User`s manual

Pressing OK we get Fig.13.15 which is our final result. Note that the Y Units have
been changed to Ohm. This result is only in memory and should be saved now for
further use.
Audiomatica Srl Sinusoidal 04/07/2001 10.52.16
CH A dBV Unsmoothed Stepped Delay [ms]: 0.000 Dist Rise [dB]: 30.00 File: cvresult.sini
10 100 1k 10k 20k10 Hz
50.0
Ohm
180.0
Deg
40.0 108.0
30.0 36.0
20.0 -36.0
10.0 -108.0
0.0 -180.0
CL IO
Figure 13.15
13.5.2 CONSTANT CURRENT
We will go quicker now as it’s very similar to what we have just seen. Connections
for creating the reference are the same, please refer to Fig.13.11. Again everything
should be left unchanged between creating the reference and the device files. The
big difference from before is the output level. Here we choose a 1kOhm resistor.
This will attenuate a lot of the signal at the loudspeaker terminals. Fig.13.16 shows
the reference measurement.
Audiomatica Srl Sinusoidal 04/07/2001 11.29.26
CH A dBV Unsmoothed Stepped Delay [ms]: 0.000 Dist Rise [dB]: 30.00 File: cireference.sin
10 100 1k 10k 20k10 Hz
30.0
dBV
180.0
Deg
20.0 108.0
10.0 36.0
0.0 -36.0
-10.0 -108.0
-20.0 -180.0
CL IO
Figure 13.16
We have a straight line again; notice the level has became 17dBV now. We change
connections, in accordance with Fig.13.17, and nothing else.
13 MEASURING IMPEDANCE AND T&S PARAMETERS 189