RCA stands for Radio Corporation of America, the company that popularized this plug style. An RCA jack is a round, single-pin connector commonly used for home audio and video.

• Stereo audio: Typically two plugs—red for right, white (or black) for left.
• Composite video: Often yellow for standard-definition video.
• Other uses: The same style can carry digital coaxial audio or a powered subwoofer signal.

You’ll see RCA in cables, adapters, splitters, and panel-mount jacks. If you’re matching gear, pay attention to color-coding and whether you need male-to-male, female couplers, or 3.5mm-to-RCA adapters, which you can shop online or in store.

They look similar, but they’re not all built the same. Different uses call for different construction.

• Stereo analog: Two-channel left/right cables for receivers, amps, and players.
• Subwoofer/digital coax: Often 75‑ohm coax designs for longer runs and lower interference.
• Video (composite/component): Color-coded for legacy video gear.
• Build details: Shielding, connector fit, strain relief, and plating can vary. Gold plating can help resist corrosion but doesn’t guarantee better sound.
• Formats: Straight cables, Y‑splitters, couplers, and panel jacks cover different setups.

Choosing a cable that matches your application and run length can help reduce noise and maintain signal quality. You’ll find a range of options to fit simple and more demanding installs.

They both carry line‑level analog audio, but the connectors differ.

• AUX (3.5mm): A single TRS jack that carries stereo left/right on one plug—common on phones, tablets, and laptops.
• RCA: Two separate plugs (red/right and white/left) found on receivers, speakers, and older players.
• Connecting them: A 3.5mm‑to‑2‑RCA cable or adapter bridges the two formats.

When connecting portable devices to home audio, start with low volume and increase gradually to avoid overdriving inputs. Cable quality and length can influence noise pickup, so shorter, well‑shielded cables may help. Adapters and cables are available online and in stores.

RCA hasn’t disappeared—many setups still benefit from it.

• Home audio: Receivers, CD players, tape decks, and powered speakers.
• Turntables: Especially models with built‑in preamps or external phono stages.
• Subwoofers: LFE/mono inputs commonly use a single RCA run.
• Legacy video and retro gaming: Composite/component connections on older TVs and consoles.
• Car audio: Amplifier inputs often use RCA.

If your newer gear lacks analog ports, adapters or converters may help, depending on the equipment and signal type. Checking device manuals for supported connections can save time. You can shop a variety of RCA cables and adapters online or in store.

It’s possible, but consider a few trade‑offs.

• Simple splits: A Y‑splitter can feed two inputs (e.g., sending a subwoofer signal to L/R). This may slightly reduce signal level and can add noise with long runs.
• Input loading: Most modern inputs have high impedance, so basic splits often work for short, local connections.
• Better for distance or multiple zones: An active distribution amplifier can maintain level and isolation.
• Noise tips: Keep cables short, avoid running parallel to power cords, and use good shielding.

Y‑splitters, couplers, and longer RCA cables are widely available if you decide to try a passive split.