Pinouts, the ones we keep on the wall

For the bench

The wirings we reach for most, drawn the way you read the connector: looking into the socket for XLR, speakON and DIN, side-on for jacks and RCA. Every one is a published standard — where a wiring is not standardised, it says so.

1 3 2

XLR, balanced

IEC 61938 / AES14

1
Shield, chassis ground
2
Hot, signal in phase (+)
3
Cold, signal out of phase (−)
All connectors →
T R S

Jack, balanced (TRS)

IEC 60603-11

Tip
Hot (+)
Ring
Cold (−)
Sleeve
Shield

Same plug as a stereo jack, wired differently. A balanced TRS into a stereo input gives you one channel out of phase, not two channels.

T R S

Jack, stereo (TRS)

IEC 60603-11

Tip
Left
Ring
Right
Sleeve
Common return
T S

Jack, unbalanced (TS)

IEC 60603-11

Tip
Signal
Sleeve
Shield and return
T R1 R2 S

Jack, headset (TRRS)

CTIA / AHJ wiring

Tip
Left
Ring 1
Right
Ring 2
Ground
Sleeve
Microphone

Two incompatible wirings exist. CTIA (above) is what phones use. The older OMTP swaps ground and microphone — a headset wired one way into a socket expecting the other still passes audio but loses the mic.

1+ 2+ 1− 2−

speakON, 4-pole

Neutrik NL4 pin naming

1+
Amplifier channel A, positive
1−
Amplifier channel A, negative
2+
Amplifier channel B, positive
2−
Amplifier channel B, negative

A two-conductor cable uses 1+ and 1− only. Bi-amped and bridged cabinets use 2+ / 2− as well, so check the cabinet before assuming a 4-core is wired through.

All connectors →
Centre Shell

RCA, unbalanced

IEC 60603-14

Centre pin
Signal
Outer shell
Shield and return
1 2 3 4 5

DIN 5-pin, MIDI

MIDI 1.0 electrical spec

1
Not connected
2
Shield, at the source end only
3
Not connected
4
Current source
5
Current sink

Pins 1 and 3 are unused in classic MIDI. Some equipment carries phantom power on them — do not assume they are dead.

N E L

Mains inlet, 3-pin

EU harmonised colour code

L
Live — brown
N
Neutral — blue
E
Earth — green and yellow

Mains wiring is not a DIY exercise if you are unsure. Colours here are the EU harmonised code; older and non-EU equipment uses others.

Standards move and manufacturers deviate. If a cable matters, ring it out with a meter before you trust a chart — ours included.