PCM VS. BITSTREAM: WHICH AUDIO SETTING IS BETTER?
You have connected your Playstation or another device to the AV receiver and are now faced with the choice between “Linear PCM” and “DTS (Bitstream)”? In this article, we’ll help you make the right
TABLE OF CONTENTS
PCM and LPCM
PCM, or pulse code modulation, is a general term for digital audio formats in which the audio signal is divided into individual samples. If you select PCM, the Playstation decodes the audio material in advance and passes it on to the next device (possibly an AV receiver). This means that the signal is passed on “as is” from the receiver to the connected speakers.
LPCM (Linear Pulse Code Modulation) is a special uncompressed PCM format in which the samples are encoded linearly. This means that the gradations between the value ranges are the same. Also, LPCM works without data compression and reduction. In this way, a loss-free transmission and an exact image of the original signal is reconstructed. The sampled values are used directly, without prior decoding or conversion of the signal. Linear PCM is particularly important in high-quality audio applications, as it results in precise and unadulterated audio reproduction.
Bitstream
Bitstream
Bitstream, also known as data stream, is an alternative method of digitizing audio signals. Bitstream uses variable bit rates and is often combined with compression algorithms such as Dolby Digital or DTS. If you select Bitstream, your Playstation forwards the unprocessed audio signal (e.g. in Dolby Digital, Dolby Atmos, DTS or DTS:X containers) to the AV receiver. This means that the AV receiver has to decode the audio signal. However, the receiver must also support the codec supplied by the Playstation.
Bitstream is often used in surround sound systems, home theaters and when transmitting audio signals over limited channels. This method is also widely used for streaming services and digital radio broadcasts.
Dolby und DTS
Dolby and DTS are well-known companies that specialize in the development of audio compression and coding technologies. Dolby Digital and DTS are widely used bitstream formats that are used in home theater systems and cinemas to provide surround sound.
Advantages and disadvantages
Ultimately, it depends on your requirements and your AV receiver which type of decoding is the right one for your system. Let’s first take a look at the advantages and disadvantages of PCM and bitstream.
PCM
Advantages:
- High sound quality thanks to an uncompressed signal: PCM offers accurate and precise capture of audio signals, resulting in outstanding sound quality. All details of the original audio are retained. This makes PCM particularly interesting for audiophile users and professional users in music production for mixing and mastering.
- PCM audio can be played directly from any device that supports digital audio as no decoding is required.
Disadvantages:
- Larger file sizes: Uncompressed PCM can result in large files, which requires storage space and bandwidth.
Bitstream
Advantages:
- Efficiency: Bitstream can reduce file sizes and is well suited for transmission over limited channels.
Disadvantages
- Compression: Compression can lead to a loss of quality. However, this is barely perceptible to the average human listener.
- Dependence on other devices in the chain: Your AV receiver must support the output of your Playstation in this case. You can often quickly tell whether your receiver supports Dolby Atmos, for example, by the corresponding logo stickers on your receiver.
Tip:
If you have an older AV receiver that is not able to decode an uncompressed bitstream (Dolby Digital, Dolby Atmos, DTS or DTS:X etc.), your Playstation can convert it into an uncompressed (L)PCM stream. This is also compatible with older devices.
Conclusion
There is no single solution that is suitable for all applications. PCM offers uncompressed sound quality and precision, while bitstream improves efficiency and transmission capabilities. Both technologies have their areas of application as well as advantages and disadvantages. When choosing between PCM and bitstream, it is crucial to consider the specific requirements and the intended use. If your Playstation is connected to a TV, the PCM setting may make more sense. If your AV receiver supports different bitstream containers, the bitstream setting is more suitable.
If you notice a delay in the audio playback when gaming, it may be worth switching to PCM and checking whether the delay in the audio signal disappears.