Turntable RCA Cable: Phono Level, Not Just RCA
Turntable outputs are special: tiny phono level signal, a grounding lead, and sensitivity to capacitance that other sources never think about.
Quick Answer
| Output | Signal | Goes to |
|---|---|---|
| Phono out | Tiny, RIAA equalised by the preamp | Phono input only |
| Line out | Built in preamp, standard level | Any line or aux input |
| USB out | Digital | Computers |
| Ground wire | Chassis earth | Phono preamp ground post |
Phono Versus Line
The level gap
Phono signals are millivolts and shaped by RIAA curves. Line inputs amplify them wrongly, thin and quiet.
The preamp
Either in the turntable, the receiver, or an external box. One, not two.
Switch position
Check the turntable’s line and phono switch matches the destination input.
Capacitance
MM cartridges care about cable capacitance. Keep runs short and decently specified.
The Ground Wire
- Connect the ground lead to the phono input’s ground post.
- Missing grounds produce a loud 50 or 60 Hz hum.
- One ground path only; doubled grounds can loop.
- Route signal cables away from power bricks.
- If hum persists, check the preamp and grounding order.
Real-World Applications
- Vinyl setups on modern receivers.
- Digitising records via interface.
- Retro hifi restorations.
- DJ booth patching.
Related Guides
For the RCA family, read audio cable RCA. For RCA plugs, see RCA plugs. For subwoofer runs, start with subwoofer cables.
FAQ
Can I plug phono into aux?
No. Level and equalisation mismatch make it thin and quiet.
Why the extra ground wire?
Hum rejection; the turntable chassis needs a single earth path.
Does cable quality matter here?
Capacitance affects MM cartridges; keep it short and specified.
Can I use a longer cable?
A little, with a line level output. Phono level wants short runs.