APPENDIX A: 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 hallowed 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.

SHIELD 2

HOT

COLD 3 1

SHIELD 1

COLD 3 2

HOT

1SHIELD

3COLD

plug is connected tip to left, ring to right and 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).

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Figure A: XLR Connectors

HOT

1⁄4" TS PHONE PLUGS AND JACKS

“TS” stands for Tip-Sleeve, the two connections available on a “mono” 1⁄4" phone jack or

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

RING SLEEVE

SLEEVE RING TIP

TIP

RING

TIP

SLEEVE

plug (Figure C). TS jacks and plugs are used in many different applications, always unbalanced. The tip is connected to the audio signal and the sleeve to ground (earth). Some examples:

•Unbalanced microphones•Electric guitars and electronic instruments•Unbalanced line-level connections

SLEEVE

SLEEVE

TIP

TIP

TIP

SLEEVE

Figure B: 1⁄4" TRS Plugs

Figure C: TS Plug

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