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AUDIO GENERAL AGI 511 Preamplifier! RARE in Black finish, Excellent Condtion A++

Used, Tested, & Working. Excellent overall condition with just minor flaws (SEE PICTURES)

There is some tape residue on the top cover.

Specifications (typical for 1977–1986 models)

Frequency response: 20 Hz – 20 kHz
Total harmonic distortion: 0.005%
Signal-to-noise ratio: 88 dB (MM)
Gain: 33 dB (MM), 18.7 dB (line)
Dimensions/weight: ~354 × 132 × 243 mm / 6 kg
Inputs: RCA line, phono, tape inputs, aux, mono, tone controls, balance, volume
Power: 105–130 V, 50–60 Hz, 5 W

Due to its single‑model production and limited numbers, the AGI 511 is a collector’s item. Units are rare, and many owners keep them in storage rather than sell. In good working condition, they can command high prices in vintage audio markets.

Bottom line: The AGI 511 is a rare, audiophile‑grade preamp with exceptional build quality, neutral yet warm sound, and a reputation for being one of the best preamps of its era. If you find one, it’s worth restoring and using in a high‑end system — but expect it to be a long‑term investment.