CLIOwin 7 PCI User's Manual - Audiomatica

If you are a novice in using CLIO, or to impedance measurements in general, use this
mode; also do not start measuring loudspeaker impedance immediately. Get a 22 to
100 Ohm resistor, possibly 1% tolerance, and gain experience with something which
you should already know the expected results of. Here are two examples both with
Sinusoidal and MLS. Before you press go, remember to set the Y scale to Ohm. For this
example we chose a 47 Ohm resistor. The modulus should be very close to the resistor
value (red curve) and equally important, the shown phase should be very close to 0;
these results should cover the entire frequency range. Notice that Fig.13.3, which refers
to MLS, extends low frequency limit to 1Hz while Sinusoidal, Fig.13.2, stops at 10Hz
which is the lowest possible. If you are not getting similar results do not proceed with
a loudspeaker impedance measurement. To do so would only add problems later by
using an inaccurate working procedure, as we will soon see. Even in internal mode CLIO’s
output level is left to the user. We set it at +10dBu here as resistors are, hopefully, the
most linear devices we can get. Since we had very comfortable results lets proceed with
a Loudspeaker.
50.0
CLIO
180.0
50.0
CLIO
180.0
Ohm
Deg
Ohm
Deg
40.0 108.0
40.0 108.0
30.0 36.0
30.0 36.0
20.0 -36.0
20.0 -36.0
10.0 -108.0
10.0 -108.0
0.0 -180.0
10 Hz
100 1k 10k 20k
0.0 -180.0
1 Hz
10 100 1k
Figures 13.2 and 13.3
158 Chapter 13 - Measuring impedance and T&S parameters