Advanced High Bias (Maxell XLII-S, Type II) test and calibration audio cassette tape 4 in 1.For mid & high class cassette decks. Content: 1. Left / Right channel check 2. Level: 400Hz (0dB ANSI), 2min3. Speed and W&F: 3000Hz (-10dB), 8 min 4. Azimuth: 15kHz (-20dB), 12 min ! Dolby OFF *This tape was recorded in stereo mode on a reference-tuned Nakamichi deck from digital 88kHz/24bit source. We have different variants of test/calibration tapes.You can find them by clicking this link: "Seller's other items" Dear fans of analog sound! We are glad that our products help you set up your cassette equipment. We enjoy music with you!