When it comes to setting up your home theater system, one of the important decisions you’ll need to make is whether to use Bitstream or PCM for your soundbar. PCM and Bitstream are two popular audio formats, each with its pros and cons.
Whether you’re a cinephile, a dedicated gamer, or just someone who appreciates crystal-clear sound, choosing the right audio format for your soundbar is very important.
In this blog post, we’ll shed some light on these audio output formats to ensure your audio needs are met and you make the most out of your money. We’ll discuss how these formats work, their advantages and disadvantages, and address some specific scenarios to help you choose which one is suited for your soundbar setup.
Quick Comparison: PCM vs. Bitstream
Here is the quick difference between these two popular audio formats:
What is PCM?
PCM stands for Pulse Code Modulation and is an audio format that converts analog audio into digital signals. The common applications of PCM are in radio, telecommunications applications, and home theater setups. It is something that has been around longer than Bitstream.
PCM requires a lot of bandwidth as there is no compression during the signal conversion. As a result, you’ll get high-quality audio from your soundbar.
• Uncompressed audio for exceptional clarity
• Compatible with most audio devices
• Limited channel support
What is Bitstream?
Bitstream, also called binary sequence, converts analog signals into digital signals. Bitstream breaks the audio signals into small parts, and this signal is relayed based on the format you choose. Various surround sound formats such as DTS:X, DTS-Master Audio, Dolby Atoms, Dolby Digital, and more use Bitstream. Home theater systems and a lot of disc players use this audio transmission technology.
• Suitable for 5.1 and 7.1 soundbars
• Supports advanced audio formats like Dolby Atoms
Bitstream or PCM for Soundbar: Comparison Table
Let’s dive deeper into the comparison between PCM and Bitstream, considering various aspects.
| Aspect | Bitstream | PCM |
| What is it? | Transforms analog output audio signals into digital bits and sends them to a receiver. | The process of quantizing an analog signal to binary values and sampling the signal regularly at a set rate results in an uncompressed digital representation of that signal. |
| Compatibility | Compatibility with modern surround sound players | CD, DVD, and Blu-ray players are all compatible |
| Optical / Coaxial | Up to 5.1 digital optical or coaxial outputs are supported | Support for digital optical or coaxial output is limited |
| Audio Output | High-quality audio output requires flexible transmission | Transmission requires more bandwidth to reduce quality degradation |
| Transmission | Compatible with players and receivers that only support digital sound | Compatible with analog and digital sound players and receivers |
| Secondary Audio | Limited options, but guaranteed secondary audio quality | High-resolution secondary audio channels better supported |
| Audio Processing | Audio sinks connected to the source (soundbars, preamps, AVRs, and DACs) process audio. | The source (TV, streaming box, Blu-ray, DVD, CD player, gaming console, etc.) handles audio processing. |
| Connection | HDMI, optical, and coaxial | HDMI, optical, and coaxial |
| Bandwidth | Needs limited bandwidth | Need a lot of bandwidth |
| Soundbar | 5.1 and 7.1 soundbars | Stereo and 2.1 soundbars |
In-Depth Comparison of Bitstream and PCM
Now, let’s dive in-depth to further explore these audio transmission methods.
Decoding
Bitstream sends audio in a compressed form that reduces bandwidth requirements. This compression may result in a loss of audio quality, especially in complex soundtracks.
PCM transmits data in uncompressed form, resulting in higher bandwidth requirements, but the audio quality is great. PCM decodes data before it goes to the receiver, while bitstream sends compressed data, which is then decoded in the receiver.
Audio File
PCM uses WAV or FLAC file formats that are widely supported and known for high-quality audio reproduction. Bitstream can handle various audio formats, including advanced ones such as Dolby Atoms, DTS:X, Dolby TrueHD, etc.
PCM deals with the conversion of both digital and analog signals, while Bitstream is only for digital transmission. The PCM audio files are larger due to a lack of compression, while the bitstream files are smaller due to compression.
Audio Output
As PCM doesn’t involve any compression, it requires more bandwidth for audio transmission. Due to higher bandwidth, quality degradation is minimized and performance is improved. As a result, you’ll get exceptional audio clarity and the highest-quality sound.
Bitstream audio is compressed, so it requires less bandwidth for audio transmission. Bitstream also provides good audio quality but may not match the clarity of PCM. It, however, offers more flexibility for receivers and speakers to provide a higher-quality audio output.
Compatibility
PCM is compatible with a wide range of devices, including Blu-ray, DVD, and CD players. It works seamlessly with most audio devices and soundbars.
Bitstream compatibility varies and is often better suited for newer players and soundbars that support surround sound formats.
Connection
PCM only uses wired connections to transfer audio streams, while Bitstream can be transferred through wired and wireless connections. Both can work easily with HDMI, optical, and coaxial connections.
Optical/Coaxial
While PCM supports a limited number of digital coaxial output options, Bitstream is more flexible and can support digital coaxial and optical output up to 5.1 systems.
Secondary Audio
There may be limited support for secondary audio with PCM, depending on the device and the source. It depends on the source and soundbar technology to determine whether Bitstream supports secondary audio.
PCM offers higher performance since it supports secondary audio channels with high resolution. There are good secondary audio options in Bitstream, but they aren’t as versatile as PCM.
Soundbar
As most modern soundbars support both PCM and Bitstream audio formats, the choice usually comes down to your source.
In stereo and 2.1 soundbars, where audio quality is paramount, PCM is the ideal choice.
If you have 5.1 and 7.1 soundbars that support advanced audio formats, such as Dolby Atmos, Bitstream performs very well.
Transmission
PCM offers standard data transmission, which means it transmits audio in an uncompressed form, requiring more bandwidth but preserving audio fidelity.
Bitstream compresses audio data, requiring less bandwidth but potentially sacrificing some audio quality.
While Bitstream only works with receivers and players that support digital sound transmission, PCM can work with both digital and analog receivers and players. A bitstream transmits bits at regular intervals without any start or stop signals.
When to Use Bitstream?
Those who have a soundbar that supports Dolby Atmos should opt for Bitstream for the best experience. In streaming situations where bandwidth matters, Bitstream is more efficient.
A receiver with better processing power or a sound system relying on the receiver can use Bitstream. When you have a 5.1 or 7.1 soundbar, choose Bitstream, especially if it supports advanced audio formats like Dolby Atmos.
While Bitstream can be used for secondary audio, the output can be limited. You won’t hear an improvement in sound quality if you don’t have a high-end receiver.
Investing in a high-end receiver, therefore, will make a noticeable difference. The immersive audio experience can enhance gameplay when Bitstream is used for gaming.
When to use PCM?
The PCM configuration has concrete reasons for being preferred over Bitstream, even though both work to improve audio quality. For instance, PCM configuration is an excellent option if you want a direct and fast connection with reduced output latency. PCM can even be used for high-quality secondary audio.
For stereo and 2.1 soundbars, PCM is the best choice. Whenever you have multiple audio sources, use PCM, as it is compatible with many audio formats.
PCM may be your best option if you prioritize audio quality above all else and have a high-quality sound system. If you’re not sure if your devices are compatible, PCM is a safe bet.
If your sound system can only play the audio files from the player, you can choose PCM. Additionally, if you want to prevent the receiver from converting audio files, you can change the configuration.
When you have a sophisticated sound system, PCM may fail to deliver a smooth transmission. The PCM format is the way to go if you’re an audiophile who values uncompromised audio quality.
Bitstream or PCM for Specific Scenarios and Soundbar Models
1. For Dolby Atmos
Bitstream is the preferred format for Dolby Atmos content. Adding Dolby Atmos to a home theater can create an immersive audio experience that is captivating for viewers.
2. For Samsung Soundbar
On many Samsung soundbars, both bitstream and PCM formats are supported. You should make your choice based on the soundbar model and your preferences for audio. It may be better to use Bitstream if you have a newer Samsung soundbar that supports Dolby Atmos.
3. For Soundbar for Gaming
Gamers can benefit from Bitstream, especially if their soundbars and gaming consoles support advanced audio formats. This can enhance the gaming experience and make it more immersive.
4. For 2.1 Soundbar
With PCM, you can enjoy the best audio quality for stereo setups with 2.1 soundbars. Whether you’re watching a movie or listening to music, it’s perfect.
5. For 5.1 Soundbar
The Bitstream codec is better suited for 5.1 soundbars since it can handle surround sound and advanced audio formats more efficiently.
6. For LG Soundbar
Soundbars from LG are compatible with both Bitstream and PCM formats. To make the best decision, take into account your specific LG soundbar model and the content you plan to watch.
7. For Bose Soundbar
Bose soundbars are known for their high-quality audio. Bose soundbars can benefit from PCM, ensuring you get the most out of their high-quality audio.
8. For Vizio Soundbar
Soundbars from Vizio support both PCM and Bitstream. Depending on the Vizio soundbar model you own and your audio preferences, you will be able to make the best decision for yourself.
Frequently Asked Questions (FAQs)
Should I use PCM or Bitstream on my soundbar?
PCM and bitstream depend on your audio setup and preferences. Consider these factors when making your decision:
- Use PCM when:
- Audio quality is of utmost importance to you.
- You’re unsure of the compatibility of your devices, as PCM is widely supported.
- Uncompressed audio is what you want.
- Use Bitstream when:
- Your soundbar supports advanced audio formats like Dolby Atmos, which Bitstream can transmit.
- You need efficient data transmission, especially for streaming.
- The source and soundbar you use are compatible with Bitstream.
What is PCM vs. Bitstream for HDMI ARC?
Both PCM and Bitstream can be used with HDMI ARC (Audio Return Channel). ARC allows your TV to send audio to a soundbar or receiver. Here’s how they differ:
- PCM for HDMI ARC: Your TV sends audio in its original form to your soundbar. This option is straightforward and widely supported.
- Bitstream for HDMI ARC: Here, your TV transmits a compressed audio signal to your soundbar, which decodes it. If you have advanced audio formats like Dolby Atmos, Bitstream can handle them.
You can choose between them depending on your audio source and soundbar capabilities.
Why does PCM sound better than Bitstream?
Because PCM preserves audio in its raw, uncompressed form, it often sounds better than Bitstream. This ensures high fidelity by retaining every detail of the original audio. A bitstream, on the other hand, is compressed, which can result in a slight loss of audio quality. Many users may not notice the difference in sound quality, especially when using high-quality equipment.
Can PCM carry Dolby Atmos?
Dolby Atmos audio can be carried over PCM, but with a caveat. It is true that Dolby Atmos incorporates object-based audio, which is transmitted via PCM if the source device and soundbar support it. It is more common to transmit Dolby Atmos through Bitstream, which is optimized for advanced audio formats. Despite PCM’s ability to carry Dolby Atmos, Bitstream is often the preferred choice, especially when paired with compatible soundbars.
Final Words
Choosing between bitstream and PCM for your soundbar can have a significant impact on the quality of your audio. To make the right choice, consider your audio source, your soundbar’s capabilities, and your audio preferences.
There’s a format for everyone, whether you’re looking for efficiency, compatibility, or audio quality. You should experiment to determine which one offers the best sound quality for your home entertainment system.