TDM-1911 Automatic Distortion Meter 0.01% - 30% Audio Distortion Meter 110/220V

The residual distortion : greater than or equal to 70 db (distortion than less than or equal to 10 db, input level greater than or equal to 30 mv). Input impedance: 100 k Ω. If the pointer is not zero, but by adjusting the knob of the front panel.

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