Power modules
Why a Power Module?
An externally polarized condenser measurement microphone cannot work on its own. It needs to be connected to hardware that can act as an interface between the raw signal output and the data acquisition unit or measurement device. The Power Module is such an interface that improves the performance and reliability of the measurement chain.
- It provides polarization voltage for the transducer, ensuring that the microphone gets the charging voltage it needs.
- It provides supply voltage for the microphone preamplifier. The preamplifier acts as a unity gain impedance converter. It provides a certain amount of line drive capability by providing a low output impedance and output current, making it possible to transmit the signal from the transducer to the Power Module without significant degradation.
- A power module can provide amplification or attenuation to the signal, thus making it possible to fine tune the measurement chain to the signals being measured and the hardware being used.
- Selectable filters make it possible to exclude unwanted noise from the measurement, e.g., wind-induced noise from outdoor measurements.
- Overload detection makes it possible to validate the measurements and is a useful tool in monitoring setups.
- When a Power Module with gain is used, you can use longer cables because of the power module's ability to deliver current.
- A Power module introduces electrical isolation
GRAS' range of power modules cover solutions for electroacoustic applications (LEMO), intensity probes (LEMO), lownoise microphones (LEMO) and power modules with traditional power supply (LEMO) as well as power modules with constant current power (CCP) that have the ability to take advantage of GRAS SysCheck2™-enabled microphones.
Connection: Traditional 200 V / CCP
Channel(s): 1
GRAS 12AU 1-Channel Universal Power Module with signal conditioning and power amplifier
The GRAS 12AU is a supply and conditioning amplifier for simultaneously powering a preamplifier for a condenser microphone and an amplifier for a loudspeaker. It is ideally suited for automated production line testing of micro speakers and mobile devices with built-in speaker.
Connection: Traditional 200 V
Channel(s): 6
GRAS 12AC 6-Channel Power Module for GRAS Vector-intensity Probe
GRAS 12AC 6-Channel Power Module for GRAS Vector-intensity Probe
Connection: Traditional 200 V
Channel(s): 1
GRAS 12HF 1-Channel Power Module for Low-noise Systems
The GRAS Power Module 12HF is a power supply for single-channel, low-noise measurements using the matched, low-noise preamplifiers and high-sensitive microphones of a GRAS low-noise measuring system 40HF, 40HH or 40HT.
Connection: Traditional 200 V
Channel(s): 10
GRAS 12HM 10-Channel Power Module for Lownoise Systems
The GRAS Power Module 12HM is a 10-channel power supply for multi-channel lownoise measurements using the matched, low-noise preamplifiers and high-sensitive microphones of a GRAS 40HF, 40HH or 40HT Lownoise Measuring System.
Connection: CCP
Channel(s): 1
GRAS 12AL 1-Channel CCP Power Module with A-weighting filter
The GRAS 12AL CCP (Constant Current Power) Supply is a low-noise single-channel power supply for CCP transducers and preamplifiers.
Connection: Traditional 200 V / CCP
Channel(s): 2
GRAS 12AQ 2-Channel Universal Power Module with signal conditioning and PC interface
The GRAS 12AQ Power Module is a dual-channel power supply for preamplifiers (CCP as well as traditional) used with measurement condenser microphones.
Connection: CCP Channels: 4
Gain: 0, 20, 40 dB
GRAS 12AX 4-Channel CCP Power Module with Gain
The GRAS 12AX CCP (Constant Current Power) Supply is a low-noise 4-channel power supply for CCP microphone sets.
Microphone power: CCP
Channel(s): 1, 2, or 4
TEDS via USB
GRAS 12BA, 12BE and 12BB CCP Power Modules with TEDS Support
12BA, 12BE and 12BB are 1-, 2- and 4-channel CCP power modules, respectively. They have SysCheck2™ and TEDS support and are powered by USB.
Connection:Traditional 200 V
Channel(s): 2
GRAS 12AA 2-Channel Power Module with gain and filters
The GRAS 12AA Power Module is a dual channel power supply for preamplifiers used with condenser microphones. It is for general use in acoustic measurements as well as for intensity measurements; both in the laboratory and in the field.
Connection:
Traditional 200 V
Channel(s): 1
GRAS 12AD 1-Channel Power Module
The GRAS 12AD Power Module is a single-channel power supply for preamplifiers used with condenser microphones. It is for general use in acoustic measurements; both in the laboratory and in the field.
Connection: Traditional 200 V
Channel(s): 8
GRAS 12AG 8-Channel Power Module with gain and filters
The GRAS Power Module 12AG is an 8-channel power supply for preamplifiers used with condenser microphones. It is for use in multichannel acoustic measurements in both laboratory and field.
Connection: Traditional 200 V
Channel(s): 1
GRAS 12AK 1-Channel Power Module with gain and filters
The GRAS 12AK is a single-channel power module with a 7-pin LEMO 1B connector for power and polarization of an externally polarized microphone set. It features instantaneous and latched overload indication, adjustable gain settings, A-weighting, and Lin and HP filters. These features make the 12AK the ideal choice for a wide range of applications such as monitoring, laboratory use, and sound level meter measurements.
Connection: Traditional 200 V
Channel(s): 4
GRAS 12AN 4-Channel Power Module
The GRAS 12AN 4-Channel Power Module is a four-channel power module with 7-pin LEMO 1 B connectors for externally polarized measurement microphone sets. The inputs are AC-coupled directly to the outputs for a flat frequency response down to 0.05 Hz. It provides the basic features for powering condenser measurement microphones. The polarization voltage can be selected to 200 V for externally polarized microphones or 0 V for prepolarized microphones. The supply voltage for the preamplifiers is ±15 V.
Connection: Traditional 200 V
Channel(s): 2
GRAS 12AR 2-Channel Power Module
The GRAS 12AR Power Module is a dual-channel power supply for preamplifiers used with condenser microphones. It is for general use in acoustic measurements; both in the laboratory and in the field.
Connection: LEMO
Traditional 200 V
Channel(s): 1, 2 or 4
TEDS via USB
GRAS 12BC, 12BF and 12BD LEMO Power Modules with TEDS Support
GRAS 12BC, 12BF and 12BD are 1-, 2- and 4-channel LEMO power modules, respectively. They have TEDS support and can be powered by USB or AC mains.
