Nagra IV-SJ - Stereo Nagra for instrumentation and logging. Pots are replaced with selectors to set gain in precise steps, no limiters, and when present, the microphone inputs are for high-voltage unbalanced instrumentation mics rather than low impedance balanced with T-power and phantom. Amazing frequency response specification of 25 Hz to 35 kHz at 15 ips-38 cm/s, Wow and flutter: 0.05% (15 ips).
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