Quick answer: An av to hdmi port needs an active converter, because composite or component video is analog and HDMI is digital. A passive cable with RCA plugs on one end and an HDMI plug on the other will not produce a picture. The converter digitizes the analog signal, scales it to 720p or 1080p, and embeds the red and white audio into the HDMI stream. It needs its own power and works in one direction only.
The television is fine, the old console or camcorder is fine, and the cables between them are fine. The problem is that one end of the chain speaks in three RCA plugs while the other end listens only on HDMI, and every input on the set is digital. Work out which analog format you actually have before ordering a box, because the converter and the result both change with it.
Which analog format is on the back of the device
Composite: yellow, red, white
One video plug carries brightness and both colour components together, at 480i or 576i. It is the lowest quality link in common use and still the most common on older game consoles and camcorders, which is why edges look soft and reds bleed on a modern panel.
Component: green, blue, red
Three video plugs carry luma and two colour difference channels. Component can pass 480p, 720p, and 1080i, and a converter fed from it usually looks noticeably cleaner than one fed from composite, because the source has already separated the colour information.
S-Video and SCART
S-Video splits luma and chroma into a four pin mini DIN plug and beats composite on the same source. SCART is a European multi pin connector that may carry composite, RGB, or both, so check the device manual rather than assuming what the socket provides.
Why a passive adapter cable cannot work
Analog video is a continuously varying voltage. HDMI is a stream of digital packets over four high speed pairs. Moving between them requires sampling, timing recovery, and encoding, which needs active electronics. A lead that simply joins an RCA plug to an HDMI plug contains nothing capable of that work, whatever the listing title suggests. Any product that functions has a box, a chip, and a power input.
What the converter has to do well
Scaling comes first: the source is usually 480i and no HDMI input will accept that, so the box must output 720p or 1080p. Deinterlacing comes next, since 480i delivers half a frame at a time and a weak scaler shows comb teeth on any moving edge. Audio must be sampled from the red and white plugs and embedded into the HDMI stream, or you get a picture with silence. Aspect ratio handling matters too: a 4:3 source on a 16:9 panel needs pillarboxing, and cheaper units stretch it without asking.
One direction, one input, one output
These converters are almost always analog in, HDMI out. Feeding HDMI into the RCA side does nothing at all. Boxes advertised as working both ways usually mean a switch between two separate circuits, not a true bidirectional converter, and the reverse direction is a different product with different limits. Budget for a power outlet near the converter as well, since the USB lead is short on most units.
| Source format | Plugs | Typical signal | Converter output | Watch for |
|---|
| Composite | 3 RCA | 480i or 576i | 720p over HDMI | Soft edges, combing, 4:3 stretch |
| Component | 3 RCA, marked Y Pb Pr | Up to 1080i | 1080p over HDMI | Colour space mismatch, green tint |
| S-Video | 4 pin mini DIN | 480i | 720p over HDMI | Fewer boxes still offer this input |
| SCART with RGB | 21 pin | 576i | 720p or 1080p | Confirm the socket outputs RGB |
Practical scenarios
- Old game console on a new TV: composite into a converter set to 720p is the cheap route, but expect lag of a few frames, which matters in fast games.
- DVD player and a soundbar: send video to the TV by HDMI and check whether the converter passes audio through, otherwise run the red and white plugs to the soundbar directly.
- Camcorder playback for family: an S-Video or component feed gives a cleaner archive copy than composite, and the converter output can go straight into a capture device.
- Receiver with no analog inputs left: a converter box in front of an HDMI input works, but use a switch if several old devices need the same port.
FAQ
Can I just use an RCA to HDMI cable?
No. A cable with no electronics cannot digitize an analog signal. If a product works without a power source, it is either mislabelled or it is not doing a real conversion.
Will the picture look as good as the original?
It will look different. A good converter preserves the source faithfully, but 480i scaled to 1080p is still low resolution content, and no box invents detail that was never recorded.
Does the converter affect HDMI copy protection?
Analog inputs do not carry HDMI copy protection, so the converter simply digitizes what it receives. The HDMI output still has to satisfy whatever the display expects, which is why cheap boxes occasionally show a blank screen on some sets.
Next step
Get the analog source onto HDMI first, then plan the rest of the chain. Our comparison of a splitter versus a switch helps when several devices compete for one port, the ARC cable guide covers sending sound back to a receiver, and ARC versus eARC explains which audio formats survive the trip.
