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APPENDIX B: CONNECTIONS
“XLR” CONNECTORS
Mackie mixers use 3-pin female “XLR”
connectors on all microphone inputs, with
pin 1 wired to the grounded (earthed) shield,
pin 2 wired to the “high” (”hot” or positive po-
larity) side of the audio signal and pin 3
wired to the “low” (“cold” or negative polar-
ity) side of the signal (Figure A). All totally
aboveboard and in full accord with the hal-
lowed standards dictated by the AES (Audio
Engineering Society).
Use a male “XLR”-type connector, usually
found on the nether end of what is called a
“mic cable,” to connect to a female XLR jack.
2
2
3
1
1
SHIELD
COLD
HOT
SHIELD
COLD
HOT
3
SHIELD
COLD
HOT
3
2
1
SLEEVE
TIP
SLEEVE
TIP
RING
RING
TIP
SLEEVE
RING
Figure B:
1
⁄
4
" TRS Plugs
Figure A: XLR Connectors
1
⁄
4
" TRS PHONE PLUGS AND JACKS
“TRS” stands for Tip-Ring-Sleeve, the three
connections available on a “stereo”
1
⁄
4
" or
“balanced” phone jack or plug. See Figure B.
TRS jacks and plugs are used in several
different applications:
• Stereo Headphones, and rarely, stereo
microphones and stereo line connections.
When wired for stereo, a
1
⁄
4
" TRS jack or
plug is connected tip to left, ring to right and
SLEEVE
TIP
TIP
SLEEVE
TIP
SLEEVE
Figure C: TS Plug
sleeve to ground (earth). Mackie mixers do
not directly accept 1-plug-type stereo
microphones. They must be separated into a
left cord and a right cord, which are plugged
into the two mic preamps.
You can cook up your own adapter for a
stereo microphone adapter. “Y” two cables
out of a female
1
⁄
4
" TRS jack to two male
XLR plugs, one for the Right signal and one
for the Left.
• Balanced mono circuits. When wired as a
balanced connector, a
1
⁄
4
" TRS jack or plug
is connected tip to signal high (hot), ring
to signal low (cold), and sleeve to ground
(earth).
• Unbalanced Send/Return circuits. When
wired as send/return “Y” connector, a
1
⁄
4
"
TRS jack or plug is connected tip to signal
send (output from mixer), ring to signal
return (input back into mixer), and sleeve
to ground (earth).
1
⁄
4
" TS PHONE PLUGS AND JACKS
“TS” stands for Tip-Sleeve, the two connec-
tions available on a “mono”
1
⁄
4
" phone jack or
plug (Figure C). TS jacks and plugs are used
in many different applications, always unbal-
anced. The tip is connected to the audio signal
and the sleeve to ground (earth). Some ex-
amples:
• Unbalanced microphones
• Electric guitars and electronic instruments
• Unbalanced line-level connections