How Can I Transmit a Dolby Pro Logic Signal from My Smart TV to My Receiver?

Transmitting a Dolby Pro Logic signal from your smart TV to your receiver requires some careful setup and configuration. Understanding the available output settings on your TV and the support on your receiver is crucial to achieve a surround sound experience through Dolby Pro Logic. Here are the detailed steps to guide you through the process:

Select the Right Output Format

When configuring your smart TV, choose between Dolby Digital or Dolby Digital Plus as your audio output. Both formats can carry a compressed 5.1 surround sound signal. Your receiver can decode this into Dolby Pro Logic II if it supports it. If your receiver only supports direct Dolby Digital decoding, Dolby Pro Logic II may not be achieved.

Connect to Your Receiver

To transmit the audio signal, use an optical TOSLINK or HDMI cable. HDMI is highly recommended if both devices support it, as it provides higher-quality audio signals.

Check Your Receiver Settings

Ensure that your receiver is programmed to decode Dolby Digital signals. Some receivers might also have a Dolby Pro Logic mode, which you can enable to process the incoming audio signal appropriately.

Content Source

It's important to confirm that the content you're watching supports Dolby Digital. Many streaming services offer this option, but some content may only be in stereo format. Even if the content is only in stereo, your receiver and smart TV can still convert it to Dolby Pro Logic using the appropriate settings.

Limitations of Dolby Pro Logic II

Dolby Pro Logic II is a matrix decoding technology designed to create surround sound from stereo inputs. If you only select PCM or stereo output from your TV, you won't achieve a surround sound experience. If your receiver doesn’t support Dolby Digital or Pro Logic, you may only receive stereo sound.

Dolby Stereo and Matrix Decoding

Dolby surround formats like Dolby Digital surround (DD surround) don’t define a specific data stream; instead, they describe a matrixed coding inside the stereo signal. This means that whether you transmit the stereo signal via PCM or Dolby Digital, your AV receiver can utilize Pro Logic decoding mode to obtain the 4.0 channels.

If you choose PCM, you get the stereo signal, and then you can select Pro Logic decoding. If you choose Dolby Digital, but your content only contains stereo data, you can still use Pro Logic. However, if the Dolby Digital stream carries six discrete channels, matrixed Dolby Surround coding will not be possible, and Pro Logic decoding will not work.

Dolby Digital (DD) is similar to Dolby Digital with an additional eight discrete channels. This can vary depending on the content and the device emitting the signal.

Reproducing the 4.0 Channels

Once you have the 4.0 channels LCRS decoded by Pro Logic, you need to reproduce them. If you have an old 4.1 surround receiver, the LCRS signals go to the LCR channels, and the S signal is sent to all the surround channels (SL, SR, etc.). The .1 subwoofer signal can be obtained via low-pass filtering and mixing to a single signal. For a 5.1 or 7.1 receiver, the LCR signals go to the corresponding channels, and the S signal is sent to all the surround channels. The .1 subwoofer can be obtained the same way as with a 4.1 receiver.

Some AV receivers can virtualize a 4.0 signal from clean stereo, even if the stereo signal does not contain Dolby Surround content.

By following these steps, you should be able to enjoy a Dolby Pro Logic experience from your smart TV through your receiver, providing a more immersive audio experience for your favorite movies and TV shows.

Conclusion

By making the right choices in your smart TV and receiver settings, you can unlock the full potential of Dolby Pro Logic and achieve a superior surround sound experience. Always ensure that the content you're watching is encoded in Dolby Digital, and that your audio system is configured correctly to take full advantage of the available features.