CTP B-MA2 Dual Low-Noise Microphone Preamplifier Beltpack
The CTP B-MA2 Dual Low-Noise Microphone Preamplifier Beltpack is a compact, battery-powered unit containing two broadcast-quality, variable-gain microphone preamplifiers. Level metering and setup are via a bright, crisp OLED display and several configurable options allow tailoring of the unit to a wide variety of broadcast applications.
Standard 3-pin XLR connectors (pin 1 = ground, pin 2 = phase/hot, pin 3 = antiphase/cold) are provided for all audio inputs and outputs.
The outputs are electronically balanced. If an unbalanced output is required then use pin 2 as ‘hot’ and pin 1 as ‘cold. Do not short either pin 2 or pin 3 to pin 1 as this will considerably reduce the life of the battery.
The unit requires either a PP3/6F22-size 9V battery (alkaline types strongly recommended) or an external power supply of nominally 12VDC at 100mA. DC input is via a 2.1mm ‘barrel’ connector (centre pin positive, acceptable range 9-16VDC) compatible with both standard plugs and Cliff twist-locking parts when extra security is required.
During normal operation, the OLED display shows the status of the battery and two pseudo-PPM characteristic bargraph level meters indicating the output level on each channel. When the battery indicator is empty, the battery should be changed as a matter of urgency.
Several features of the B-MA2 may be customised to user preference. To enter Setup mode, hold the front-panel SEL button for approx. two seconds. The OLED display will show the first adjustable parameter and its current value.
Further brief presses of the SEL button will step through the available parameters, eventually looping back to the beginning. When the desired parameter is displayed, use the Up and Down arrow buttons to modify the value of the parameter as required.
To leave Setup mode, hold down the SEL button for two seconds once again. Setup mode will also be automatically cancelled if no button is pressed for ten seconds.
Adjustments made in Setup mode are stored in non-volatile memory and will continue to be applied until changed again. The available options are:
Channel 1/Channel 2 Gain (default value: 30dB)
These set the gain of the microphone preamplifiers. Values from 30dB to 60dB are
available in steps of 3dB.
Ch1/Ch2 Phantom Enable (default value: OFF)
These parameters disable (OFF) or enable (ON) phantom power to the microphone inputs. The phantom voltage is as selected by the corresponding Phantom Voltage option (see below).
Ch1/Ch2 Phantom Voltage (default value: 12V)
These parameters select the voltage used when phantom power is enabled to the corresponding channel. Available options are 12V and 48V – the 12V option should be used whenever possible since the generation of 48V phantom power inevitably has a deleterious effect on battery life.
Mic Highpass Filter (default value: NONE)
An optional high-pass filter can be applied to the microphone signal. Selecting SOME activates a first-order filter with a corner frequency of 100Hz. Selecting LOTS activates a sharper second-order filter with the same cutoff frequency.
81mm wide, 55mm high, 115mm deep including beltclip (removable)
This unit is guaranteed for a period of one year from date of dispatch. This guarantee is a return-to-base warranty. In the unlikely event of a fault the goods should be returned to CTP Systems in the UK or your local dealer.
This equipment is CE marked and conforms (where applicable) to the following directives:
Low Voltage Directive: EN60065 Emissions: EN55103.1 Immunity: EN55103.2
CTP Systems are registered for Business to Business sales of WEEE in the UK. Our registration number is WEE/DF0509VR.
The product conforms to the RoHS Directive 2002/95/EC for restriction of the use of hazardous substances in electrical and electronic equipment.
This unit was designed and manufactured in the UK by CTP Systems Limited