User`s manual

Table Of Contents
11.3 HOW TO MEASURE A SIMULTANEOUS FREQUENCY AND
IMPEDANCE RESPONSE OF A LOUDSPEAKER
ISenseIn1 D.U.T.
QCBox
OUT A
CLIO
IN A OUT BIN B
Mic
Speaker
CLIOIn2 In3 In4
To From
CLIO
Using the ISense current sensing output of a QCBox it is possible to simultaneously
measure frequency response and impedance of a loudspeaker; this tutorial will
guide you through the steps nedeed while setting up this test.
11.3.1 SETTING UP THE FREQUENCY RESPONSE
Open the sinusoidal menu. Let’s start with the acoustic frequency response; open
the settings dialog to set up the required sweep. The main parameters affecting
sweep are: frequency range, here chosen from 30Hz to 15kHz, resolution of 1/12 of
octave, supposed to be fine, and speed that is set to “Normal”.
Before taking the first measurement you still need to set the proper output level
(here chosen 1V at speaker terminals) as indicated by DUT specifications and
accordingly set input sensitivity of CLIO input A; as the final measurement will be
stereo operate separately the two input channel controls releasing the Link Input
Controls button in the hardware toolbar; initial input A sensitivity is -10dBV
(channel B is left to 0dBV).
Now choose CHA input channel selection and dBSPL as Y scale unit. Press go. The
first measurement gives you the following result
142 11 SINUSOIDAL