4-in-1 AVX30 Test/Calibration audio cassette tape: L/R, level, speed, azimuth

Azimuth: 10kHz (-10dB ANSI), 6 min. Anything with a magnetic field can travel near the tape and disrupt the stability and level of the recording. Left / Right channel check. Speed: 3150Hz (-10dBANSI ), 6 min.

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