The Golden Age Project PRE-573 Premier is a one-channel microphone, line, and instrument preamplifier that offers the classic vintage sound of the 1073 preamp in the convenient form of a 500 series module. The signal path uses only discrete resistors, capacitors, and transistors, while the microphone and line inputs and the line output are transformer balanced, using two different transformers—each one optimized for its stage in the signal chain.
The circuit used in the PRE-573 Premier is similar to the preamp section in the classic 1073 module, producing a warm, punchy, sweet, and musical sonic character—especially useful for livening up today's digital recording chains with analog flavor. The unit sports a classic grey front panel with a red gain knob, metal switches, and a gray metal output level knob.
- The unit features vintage-style electronics, with no integrated circuits in the signal path.
- With a UK-made Carnhill input and output transformer, the balanced, fully floating output can drive a 600-ohm load up to level of about 28 dBu.
- Maximum gain in MIC mode is 80 dB, enough to handle passive ribbon mics with quiet sound sources.
- The total gain range goes from -10 to +80 dB. The 20 to 70 dB range (in MIC mode) is handled by a turn switch and a toggle switch that together select an additional 5 or 10 dB gain.
- Switchable impedance on the mic input, 1200 or 300 ohms, will change the tone of many microphones.
- The input can be configured to accept line level signals by another switch, the level is then lowered by about 30 dB and the input impedance increased to about 10 kilohms.
- A selectable two-position 6 dB / octave highpass filter with frequencies of approximately 45 and 180 Hz.
- A flexible front-panel instrument input for electric guitar or bass that can be switched between a high impedance active or a Mid-Z passive mode. These two DI-options make it possible to get different tones from instruments. Mains-connected sound modules or other signal sources should be connected to the mic/line input of a 500 series rack unless they have a fully floating transformer-balanced output stage.
- The output level control makes it possible to make fine gain adjustments, to overload the main gain stage(s) for more character, and to lower the signal to a suitable level before the output stage.
- An insert jack lets you insert Golden Age Project and Premier 500 Series EQ and effect units. The insert is activated by removing a jumper at the back of the module.
- A soft start circuit ramps up the supply voltage slowly (~10 sec.) to avoid a power-on current surge.
- A phase switch and switchable phantom power with a LED indicator are on board.
- Selectable Air equalizer adds a boost of approximately 6 dB centered at 30 kHz.
- A single LED that starts glowing red at about +4 dBu and then increases its intensity up to the maximum output level, serving as a simple but effective signal and overload indicator.
- Tantalum and polystyrene capacitors are used in the traditional positions.
- The 6.8-kilohm phantom-power resistors are matched to within 0.1% to maintain good common-mode rejection in the circuit.
- The module features a selectable 600-ohm output termination in the back.
- The unit uses a circuit board star grounding scheme.
- A rugged build quality ensures long-term performance.