Adjustment of the volume controller:
With a nominal impedance of the connected speaker box of 8 ohm, the Speaker Checker emits 1 W
output power when the volume controller is in position (10). When testing a 4 ohm speaker box, you
should adjust the level lower, since otherwise the output signal distorts. With 4 ohm load, there is a
reference position of the volume controller of 2 to 3 o’clock.
Output jacks
(rear side) :
Speakon output jack:
Assignment: The signal is output to all 4 poles of the jack
PIN 1+ and 2+= Signal (+)
PIN 1- and 2- = Signal (-)
XLR output jack:
Assignment (switch position asymmetrical):
PIN 1 = Signal (-)
PIN 2 = Signal (+)
PIN 3 = not connected
Assignment (switch position symmetrical):
PIN 1 = Ground
PIN 2 = Signal (+)
PIN 3 = Signal (-)
Important:
The 1 W power amplifier of the Speaker Checker is designed as bridged power amplifier. This means
that both speaker lines conduct a signal which is phase-shifted by 180°. So there is no reference
ground required for a speaker test. When the XLR-output is set to symmetric operation, PIN 1 is the
point of reference; the signals are present at PIN 2 and 3.
Checking a loudspeaker box:
Connect the Speaker Checker and the loudspeaker box to be checked with a loudspeaker cable. If
you are using the XLR output jack, set the selector switch of the XLR output to asymmetric operation.
If you are using a Speakon loudspeaker cable, the position of the switch is unimportant. Switch on
the Speaker Checker and turn the volume controller in clockwise direction until a clear tone can be
heard. Now you can check all loudspeakers (bass, middle and treble speakers) of the loudspeaker
box by means of the frequency setting.
Checking of a single, dismantled loudspeaker:
For doing so make a testing cable which has open, soldered cable ends or crocodile clips at one end,
and the plug (Speakon or XLR) for connection to the speaker at the other side. With this adapter
cable you can connect any loudspeaker and check it for function.
