JBL SG-520 (s/nr 1793) is in very good condition and fully operational. My dad and I purchased it new ca. 1967-68 and it has been well cared for and maintained since then. Operationally tested last week of August 2014; inputs and outputs work well: low-noise, very clean sound. The linear controllers (potentiometers) are smooth and noise-free . . . no scratching or clicks as the pots are moved. Slight marring of a few silk-screen legends on rear panel Does not include manual but plenty of data on it available on-line (please see photos!).
[Package option: This SG-520 purchased with stereo pair of JBL Lancer LE-2-99 speakers with JBL SE-408S \"Solid State Transducer Energizer\" (s/nr 1103). The SE-408S power amp is 2 x 40 RMS 20Hz - 20kHz. See listing and photos on via keyword search. Package price for all is available.]

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