3.5 mm audio jack — TRS, TRRS, and connector rings explained
The 3.5 mm (⅛-inch) jack is the most common wired audio connector. The number of metal rings on the plug determines what signals it carries. Count the rings to identify the type.
Counting the rings
| Name | Rings (insulators) | Conductors | Use case |
|---|---|---|---|
| TS | 1 | 2 | Mono instrument cable (guitar, bass) |
| TRS | 2 | 3 | Stereo headphones, balanced mono |
| TRRS | 3 | 4 | Stereo headphones + microphone (headsets) |
| TRRRS | 4 | 5 | Balanced stereo (niche audiophile cables) |
What each segment carries (TRS)
| Segment | Carries |
|---|---|
| Tip (T) | Left audio channel |
| Ring (R) | Right audio channel |
| Sleeve (S) | Ground (common return) |
What each segment carries (TRRS)
Two wiring standards exist for TRRS. CTIA/AHJ is the dominant standard today (used by Apple, most Android).
| Segment | CTIA / AHJ (dominant) | OMTP (older, some Sony) |
|---|---|---|
| Tip (T) | Left audio | Left audio |
| Ring 1 (R) | Right audio | Right audio |
| Ring 2 (R) | Ground | Microphone |
| Sleeve (S) | Microphone | Ground |
If a headset microphone doesn't work on your phone or laptop, the device may expect CTIA while the headset is wired OMTP (or vice-versa). Passive CTIA-to-OMTP adapter cables are available for under $5.
TRS headphones vs TRRS headset
A headphone-only cable (no microphone) uses TRS. A headset cable (headphones + microphone) uses TRRS. Plugging a TRS cable into a TRRS jack works fine for audio. Plugging a TRRS headset into a TRS-only jack also works for audio, but the microphone will not function.
Balanced vs unbalanced audio
A standard 3.5 mm TRS headphone cable is unbalanced — one ground wire serves both channels, which can pick up noise over long cable runs.
Balanced 3.5 mm uses TRS differently: Tip = positive signal, Ring = negative (inverted) signal, Sleeve = shield. This is found on portable music players (some Sony Walkman, Astell&Kern) with balanced headphone outputs. A headphone wired for balanced 3.5 mm cannot be used unbalanced from the same plug.
3.5 mm vs 2.5 mm and 4.4 mm
Some audiophile players use 2.5 mm TRRS (Tip, Ring1, Ring2, Sleeve) or Pentaconn 4.4 mm for balanced connections. These are not compatible with each other or with standard 3.5 mm sockets without an adapter.