LEFT SIDE
RIGHT SIDE
MONO 1/4” to RCA
GOOD TEST
top jack
WHY DOES THE RED S LIGHT UP?: Notice that for this test, we connect the unbalanced 1/4” plug to the TOP 1/4”
Jack. (This odd configuration is made necessary by the internal bussing of the CBT-375, which keeps the unbalanced
1/4” jack separate from the RCA, in order to facilitate a wider variety of tests.) In a “good test”, the green H and S
LEDs will illuminate to indicate good through-connections. You may ignore the red S LED, which lights because we’ve
used the balanced jack for the unbalanced 1/4” plug in this test only. But if the red H LED illuminates, that would indi-
cate that cable repair is needed, due to a “bridged” (short) condition in the cable.
LEFT SIDE
RIGHT SIDE
GOOD TEST for PIN 2 HOT
GOOD TEST for PIN 2 HOT
GOOD TEST for PIN 3 HOT
GOOD TEST for PIN 3 HOT
XLR (M) to TRS 1/4” (BALANCED)
TRS 1/4” (BALANCED) TO XLR (F)
Not all monufacturers of audio gear agree upon a standard for connecting 3-pin
XLR plugs to other kinds of plugs. Most manufacturers are specifying Pin 2 as the
“hot” pin and Pin 3 as the “cold” pin. The differences in good tests for Pin 2 Hot,
and Pin 3 Hot are shown at the right.
Exception: Use the top
1/4” Jack for this test.
