Bow:

A single channel audio recording.

Stereo:

A two-channel recording.

Dolby Axon:

Axon will make it possible in the future to transmit speech in video games in 3D. This makes it possible to see from which direction another player is coming or speaking to you. Distance, obstacles and other factors should be taken into account. Through Dolby Axon and the Voice Font it is also possible to change or completely manipulate voices. Dolby Axon uses a bandwidth of 16Kbit/s and can let up to 7.000 players communicate with each other. At the GDC, the technology was presented using the game Jumpgate Evolution, which will be released for PC. It could also be used on consoles.

Dolby Surround Pro Logic:

This multi-channel format can also be played on regular stereo equipment. In addition to the right and left, there is also a surroundChannel, which is limited from 100 Hz to 7 kHz and in mono on the rear Loudspeakers is given. Since the surroundSignal from the two stereochannels is extracted, the surround effect is weak. Many TV movies are broadcast in this format, which has been around since 1987.
Dolby Prologic requires rear speakers that cannot be located. You can point them against the back wall to get additional reflections. They transmit a narrow frequency band and both are fed with the same signal. So it's not a problem to use "humble" things.
The Dolby Digital or discrete 5.1, 5 equivalent channels are available. This means that ALL 5 channels are equipped with the same loudspeakers. Only in an emergency, when there is an extreme lack of space, is a smaller version of the same loudspeaker used. In the studio, for example, 3x Genelec 1032, 2x 1030.

Dolby Surround Pro Logic II:

Here, the rear channels are without frequency restrictions. The bass reproduction on the Subwoofer is improved. The surround channels are stereo. This format has been around since 2000.

Dolby Surround Pro Logic IIx:

With Dolby Pro Logic IIx you can convert stereo or 5.1 signals into 6.1 or 7.1.
There are different modes: Movie/Music with parameters like Dolby Panorama, Dolby Dimension, Dolby Center as well as a special game mode.

Dolby Surround Pro Logic IIz:

To use Pro Logic IIz, you need two additional Loudspeakers add to a previous 5.1 or 7.1 setup (9.1 system). The new boxes are located above the right and left front speakers, just below the blanket, which is why they are also called "height speakers".

With Pro Logic IIz, the source can be stereo or 5.1 material. The new system also works with existing 7.1 speaker configurations, so after the upgrade you end up with 10 speakers (7 main speakers, 2 height speakers and a subwoofer) in the living room.

Logic 7:

A system developed by Harman/Lexicon for the effective surround display of stereo or Dolby Pro Logic material.

AC-3:

The analogue Dolby Surround supplies the two rear surround boxes with the same sound effects. The digital AC 3 signal, on the other hand, contains for each Loudspeakers of surround system own information that the AC 3-Decoder via six discrete channels. Result: More elaborate effects, like a shot blasting across the room. In addition, the digitally delivered Ton a higher sound quality. Dolby Digital signals are currently only provided by DVDs and Laserdiscs.

DolbyDigital:

This sound format is available in different variants: 1.0, 2.0, ..., 5.1. The digit after the dot indicates whether there is a channel for the subwoofer (0 = none, 1 = there is a channel). 1.0 means mono, 2.0 means stereo, 5.1 means left (left), middle (center), right (right), back left (surround left), back right (surround right), subwoofer.
Abbreviated channel designations: L, C, R, SL, SR, LFE.
The sampling frequency is 48 kHz with a maximum of 24 bits. The bitrate varies from 64 kbps up to 448 kbps. 384 kbps is the normal rate for 5.1 and 192 kbps for stereo.
Lossy compression compresses by a factor of 12.
The subwoofer channel, if present, goes from 3 to 120 Hertz, whereby the 3 Hz is an optional requirement, ie not everyone will stick to it. This format has been around since 1992.

Dolby Digital EX:

This is the home version of Dolby Digital Surround EX
Here, Dolby Digital 5.1 is supplemented by a third surround channel, the rear center.
This format has been around since May 1999.

Dolby Digital Live:

Dolby Digital Live is a real-time coding technology that converts any multi-channel audio signal into a Dolby Digital data stream. With their help, audio signals from the PC can be converted to Dolby Digital via a single digital connection.Receiver or complete home cinema systems. Cumbersome multiple connections and tangled cables are a thing of the past. A grip on the input selector on the AV receiver is enough to play back any PC sound material via the system.

Dolby Digital Plus is a powerful next-generation audio codec that sets new standards in digital sound quality. These include higher audio fidelity and an expanded number of channels, as well as technology that is specially designed for future broadcast and streaming offerings. Building on Dolby Digital technology, Dolby Digital Plus was specifically designed to meet the changing needs of audio and video services and new storage media.

Dolby Digital Pulse:

Dolby Pulse is a total system that includes a bitstream format and proprietary encoding and decoding solutions. Compatible with the Open Standard Audio Codec MPEG-4U AAC Leverages Dolby Pulse for new developments across platforms such as HDTV, mobile phones, portable players, PCs and online entertainment Dolby's experience in content delivery. It also offers an extended bit rate utilization with HE AAC.

With true Dolby metadata capability, Dolby Pulse enables a single 5.1 stream to handle multi-channel, stereo and mono signals with seamless switching. This eliminates the need for bandwidth-intensive simulcasting. Meanwhile, Dialnorm values ​​embedded in broadcast streams determine loudness while preserving dynamic range. This means that Dolby Pulse can provide metadata capabilities equivalent to the metadata capabilities of Dolby Digital and Dolby Digital Plus, providing consumers with an excellent experience and a highly efficient solution for broadcasters.

In a broadcast landscape that now includes IPTV, mobile and Internet, as well as terrestrial, cable and satellite TV, Dolby Pulse is an important addition to Dolby's audio solutions. The company's goal is to extend Dolby Pulse throughout the broadcast chain � to be implemented in hardware, OEM products and licensed encoding and decoding solutions. Dolby Pulse corresponds to new HDTV-Specifications set by major European industry bodies such as EICTA, French and Spanish HD Forums and NorDig.

 

Dolby Digital Surround EX:

This is the cinema version of Dolby Digital EX
Here, Dolby Digital 5.1 is supplemented by a third surround channel, the rear center (SRC).
This format has been around since May 1999.

Dolby-E:

This format is the format in which you can cut lossless or frame-accurate and in which no data is lost. On television and radio and in the production of films with DD, everyone in the world should actually be working with this format if the advertising from Dolby is to be believed. As the last step of the DD production Dolby E then into the actual format DD, dts, DVD A etc converted.

Dolby headphones:

Designates a technology that enables the listening impression of a 5.1 surround system via conventional stereo headphones.
The technology used corresponds to a virtual artificial head. The sound from each of the 5 sound channels is digitally distorted in such a way that the brain perceives it as coming from a certain direction, e.g. B. from one Loudspeakers behind the listening position. Contrary to previous solutions refers Dolby headphones also includes the acoustic structure of the imaginary space by simulating reverberation and adjusting the time delay of the individual, virtual sound sources.
Although humans can locate sounds with two ears from all 3 dimensions, audio engineering now uses up to 7 Loudspeakers for the representation of a spatial sound. Dolby Headphone reduces the technology back to 2 "loudspeakers" within the headphones, although so far only the listening impression of a 5.1 system has been achieved.

The Dolby Home Theater v3 is a technologically advanced suite that enables desktop PCs and laptops to conjure up a cinematic listening and viewing experience at home or on the go. Thanks to powerful and highly developed digital signal processing technologies, the Dolby Home Theater to listeners and viewers Connection experience music, films and games in lively surround sound from 2 to 6 speakers or headphones.

Dolby Volume:

Everyone knows the situation: The feature film goes into the commercial break and it is much louder than the feature film - a marketing tactic to make viewers more aware of the advertised products. But sudden explosions after long, quiet dialogues also make many viewers reach for the remote control. Dolby helps with these problems Dolby volume now remedy.

This sound format works on two levels: The "Volume Leveler" compares the current sound spectrum with the previous ones. Dolby uses techniques from the professional sector, such as an "auditory scene analysis". This technique recognizes which tones need to be boosted and which don't. For example, Dolby Volume doesn't turn up a falling piano chord louder.

The second level is the "Volume Modeler", which reacts to the fact that the human ear perceives highs and lows less well at low volumes. Old stereo amplifiers had the Loudness-Button. However, they ignored the actual volume and often distorted the original signal into mush.

The Volume Modeler relies on the knowledge of data compression, which was developed with the invention of MP3 or Dolby Digital showed that sound data that is below the hearing threshold is simply omitted there. The Volume Modeler does the exact opposite: it raises the volume of sound components whose volume is below the hearing threshold Klang full and rich in detail even at low volume.

Unlike previous volume control solutions, Dolby Volume has no audible artifacts or side effects. So e.g. For example, the volume of quiet background noise between dialogue scenes is not increased or decreased as is the case with conventional compression technologies.

In addition to AV receivers, complete home cinema systems and stereo systems, Dolby Volume can also be integrated into televisions. Dolby Volume works with any input signal, analogue or digital, on any service (cable, satellite, terrestrial and IPTV) and for any program source. The first AV receivers and complete home cinema sets will hit the market in 2008.

 

Dolby True HD:

Dolby True HD describes an audio codec specially developed for the growing HD market, which is specially designed for use on Blu-Ray-Disks was developed as an optional, lossless surround sound format. The codec supports up to eight channels (corresponds to 7.1) with 24-bit samples and a sampling rate of 96 kHz. If fewer than 8 channels are used, the sampling rate can be increased to 192 kHz. The maximum data transfer rate is 18 MB/s.

Loss-free because the digital data stream is bit-exact to 100% of the sound mixer's mix Mastering corresponds to the film.

It is based on MLP (lossless compression algorithm for digital sound recordings) and sees itself as its successor. The transmission takes place via HDMI In 1.3.

 

STD:

A format with the same channel layout as Dolby Digital, mostly 5.1.
DTS works with a constant bit rate of 64 to 1536 kbit/s, on which DVD with 384 or 448kbit/s, the sampling rates go from 48 to 192 kHz at up to 24 bits. With the DVD there is compression, lossy, with a factor of 4.

Many DVD players will have a dts symbol on the front panel at a cursory glance, but many of these do DVD-Player don't even have a DTS decoder. If you look closely, the text "Digital Out" is under the DTS. This means that you have a receiver/amplifier must use with dts decoder in order to enjoy dts.
The subwoofer channel goes from 20 to 80 Hz.
This format has been around since May 1993.

DTS IT:

With 5.1, an additional channel for "Surround Rear Center" is obtained from the other channels, so it's not a real 6.1 format.

DTS ES 6.1 Discrete:

Here the "Surround Rear Center" channel is saved as a separate channel, making it a true 6.1 system.

DTS ES 6.1 Compatible:

This is a designation of a device about the way it creates the 6th channel per matrix from the other channels without an official DTS license.

DTS ES 6.1 Matrix:

Similar to "DTS ES 6.1 Compatible“ this is a saver version of DTS ES 6.1 Discrete.

DTS 24/96:

A 24-bit, 96kHz multi-channel format with up to 6 channels, uncompressed unlike Dolby Digital.

DTS Neo6:

Similar process to Dolby Surround Prologic II. DTS Neo6 but should be better: Up to 7 channels: separate subwoofer channel in stereo, EffectRearCenter as well effects speaker with full frequency range.

DTS HD Master

DTS-HD Master stands for "Digital Theater Systems High-Definition" and describes a lossless audio codec specially developed for the growing HD market with data rates of up to 6 Mbits/s (as a comparison: DVD 768 - 1,536 Kbit/s), downward compatibility to DTS, an unlimited number of channels and a sampling rate of 192 kHz.

Loss-free because the digital data stream is bit-exactly 100% the same as the sound engineer's mix when mastering the film.

DTS-HD Master Audio reveals 18 MB/s HD-DVD and 24,5 MB/s on Blu-Ray discs. In addition, it enables the sound master of the cinema film to be reproduced exactly, which was not possible with the predecessor DTS due to the high bandwidth of the sound master. In addition, low data rates are supported so that additional soundtracks or audio commentary can be stored as extensions and added to the main audio core. This core audio track is DTS compatible; once the extension has been added, it can only be output as 7.1 directly from the HDMI output or downsampled to DTS compatible 5.1 channels in real time.

The sound can be output analogously via all common outputs, but one cable is required for each channel. With DTS-HD Master, digital signals can only be transmitted unchanged via HDMI 1.3. HDMI 1.0 and 1.2 can only support DTS HD in PCM pass on dissolved. Optical and coaxial SPDIF (interface specification for the transmission of digital audio signals) only has the option of downsampling to 5.1 channels and a maximum bit rate of 1509,25 KB/s.

 

Circle Surround II by SRS:

Comparable to Dolby Pro Logic II, the Circle Surround technology developed by the American company SRS Labs also offers the option of playing back stereo or analog Dolby Surround sources over 5.1 channels. Circle Surround II (CS II) is an advanced, even more powerful surround matrix decoding technology that generates up to 6.1 channels from mono, stereo, Dolby Surround and Circle Surround sources.

DVD Audio:

A multi-channel format with different bit rates (20 and 24 bit), sampling frequencies (48 kHz, 96 kHz, 192 kHz) and channels 2 to 8.

2+2+2:

The 2+2+2 multi-channel process is a recording and playback process developed by mdg, compatible with stereo and surround playback. While only two-dimensional reproduction is possible with stereo and surround reproduction, the 2+2+2 multi-channel method not only enables three-dimensional sound reproduction, but also offers "optimal listening positions" throughout the room.

For 2+2+2 multi-channel playback, please use the existing stereo speakers (front right and left) and the rear ones Loudspeakers (rear right and left). In addition, mount another pair of speakers directly above the two front stereo speakers.
For a three-dimensional rendering, connect to the upper left Loudspeakers the signal from the center speaker to and to the right upper channel connect the signal from the subwoofer.

DSD or SACD:

Has been around since March 1999.
The sound format (rather sound recording format) is called DSD (Direct Stream Digital), the medium on which this format is stored is the SACD. Technically, the SACD is a DVD.
DSD is a recording format in which from sample- value to sample value (at the speed of 2,8 million samples/second) a change of maximum one bit is saved. The precision with which it is sampled is 24 bits.

The sampling frequency of 2,8 MHz is not directly comparable with those of the other formats. There are 2.0 and 5.1 channels and multi-layer disks (hybrid), which also have a normal CD is playable. If an SACD player has a digital SPDIF output, then this is currently (as of May 2003) only active when playing CDs; it is switched off for SACDs. Addendum January 2004: now there are devices on the market where the digital data stream is transmitted via iLink (IEE1394 or Firewire called) can be transmitted from the player to a receiver/decoder.
The developers Sony and Philips have filed the Super Audio CD specification, which includes the conventional CD standard, in the so-called "Scarlet Book".

MPEG-1:

The term MPEG not only applies to sound formats but also to image formats.
For video: system for data-reduced coding with low picture quality. Used at CD-I and video CD. For audio: system for data-reduced coding of up to 2 channels.

MPEG-2:

For video: system for data-reduced coding with high picture quality. Used on DVD. For audio: system for data-reduced coding of up to 7.1 channels.
The Data rate with high-quality MPEG -2 playback for image and sound is around 50 MB/s. An MPEG-3 format was originally planned for encoding the high-quality HDTV signals, but this was never implemented.

THX:

THX is not a recording format but a playback definition. It is set by the THX company as the Loudspeakers etc. must be designed so that a certain playback quality is achieved. The focus here is on the playback of film sound. THX does not necessarily mean Hifi and vice versa. In order to be allowed to use a THX logo on an amplifier or loudspeaker combination, the THX standards must be met and these are also checked.

MP3:

MP3 is not a multi-channel format, but only a stereo format so far (Update: MP3 surround sound, please refer HiFi knowledge). This file format is intended for storing compressed music, leaving out what you wouldn't hear. Here comes the example with the alarm clock: when it's quiet, you can hear it ticking.

But as soon as the alarm clock rings, you can no longer hear the ticking, although of course it continues to tick. That's why you can omit the ticking from a recording because nobody with healthy human ears can hear it. The CD has a bit rate of approx. 1400 kBit/s (WAV file), with MP3 bit rates of 128 to 320 kBit/s are usual, whereby many listeners hear no difference to the CD at 320 kBit/s.

SPDIF:

This isn't a sound format, it's a specification for an interface. SPDIF stands for Sony Philips Digital InterFace and is a digital input or output for digital audio in electrical format.
General SPDIF data:
sampling frequency CD 44.1kHz (2.8224 Mbit/s), THAT 48kHz (3.072Mbps)
Bandwidth: 100kHz – 6Mhz
Signal Bitrate: 2.8Mhz (Fs=44.1kHz), 2Mhz (Fs==32kHz) and 3.1Mhz (Fs=48kHz)
Pins: Digital In, Digital Out, VCC +5V, Gnd
Max. Resolution: 20bit (24bit optional).