Single-channel vintage style microphone-, line- and instrument preamplifier with signal path that uses only discrete components like resistors, tantalum capacitors and transistors, no integrated circuits. The input and output are transformer balanced, using two different transformers, each one optimized for its purpose. The circuit used in the preamplifier is similar to the preamp section in the classical 1073 module with a corresponding sound character that is warm, punchy, sweet and musical. These classic characteristics have been heard on countless recordings through the years and it is a versatile sound that works very well on most sound sources and in most genres. Maximum gain in MIC mode is 80 dB, enough to handle passive ribbon mics with quiet sound sources, while GAIN switch range is 20 - 80 dB. With GAIN/LINE mode switch, gain is reduced by 30 dB in LINE mode. The preamplifier further provides selectable two position high frequency AIR boost EQ, 3 or 6 dB @ 30 kHz; selectable 6 dB/octave two frequency high pass filter at around 40 (HP1) and 170 Hz (HP2); switchable impedance in MIC mode (1200 or 300 Ohms) that will change the tone of most mics. The input impedance in LINE mode is 10 kohm. Other features include switchable phantom power and absolute phase; a high-impedance instrument input for any sound module, electric guitar or bass; and a simple but effective 4-step LED output level meter. The output level control makes it possible to make fine gain adjustments and also to overload the main gain stage(s) for more character and then lower the signal to a suitable level before the output stage. Combo XLR/TRS input jack and separate output XLR and TRS jacks are provided for flexible connections, as well as an insert jack for inserting EQ´s and other units. The circuit board is prepared for the Carnhill input transformer. The unit is powered by an external power supply to avoid interaction with the audio circuits and transformers.
Vattensporter
se
