DVD-Audio

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DVD-Audio logo

The DVD-Audio is a DVD variant mainly for playing music in surround sound 5.1 is used. It was considered a successor to the audio CD ( compact disc ).

Structure of DVD-Audio

DVD-A and DVD-V are visually indistinguishable (from below).
DVD-Audios are offered in a special super jewel case .

A DVD-Audio is a DVD-ROM that contains files with a specified structure (AOB files) in a special subdirectory (AUDIO_TS) and can be played on a DVD-Audio player. In addition to losslessly compressed audio signals, these files also contain still images.

Differences from DVD-Video

property
Video logo
Audio logo
Publishing year 1996 2000
Resolutions (bit) 16, 20, 24 16, 20, 24
Sampling frequencies (kHz) 48; 96 44.1; 48; 88.2; 96; 176.4; 192
Maximum discrete channels theoretical 8 (LPCM)
factual 7 (DTS-ES) 		6th
Sound formats LPCM (lossless), MPEG-Audio , Dolby Digital , DTS LPCM , MLP
Audio, not compressed Yes (LPCM) Yes (LPCM)
Audio, compressed without loss No Yes (MLP)
Audio, lossy compressed Yes ( MPEG-Audio , Dolby Digital , DTS ) No
Audio data rate (Mbit / s) 6,144 (62%) 9.8 (100%)
Stereo downmix ■ □ □ ■ ■ ■ ( SMART )
Moving images Yes No
Still image gallery
(per title, for lyrics etc.) 		Yes, as a video (less efficient) Yes, directly as still images
subtitle Graphic overlays Coded
Regional codes Yes, 1-8 No 1)
Copy protection mechanisms CSS CPPM , digital watermark

1) Because of the still images, there are NTSC and PAL versions.

Playing time

Playing times of frequently used sound modes with DVD-5 and DVD-9
soundtrack Suitability examples DVD-5
(single layer, single sided) 		DVD-9
(two-layer, one-sided)
LPCM MLP 1) LPCM MLP 1)
Mono 16 bit / 44.1 kHz Audiobooks (384 kbit / s) 14:45 h 29:30 h 26:45 h 53:20 h
stereo 16 bit / 44.1 kHz CD compilations (768 kbit / s) 7:20 h 14:45 h 13:20 h 26:40 h
Six-channel tone 24 bit / 48 kHz Soundtracks (3.76 Mbit / s) 90 min 3:00 h 2:40 h 5:25 h
stereo 24 bit / 192 kHz Restorations (approx. 5.2 Mbit / s) 65 min 2:15 h 2:00 h 4:05 h
Six-channel tone 24 bit / 96 kHz Studio albums (approx. 7.8 Mbit / s) 2) 90 min 2) 2:40 h
1)Compression ratio depends on the piece of music; 2: 1 was assumed here.
2) Exceeds the maximum permissible data rate of 9.8 Mbit / s.

In addition, there are rarely DVD-10 (single-layer, double-sided with HDAD), DVD-14 (single-layer on side A, double-layer on side B) and DVD-18 (double-layer, double-sided).

Channel combinations

Due to the maximum data rate of a DVD of 9.8 Mbit / s, the following maximum number of channels results when the sampling rate is fully utilized by the individual channels:

Linear Pulse Code Modulation (LPCM)
Sampling frequency resolution
16 bit 20 bit 24 bit
44.1 kHz 6th
48.0 kHz
88.2 kHz 6th 5 4th
96.0 kHz
176.4 kHz 3 2
192.0 kHz
Meridian Lossless Packing (MLP)
Sampling frequency resolution
16 bit 20 bit 24 bit
44.1 kHz 6th
48.0 kHz
88.2 kHz
96.0 kHz
176.4 kHz 6th 5 4th
192.0 kHz

Optional functions

  • The Meridian Lossless Packing (MLP) already mentioned above for lossless compression
    • enables long playing times (e.g. for audio books ), although data reduction à la DD or dts is missing.
    • is necessary for all modes whose uncompressed data rate is otherwise above 9.8 Mbps.
    • and the future prospects of DVD-Audio: HD-DVD uses Dolby TrueHD (an MLP derivative) as the mandatory lossless sound format. As a result, there must be a TrueHD decoder in every certified HD DVD player. This is similar to AC-3 and LPCM on DVD-Video, where every DVD-Video player must be able to handle these "mandatory formats" (in Europe, MPEG-2 audio is also added). As a result, HD-DVD devices would be predestined DVD-A players, provided that the manufacturers enable this additional feature.
  • Copy protection: Contents on a DVD-Audio, i.e. everything in the AUDIO_TS folder, can be protected against unwanted distribution and duplication by several digital copy protection mechanisms at the discretion of the publisher .
    • The CPPM process ( Content Protection for Pre-Recorded Media ) of 4C (a consortium consisting of IBM, Intel, MEI and Toshiba) is used as the outer protective layer . Player and disc exchange 56-bit keys to agree on playback. In addition, a black list on the medium is used to check whether the "Player ID" has not already been compromised. If this is the case, there is no playback. CSS II was originally intended for this application; after the appearance of the DeCSS computer program , however, these plans were discarded and a delayed product launch in 2000 was preferred in order to find a better method. In the meantime, CPPM is also said to be “cracked”.
    • The inside protection is a digital watermark from Verance. For this purpose, there is additional inaudible information in the audio stream, primarily to impair analog copying.

The use of both or even just one copy protection option is not mandatory for industrially manufactured DVD-Audios either.

As on a CD (and DVD-Video), data outside the AUDIO_TS and VIDEO_TS directories can also be stored on a DVD-Audio for computer use. One possibility is to save the audio data with reduced data in a so-called Compressed Zone DRM -protected.

CD-DA and DVD-A on one disc

Structure of a DualDisc .

The so-called flip disc ( dual disc ) is a sandwich of a conventional audio CD and a DVD-Audio; however, most are CD-DA / DVD-V combinations. However, due to their thickness (1.2 mm + 0.6 mm), these discs do not conform to the standard. This leads to problems with devices that clamp the CD on the laser side.

A version is also conceivable that has a layer that is transparent to red light and is 0.6 mm deep for DVD-A players and a fully reflective layer is 1.2 mm deep for CD players. However, problems arise with DVD-Video players that first look for the DVD layer and cannot find anything there. The hybrid Super Audio CD as a competitor is based on this principle .

Advantages and disadvantages of the audio CD

Comparison of runtimes for audio CD and DVD-Audio
CD DVD5 DVD9 DVD10 DVD18
PCM 16bit 44.1 kHz stereo LPCM
80 min ≈7 h ≈12 h ≈14 h ≈24 h
MLP 1)
≈14 h ≈24 h ≈28 h ≈48 h

In stereo recordings, there are practically no tonal differences between a conventional high-quality CD and a DVD-Audio, so that for these reasons the preference for DVD-Audios over CDs cannot be justified.

Proven technical advantages

  • longer playing time than that of the CD-DA
  • discrete lossless multi-channel technology possible
  • The original version of the RedBook standard allows quadrophony , but this discrete four-channel option only exists on paper, since neither such media nor devices have appeared. Dolby Surround , Dolby PL I, II and IIx give a first taste of more channels, but are matrix-coded. Really discrete multi-channel suitability was only achieved on the CD in the mid-1990s with DTS. Although DTS CDs are largely RedBook-compliant, they are lossy because PCM is not used. An additional DTS decoder is required which is not available in commercially available CD players, but in most commercially available DVD players. If the bit rates are sufficiently high (e.g. 1536 kbps), the playing time of a DTS CD is shorter than that of a normal CD-DA (1441 kbps).
  • DVD-Audio has a higher bandwidth (up to 85 kHz) and a better dynamic range (theoretically up to 147 dB) than the audio CD . Whether this leads to audible differences compared to audio CDs is sometimes doubted, since the recording capabilities of DVD-Audio are beyond the limits of the human ear and conventional microphones and loudspeakers.
  • No (yet) subsequently developed, non-standard copy protection methods as with audio CD, which can cause major compatibility problems with regard to the playability or quality of a medium.

Practical advantages

  • more meaningful portability
according to capacity
portable DVD-Audio players in notebook format or even DVD-A sound systems in automobiles ( Acura ). For example, a dozen audio CDs in a vehicle could be dispensed with in favor of a DVD-Audio - CD changer systems would therefore be obsolete.
according to size
Figuratively speaking, a 12 cm CD-A fits twice on an 8 cm DVD-A. Mini disks (8 cm) are virtually non-existent as DVD-Audio, as there are no portable playback devices in the sense of a DVD-A compatible disk man / walkman , for which the mini disks would be most likely predestined.
better integration of computer data
The DVD-A uses the same file system as the DVD-V and DVD-ROM, namely UDF . As a result, there are no problems as once with the mixed-mode CD, where the first track contained computer data and all subsequent tracks contained audio data. This single-seat type of recording often caused sound problems with early CD player models as they tried to play the data track as well. The shortcoming was solved with the multisession-capable Enhanced CD / CD-EXTRA , here the data track sits in a second session and is "invisible" to CD-Audio players, as they only read the first session with the audio data.
easy archiving of CD audio material
Since PCM is also used with DVD-A, DVD-A archiving copies of audio CDs are not only more space and cost-efficient, but also make more ecological sense than using CDs again. It should be noted that even refinements such as DTS-CDs (multi-channel CDs) or HDCDs (pseudo-20-bit CDs) remain intact on a DVD-A and can also be played back with the necessary decoders.
DVD-A players are actually always universal DVD players
That means: DVD-Vs as well as CD-As can be played. There are DVD-A players that can also play SACDs ( Pioneer , Denon , Oppo ) and DVD-V players that accept SACDs, but not DVD-As ( Philips , Sony ).

disadvantage

  • requires special players that are much rarer than CD players
  • Full control of a DVD-A player often requires a television
  • Complete listening pleasure of a DVD-A usually also requires a new amplifier or receiver, due to the following situation:
Connection options (from player to amplifier)
analogous digital
2 × cinch 6 × cinch S / PDIF 1) (coaxial or optical) Firewire HDMI 2) (from version 1.1)
DVD-Audio 2.0 sufficient sufficient acceptable ideal ideal
DVD-Audio 5.1 insufficient sufficient insufficient ideal ideal
1) Transmission maximum is with stereo PCM 24 bit 96 kHz.
2)Even with an HDMI 1.3 connection, MLP-coded data is decoded in the player and transmitted to the amplifier as an LPCM signal. A direct transfer of the original MLP data to a Dolby TrueHD -capable amplifier is (so far) not possible or not intended.

distribution

The DVD-A is currently (2018) a niche product . In the German sales market, together with the SACD and across all music genres, approx. 100,000 sound carriers are sold per year (as of 2017). In contrast to the DVD-A, which never achieved a decisive breakthrough, the SACD has meanwhile been comparatively successful in the field of classical music and film music. In other markets, too, the DVD-A never achieved the same level of popularity as the CD. In the USA, too, sales from DVD-A sales in 2017 were only around 0.1% of total music sales and around 0.3% of the volume of sound carriers sold. The DVD-A format was aimed primarily at music enthusiasts due to the better technical possibilities. In the case of digitally distributed music, these value the better properties of a higher sampling rate and better resolution. In the meantime, comparably high-quality music recordings, even without the use of physical media, are available for download in special hi-res audio formats such as ALAC , AIFF , FLAC , WAV with PCM raw data or DSD .

Software for the PC

In the meantime, DVD-Audio can also be used on a PC - in contrast to the main antagonist, the SACD , whose HD layer cannot even be read there.

To play

To create

Web links

Individual evidence

  1. ↑ Super audio: only for bats . Stiftung Warentest
  2. ↑ Graphic, music sales via physical media 2017. Bundesverband Musikindustrie eV, accessed on December 16, 2018 .
  3. ↑ US Sales Database. Recording Industry Association of America, accessed December 16, 2018 .
  4. ↑ Hi-Res Audio: The Basics. Retrieved December 16, 2018 .
  5. ↑ plugin
  6. ^ Website of the Burn project