GRAS 12AK 1-Channel Power Module with gain and filters
Connection: Traditional 200 V
Channel(s): 1
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.
Technology
Typical applications and use
-
General-purpose measurements
-
Precision measurements
-
Acoustic monitoring
-
Microphone calibration
Design
It has the following signal-conditioning settings:
-
linear-response
-
A-weighting
-
high-pass filtering
The 12AK can be powered either by internal standard batteries or an external DC supply (12 V - 18 V), e.g. a mains/line adapter. It is built into a sturdy anodized aluminium cabinet.
The polarization voltage for the microphone fitted to the preamplifier can be set to 0 V — for prepolarized microphones, or 200 V — for externally polarized microphones. The voltage supply for the preamplifier can be set to 120 V — for maximum dynamic range, or 28 V — for minimum power consumption.
The 12AK will run for approximately 11 hours on fresh standard alkaline batteries. A Low Batt LED indicates the condition of the batteries.
The input is a 7-pin LEMO socket on the front panel which is wired up for GRAS microphone preamplifiers, e.g. 26AB, 26AC, 26AJ and 26AK, but is also compatible with other available makes of similar microphone preamplifiers.
The output is a standard BNC connector also on the front panel.
There are two overload indicators; one instantaneous, and one latched which can be reset. The gain can be set from 0 dB to + 50 dB in steps of 10 dB.
The standard A-weighting filter complies with IEC Standard 60651: Sound level meters Type 0. The high-pass filter is a 3-pole Butterworth filter with a –1 dB cut-off at a frequency of 20 Hz. This filter is for reducing unwanted low-frequency signals, e.g. caused by wind-induced noise on the microphone.
The preamplifier signal can be coupled directly to the output of the 12AK by selecting direct output. This makes the output of the preamplifier available free of any signal conditioning.
The cabinet of the 12AK is 1/12 of a standard 19-inch rack; meaning that up to 12 of these Power Modules can be mounted in a standard 19-inch rack using the AK0040 Rack-mounting System.
Warranty
All GRAS products are made of high-quality materials that will ensure life-long stability and robustness. The 12AK is delivered with a 2-year warranty. The warranty does not cover products that are damaged due to negligent use.
Service and Repairs
All repairs are made at GRAS International Support Center located in Denmark. Our Support Center is equipped with the newest test equipment and staffed with dedicated and highly skilled engineers. Upon request, we make cost estimates based on fixed repair categories. If a product covered by warranty is sent for service, it is repaired free of charge, unless the damage is the result of negligent use or other violations of the warranty.
Specifications
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.
Ordering info
Included
| GRAS EL0001 | 10 x LR6 (AA) alkaline cells |
| GRAS AB0002 | DC mains/line adapter, Europe |
| GRAS AB0003 | DC mains/line adapter, USA |
Optional
| GRAS AK0040 | 19˝ Rack mounting System |
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.
