User manual ART PRO MPA

[. . . ] A R TÕs PRO MPA circuitry is a hybrid design utilizing the latest and most advanced solid state and tube technology. Using a transformerless design throughout, the PRO MPA maintains exceptional signal integrity and extremely low noise. The Active balanced input utilizes a hybrid, triple-differential transistor design, providing extremely low noise and excellent CMRR. A second stage 12AX7A tube running on a regulated DC voltage provides an additional 40 dB of gain. [. . . ] **Note: Be sure to turn down or mute the output of the PRO MPA when engaging or disengaging Phantom power. Additionally, when disengaging, allow 30 - 45 seconds for the power to completely dissipate. Most microphones will make a sound like air leaking from a tire when phantom power is disconnected, but some can make some very nasty low rumbles and whines as well. **Another Note: Dynamic microphones should not be affected or damaged if they are plugged into a line where Phantom FRONT PANEL CONTROLS & INDICATORS Power The Power switch supplies and removes power from the unit. The PRO MPA should be powered ÒonÓ with all monitor levels turned down, or off, to protect against any ÒthumpingÓ caused by high gain settings. Likewise, the PRO MPA should be turned ÒoffÓ after turning all monitor levels down. Input Level Control The Input Level Control sets the amount of input gain of the PRO MPA. Turn the control clockwise to increase gain and counterclockwise to decrease gain. You may control two ranges of gain with this control, +26 to +60dB and +6 to +40dB. When setting the Input Level Control, refer to the 10 segment Tube Character Array for a visual reference to the PRO MPAÕs internal signal levels (applied gain). Output Level Control The Output Level Control sets the output level of the PRO MPA. Turning the control clockwise increases the level of the output to a maximum of +10dB of gain. When setting the Output Level Control, refer to the Vu Meter for an accurate level leaving the PRO MPA. +20dB Gain/ Norm Switch Use the +20dB Gain/ Norm switch to set the gain range of the Input control. When the switch is in the out (Normal) position the gain range is +6 to +40dB. With most microphone applications youÕll find using the 6 7 power is present. HPF (High Pass Filter) Control The HPF is a low frequency roll-off intended for use to Òtune outÓ unwanted rumbling or breath noises. A High Pass Filter allows frequencies above its set point to pass unaffected while gently rolling off frequencies below its set point. The range of the PRO MPAÕs HPF is 7Hz to 150Hz with a slope of 6dB per octave. This gentle slope allows unwanted low frequency information to be rolled off while not affecting the tonality of the input signal. In its fully counter-clockwise position, the filter has a set frequency of 7Hz which can be considered ÒbypassedÓ or off. The filter is located after the Input Level Contol and before the tube circuitry. [. . . ] 215 Tremont Street Rochester, NY 14608 Atten: Repair Department R. A. # _______________ 7) Contact our Customer Service department at 716/436-2720 for your Return Authorization number or questions regarding your repair. Customer Service hours are Monday through Friday 8:30AM to 4:30PM Eastern time. A R T PRO MPA SPECIFICATIONS Dimensions: Input Connections: Output Connections: Input Impedance: XLR, 1/4Ó Output Impedance: XLR, 1/4Ó Maximum Input Level: XLR Maximum Input Level: 1/4Ó Maximum Output Level: XLR Maximum Output Level: 1/4Ó CMRR Frequency Response Dynamic Range Total Harmonic Distortion(THD) Maximum Gain: XLR to XLR Equivalent Input Noise (EIN) XLR to XLR (shorted input) Power Requirements: 3. 50Ó H x 19Ó W x 6. 5Ó D XLR (balanced), 1/4Ó unbal. 1. 67k ohms, 840K ohms 600 ohms, 300 ohms +17dBu +20dBu +28dBu +22dBu >90dB (typical @ 1kHz) 20Hz to 40kHz (+0, -1dB) >100dB (20Hz to 20kHz) <0. 1% (typical) >72dB >-124dBu unweighted >-133dBu (ÔAÕ weighted) 100-125VAC, 25W - (USA) Internal fuse. Other power require ments configured for country of desti nation. A R T retains a policy of constant product improvement. [. . . ]