TDK D 180 1982 Audio Cassette Test

Testing my old TDK D 180 in a Nakamichi CR-4. I bought it for curiosity but because of the low-hifi sound i never used it for real life. It has been stored long time without use. Tests: 1 Try to calibrate bias and level with internal nakamichi test tone. In normal cases both lines (bias and level) go to 0, it means calibrated optimally). 2. Recording some music. The level down to -20db (max -10 db). No bass and very low high frequencies recorded. Trying dolby B & C dont help. 3 Look the tap