonic cable drums are available in two different sizes. Both drums have a small reel attached to the main reel that holds one end of the cable, approximately 2 metres, needed for attaching the cable from the drum to the measuring equipment. The cable can easily be removed from the drum without disassembling it.
A large cable drum for cable lengths up to 150 metre.
Norsonic cable drums are available in two different sizes. Both drums have a small reel attached to the main reel, that holds one end of the cable, approximately 2 metres, needed for attaching the cable from the drum to the measuring equipment. The cable can easily be removed from the drum without disassembling it.
Preamplifier cable Nor1410A comes with Lemo connectors to fit directly in the measurement chain. It features high quality connectors with gold plated contact pins. The Nor1410A replaces the Nor1410. The A version is similar to the 1410 but has in addition added threads on the outer shell of the female connector to fix the lock ring on a Nor1206 or Nor1209 preamplifier. The cable is a general purpose cable suited for all preamplifiers following the Lemo 1B standard developed by Norsonic, such as Nor1201, Nor1203, Nor1204, Nor1206 and Nor1209 as well as preamplifiers of other brands.
Standard length is 2 metre. For special length see Nor1408A.
Nor1438 is a BNC to Lemo cable.
Having a length of 2 metres, this cable is a 3 mm thin and flexible cable with BNC connector in one end and a Lemo male in the other end. For connection of an electrical signal to a measuring instrument using Norsonic Lemo system.
The line input adaptor Nor1447 provides a BNC line connection to a ½” preamplifier such as Nor1201. The main application is for connecting an electrical signal to a microphone preamplifier. But it may also be used to connect a transducer like an accelerometer to the high impedance input of a microphone preamplifier or as a “dummy microphone”. A built in screened capacitor in series with the line signal prevents the polarisation voltage from damaging the line signal source (Except from the Nor1447/S). The attenuation of the signal is small due to the design with use of a screened capacitor that is connected to the preamplifiers guard ring. The most popular version is the Nor1447/2 that has a capacitance equal to a ½” microphone. Other versions with other capacitance are available. Please note that all versions are for connection to a 1/2″ preamplifier. Each unit is individual calibrated with calibration certificate for the capacitance (Except from Nor1447/S).
The following versions are available:
Nor1447/S – Direct connetion without serial capacitor
Nor1447/L – Low input capacity version C=2pF or C=6.8pF
Nor1447/2 – Replaces a 1/2″ microphone load. C=18pF
Using the Nor1447 as Microphone Equivalent – “Dummy microphone”
A microphone equivalent is mainly used to determine the electrical self noise of a sound level meter. The microphone is replaced by the microphone equivalent. As the microphone equivalent has impedance similar to that of the microphone cartridge, but no sensitivity to the acoustic field, the level displayed on the sound level meter will be the electrical self noise of the sound level meter including the preamplifier.
The capacitor used in the Nor1447 is a high quality type to minimise the microphone effect of the capacitor.
All units (except from /S and /L) are delivered with a BNC shortage plug included. The 1447/x with a BNC shortage plug connected equals to a microphone equivalent.
The method is not usable for measurement of the thermodynamic noise of the microphone cartridge.
