Retro Instruments 500 Pre The Retro Instruments 500Pre design purposely has the limiter effect of tube amplifiers. The Retro 500-PRE works within API 500 rack power limitations. The Retro 500 PRE uses three 12AT7 tubes that are readily available as new production or new-old-stock. A user can select from a wide variety. Your unit uses the new production TAD 12AT7 and these tubes are expected to last for a very long time under the 500PRE operating conditions. We use soft-start circuitry that minimizes stress to the tubes and power supply. The 500PRE takes less than a minute to warm up and perform.Each 500 PRE consumes 160 ma of power, slightly above the 130 ma VPR-compliant allocation. We recommend racks with quiet linear power supplies like the API models. When power requirements are observed, the rack and 500PRE will provide years of reliable service. Specifications Front Panel Controls: Input Level, Gain Select (two or three stage amplifier), Phantom Power, Polarity, and Output Level. Input and Output Connections: On edge card connector for 500 rack XLR. Gain: 48 dB (low gain two stage topology) 76 dB (high gain three stage topology) Total Harmonic Distortion: 1000 Ohms from 20-20000 Hz. Output Impedance: 600 Ohms Transformer Balanced. Power Consumption: +/-16 Volts 155 ma. 48 Volts 3 ma. Weight: 2 lbs 7 oz.
