Dolby vs DTS: Which is Better?
 by: Andrew Ghigo


Dolby Digital and DTS Digital Surround Sound - Identifying the main differences between these multi-channel sound formats

This Dolby vs DTS surround sound is a rather hotly debated issue. Many audiophiles and home theater enthusiasts argue that DTS surround sound formats can deliver higher quality audio in comparison to their corresponding Dolby formats, with improved dynamic range, better representation of subtle detail in audio content, and improved signal-to-noise ratio.

Partly, this reasoning arises because DTS surround sound is usually encoded at a higher data rate than Dolby Digital and its lineup of associated formats.

This is more than understandable. We are dealing with lossy compression techniques. A higher bit-rate for the same format should normally implies superior sound during playback, as less compression in the encoding process should result in a better representation of the original sound source.

In this Dolby vs DTS debate, DTS people argue that they are after 'sonic perfection, not space consumption' - hence the higher bit rate and lower compression.

Dolby would counteract that their codec is more efficient and therefore, it can run at a lower bit rate.

In other words, one cannot simply draw conclusion on sound quality based on raw bit rates and compression figures alone; it also depends on how well designed are the encoding and decoding algorithms. And this makes sense too, but then...

There are relatively big differences in raw bit rates and compression levels when comparing Dolby vs DTS sound formats, implying a too wide a difference in codec efficiency - about 3 times as much - in favor of Dolby. Is it possible that Dolby sound formats achieve this level of codec efficiency?

The truth is that when dealing with different sound formats, the whole equation starts to get extremely complicated; it is not that easy to define what makes better sound.

This Dolby vs DTS is a much debated issue, but in reality is it true that one is better than the other?

To understand why this Dolby vs DTS surround sound controversy, it is necessary to have an understanding of the main differences between these formats. In particular, there are significant differences in bit-rate and compression levels as applicable to Dolby Digital and DTS Digital Surround. There are also important differences in the way these formats are implemented in movie house applications and in home entertainment.

It is not the scope of this write-up to go into these details; for the relevant information on the differences between Dolby and DTS, please read the full article appearing on Practical Home Theater Guide at http://www.practical-home-theater-guide.com/dolby-vs-dts.html.

At the same time, it is important to realize that these same differences between these two formats have actually given rise to this Dolby vs DTS controversy.

So where does this Dolby vs DTS debate leads?

Sound quality is an extremely subjective issue and therefore it is not easy to define what constitutes better sound. Opinions vary when comparing Dolby vs DTS and range from 'DTS is better' to 'Dolby Digital and DTS Surround Sound are pretty much the same'.

..and what do we say about this Dolby vs DTS debate?

Both Dolby Digital and DTS Surround are capable of achieving similar results in delivering surround sound, even though the lower compression and higher bit-rate of DTS Digital Surround should theoretically yield apparent benefits in sound quality.

At the same time, one cannot ignore the fact that these two formats make use of different coding schemes and syntax to perceptually compress audio.

This means that efficiency in terms of data utilization between these two formats is different. Therefore, direct comparison of the respective Dolby and DTS sound formats based solely on their raw bit rates, cannot be taken as an objective measure of sound quality.

Thus, while it is objectively possible to compare the resultant sound quality for the same audio format encoded at different bit rates, say in a movie house application and in home entertainment, yet it is not so straightforward when dealing with different formats.

Rather, for identically sourced audio content, it would be much easier for the listener during Dolby vs DTS 'blind' listening tests to notice a change in sound quality when changing the playback equipment between different brands, than when changing from Dolby to DTS.

In other words, you need a thoroughly refined audio playback setup to bring out that subtle difference in sound quality between these two formats.

About The Author
(c) 2004/2007 http://www.practical-home-theater-guide.com. All rights reserved.

Author: Andrew Ghigo – A Telecoms/Electronics engineer by profession, with specialization in digital switching and telecoms fraud management systems; a keen home theater enthusiast, with a lifelong interest in home electronics and a devoted audiophile for the last 25-yrs.

Editor and publisher of Practical Home Theater Guide (http://www.practical-home-theater-guide.com) - a comprehensive home theater guide to home theater systems, product reviews and home theater design.

This article is an excerpt from a series of informative guides appearing under the Home Theater Sound section of the site at http://www.practical-home-theater-guide.com/surround-sound.html.