Thru Output; Level Knob / Ol Led - Mackie Thump 12 Owner's Manual

Thump12 / Thump15 Loudspeakers: Rear Panel Features continued...
7 8
To connect a balanced line to this input, use a
1/4" Tip-Ring-Sleeve (TRS) plug. "TRS" stands for
Tip-Ring-Sleeve, the three connection points
available on a stereo 1/4" or balanced phone jack
or plug. TRS jacks and plugs are used for balanced
signals and stereo headphones and are wired as follows
according to standards specified by the AES (Audio
Engineering Society):
Balanced 1/4" TRS Connector
Sleeve – Shield (ground)
Tip – Positive (+ or hot)
Ring – Negative (– or cold)
Balanced 1/4" TRS Connector
To connect an unbalanced line to this input, use a
1/4" mono (TS) phone plug, wired as follows according
to standards specified by the AES (Audio Engineering
Society):
Unbalanced 1/4" TS Connector
Sleeve – Shield (ground)
Tip – Positive (+ or hot)
Unbalanced 1/4" TS Connector
For more information on these connectors, see
Appendix B on page 14.
10
Thump12 • Thump15 Powered Loudspeakers
9 10 6
5 4
11
RING SLEEVE SLEEVE RING TIP
TIP
RING
TIP
SLEEVE
SLEEVE SLEEVE TIP
TIP
TIP
SLEEVE

5. Thru Output

This is a male XLR-type connector that produces
exactly the same signal that is connected to the input
jack. Use it to daisy-chain several Thump loudspeakers
together off the same signal source(s).
They are wired as follows, according to standards
specified by the AES (Audio Engineering Society):
Balanced XLR Output Connector
Pin 1 – Shield (ground)
Pin 2 – Positive (+ or hot)
Pin 3 – Negative (– or cold)
Balanced XLR Output Connector
See page 7 to learn more about daisy-chaining Thump
loudspeakers.
For more information on these connectors, see
Appendix B on page 14.

6. Level Knob / OL LED

The level knob adjusts the overall signal level at the
input to the built-in power amplifiers. It ranges from Off
(– ) to MAX (maximum gain), with unity gain at the
center position (12 o'clock).
• Thump loudspeakers are designed to operate with a
+4 dBu signal when the level knob is at the U (center)
position.
• Thump loudspeakers may accept up to a +20 dBu
signal by turning down the level knob accordingly.
Turning the level knob past unity will provide enough
gain to connect a microphone directly.
NEVER connect the output of an amplifier
directly to the input of the loudspeaker.
This could damage the input circuitry
of the active loudspeaker.
The accompanying OL (overload) indicator
illuminates red when the amplifier in the Thump
loudspeaker is near the clipping point. It is OK if
the OL LED blinks occasionally, because this means
that the transient peaks are just reaching the maximum
output of the amplifier and you are getting the most
out of the loudspeaker.
SHIELD 1
3
2
COLD
HOT
SHIELD
1
3 COLD
2
HOT