Dayton Audio DATS Dayton Audio Test System - Manual (Page 3)

Figure 2: Impedance Response at Progressively Lower Signal Levels for a Properly Functioning Loudspeaker.
In comparison, Figure 3 shows the same test repeated on a different driver with a rubbing voice coil.
Figure 3: Impedance Response at Progressively Lower Signal Levels for a Defective Loudspeaker.
DATS Accuracy and Precision:
The Dayton Audio Test System, DATS, sets a high standard for speed, accuracy, and precision in
audio impedance testing and loudspeaker parameter measurement. While the unofficial accuracy
specification for DATS impedance measurements is +/- 2%, the product actually performs much
better than this and is limited primarily by the 1% tolerance of the calibration resistor. Basic accuracy
and repeatability (precision) test results for six randomly selected DATS units are given in
Appendices A through F. A summary of the results is given in Figure 4 and shows a worst case error
of -2.179% at 1 Ohm compared to error under 0.5% at higher frequencies. The error at 1 Ohm may