Mackie PPM1008 Owner's Manual - Page 25

Owner's Manual 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 polarity) side of the audio signal and pin 3 wired to the "low" ("cold" or negative polarity) side of the signal. See Figure A. This is all totally above board and in full accord with the hallowed standards dictated by the AES (Audio ­Engineering S­ ociety). 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. 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. • 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). SHIELD 2 HOT 1⁄4" TS Phone Plugs and Jacks COLD 3 1 SHIELD 1 COLD 3 2 HOT 1 3 2 SHIELD COLD HOT Figure A: XLR Connectors SLEEVE SLEEVE TIP 1⁄4" TRS Phone PTIP lugs andTIP Jacks "TRS" stands for Tip-Ring-Sleeve, the thSrLeEEeVE ­connections available on a "stereo" 1/4" or "­balanced" phone jack or plug. See Figure B. RING SLEEVE SLEEVE RING TIP TIP Figure B: 1⁄4" TRS Plugs RING TIP SLEEVE TRS jacks and plugs are used in several d­­ ifferent applications: • 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). • 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 to ground (earth). Mackie mixers do not directly accept 1-plug-type stereo micro­phones. "TS" stands for Tip-Sleeve, the two connections available on a "mono" 1⁄4" phone jack or plug. See Figure C. SLEEVE SLEEVE TIP TIP Figure C: TS Plug TIP SLEEVE TS jacks and plugs are used in many different ­applications, always unbRaINlGanSLcEeEVdE . ThSLeEEVtEipRINiGs cTIPonnected to the audio signal and the sleeve to ground (earth). Some TIP examples: RING • Unbalanced microphones TIP SLEEVE • Electric guitars and electronic instruments • Unbalanced line-level connections • Speaker connections Don't use guitar cords for speaker cables! They're not designed to handle speaker-level signals and could overheat. RCA Plugs and Jacks RCA-type plugs (also known as phono plugs) and jacks are often used in home s­ tereo and video equipment and in many other applications (Figure D). They are u­ nbalanced and electrically identical to a 1⁄4" TS phone plug or jack. Connect the signal to the center post and the ground (earth) or shield to the surrounding "basket." SLEEVE TIP SLEEVE TIP Figure D: RCA Plug Owner's Manual 25