Jacks and Plugs

TIL that beyond simply “TRRS” 3.5mm jacks, that carry a microphone signal in addition to left/right audio for headphones (etc), there are two standards, CTIA and OMTP.

Pretty much everything I use seems to be CTIA:

• SoundBlaster Play! 4 specs: “1 x ⅛″ Headphone-out Jack (4-pole, CTIA)”
• HyperX Cloud Stinger headset
• Apple (though theirs is somewhat nonstandard in that it apparently “uses a non-standard microphone and control signaling method”)
• Sennheiser PC38X (discussion)
  

Next, common power plugs we use every day have names and specifications (duh). I’m cobbling together a poor man’s iMac (a Mac Mini mounted to the back of a matte monitor), and one of the things I want to ensure is that there’s a single power cord required, just like an iMac.

The three prong “computer” power plug? The “male” version is an IEC 60320 C14 (a/k/a the IEC 320 C14) connector, the “female” part the C13. The part that plugs into a North American 110V outlet? NEMA 5-15P (“125V, Class 1, 15A plug”). (The female version is the NEMA 5-15R; 125V, Class 1, 15A receptacle.)

The two prong “infinity” plug used by many electronic devices (including the Mac Mini)? IEC 60320 C7. (The polarized one with the squared off end? Related, but not part of the standard.)

Then there’s this nifty adapter (C14 male to accept a long NEMA 5-15P to IEC-320-C13 power cord, splitting to a C13 female (for the monitor) and C7 female (for the Mac mini), which let me do a one-cord arrangement with my “duct tape iMac” project ...

IEC-320-C14 (right) to NEMA 5-15R

NEMA 5-15P (left) to IEC-320-C13