|  Digital
Theater Systems (DTS) is more than just a household name in the multi-channel
audio industry. The company was founded back in 1990 and within a few years became
one of three theatrical digital audio formats. Those who heard DTS for the first
time were impressed with the audio quality, which was commercially introduced
in 1993 with the release of Steven Spielberg’s blockbuster Jurrasic Park.
Soon after, DTS audio appeared on laserdiscs and videophiles had reference quality
5.1 sound to compliment their picture. In 1997, when DVD-Video was launched, DTS
was not included as part of the mandated audio formats and Dolby Digital got a
head start with what became the most successful video format in history. Regardless,
DTS was determined to get their format on DVD-Video and within a relatively short
time, DTS audio began appearing on many of the major hollywood releases. This
would not have happened if DTS was not successful in getting their technology
into consumer hardware. This included DVD players recognizing the DTS audio packets
as well as home theater receivers and processors being able to decode it. Initially,
most of the home theater products only carried Dolby Digital capabilities, but
as the demand for DTS increased, mainstream products began including the technology.
As processors became more powerful both technologies were integrated into a single
chip. Since then, DTS has become a standard for virtually all home theater and
multi-channel audio products. Now DTS is available in a wide variety of A/V products
including 5.1 encoded CDs, DVD-Audio, DVD-Video and a select number of high definition
D-VHS tapes released from Fox Home Entertainment. We've listened to a few of these
new DTS encoded D-VHS tapes recorded in the full 1.5 Mb/s data rate and we can
confirm that the audio quality is superb.
Encoding
DTS technology onto CD or DVD media has traditionally required an expensive DTS
hardware encoder or plug-ins for professional audio software packages such as
Steinberg's Nuendo. DTS has recently introduced their new Pro Series Surround
Encoder software for audio professionals who want to use their digital audio
workstations to create multi-channel DTS recordings. In addition, this package
includes the first commercially-available solution for encoding high quality DTS
96/24 and DTS-ES 6.1 discrete soundtracks. Using the new DTS Pro Series Surround
Encoder, users can create their own multi-channel DTS encoded files by simply
defining the input files and surround configuration. It should be noted that this
software is strictly an encoder and does not do any additional audio processing.
The user interface is intuitive and very simple to use. According to DTS, Peter
Gabriel is the first artist to use the DTS Pro Series 6.1 Surround Encoder
on an upcoming project from Warner Vision International. This software uses the
same high-quality compression algorithms that has made DTS so popular among audiophiles
and movie goers. The
package includes a single install disc that supports both MAC OS X and PC Windows™
platforms. The installation consists of three software components (Java virtual
machine or update, Runtime for the WIBU adapter dongle, and the Pro Series
Surround Encoder software). When the software is installed, three icons, which
include the Pro Packer, Pro Installer, and Pro Encrypter
utility are created. DTS
Packer
 Creating
a DTS encoded file is a simple two-step process that requires the user to first
create a packed agm file. The file is created using the Packer program
that selects the individual audio files corresponding to each individual channel.
The DTS Packer program generates a single agm data file from the
multiple audio tracks. The user defines the Front channels, Back
channels and whether the LFE (Low Frequency Effects) channel is used. Playback
formats include 2.0, 2.1, 3.0, 3.1, 4.0, 4.1, 5.0, 5,1, DTS-ES 5.1 Matrix, and
DTS-ES 6.1 Discrete. When encoding DTS-ES 6.1 Discrete channels the software requires
48 kHz or 44.1 kHz sample rates for the source files. Each of the active channels
are displayed with the corresponding File Name, Sample Rate, Bit
Depth and Track Lengh. If the Sample Rate defined by the user
does not match the sample rate of the input audio file, a red outline will appear
around the corresponding file Sample Rate. Also, if the file Track Lengh
differs from any of the other input files, the corresponding file Track Length
will also have a red outline around it as seen in our test case. The user can
define the Frame Rate by selecting 24, 25, 29.97 drop, 29.97 non-drop and
30. The estimated output file size is also displayed at the bottom of the screen,
which was almost 400MB in our test case with 5.1 96/24 channels. A 3dB Rear
Channel Attenuation checkbox can also be selected by the user. When using
an 88.2 kHz sample rate, the software only allows stereo tracks. Three bit rates
that include 754 kb/s, 1.235 kb/s and 1.509 kb/s are available. Data sampled at
44.1 kHz or 88.2 kHz for multi-channel audio CDs must be encoded at 1.235 kb/s.
Data sampled at 48 kHz or 96 kHz for DVD can be encoded at 754 kb/s or 1.509 Mb/s.
The 1.509 Mb/s data rate fully supports 96/24 audio channels for superior fidelity.
Once the files are defined, the user can select Pack or Pack and Encode
to generate the agm file for the Encoder. The latter option automatically
launches the Encoder once the packing is complete.  DTS
Encoder
Once the packed agm file is created, the Encoder
program is used to generate the DTS file. The DTS Encoder program accepts
the single agm file created by the Packer program and generates
an encoded DTS output file (wav, dts or cpt) defined by the user. The DTS Wave
Format (wav) uses an Intel byte order and wav header. The Padded Format
(dts) is a raw file with no header information and zero padding to fill
frames. The Compact Format (cpt) uses a Motorola byte order with the timecode
removed and a start time present. The cpt format is needed for the Apple
DVD Studio Pro V3.0 software. The wav format is typically used for 5.1
or 6.1 music surround discs where no video is present. The dts and cpt
formats are used for DVD authoring. DTS recommends users read the DVD
Authoring for DTS document for those interested in creating DTS DVDs.
Based on the
source file packing options, the sample rate, channel configuration and bit depth
are displayed. The user has the option of encoding the entire source file by checking
the Whole Source File checkbox or a portion of the file defined by the
Source Start Time and Source End Time. The user can set the Dialog
Normalization value at this point to set the metdata used to control the playback
level of the decoding equipment. It has no effect on the encode or decode process.
DTS
Encrypter
 The
DTS Pro Encrypter application is included with the DTS Pro Series Surround
Encoder package and gives the user the ability to encrypt a packed DTS agm
file. This allows the user to transmit the packed file over an unsecured network
without worrying about it being intercepted by an unauthorized party. The software
requires the user to enter a password consisting of at least eight characters.
The process takes a little more than a minute to process depending on the speed
of the computer being used. The same application is used to decrypt the encrypted
file and is automatically recognized by the software based on the file extension. Creating
Surround Mixes
The DTS Pro Series Surround Encoder does not include
any capabilities for creating surround mixes. It is strictly used to convert your
final multi-channel audio files to a single DTS encoded bitstream. We created
some of our own 5.1 recordings using Steinberg's Wavelab 5 and Cakewalk's SONAR
4 software. Multi-channel surround processing can be difficult and these products
offer a full array of features for those who need to control their mixes. Once
the source files were created, we used the Pro Series Surround Encoder software
to pack and encode the files. All of our source files were 16-bit sampled at 44.1
kHz. The packing/encode process was simple and fast and created a single WAV
file for the final CD burn. Since
our dated Parasound AVC-2500u preamplifier does not have the capability to decode
some of the newer DTS formats, we decided to encode our sample files using the
standard DTS 5.1 format for CD at 1.235 kb/s. Using our Sony DVP-NS900V DVD/CD
player, we loaded up the newly recorded disc on our system and it worked perfectly.
The fidelity was excellent with each channel matching the original source file
with no noticeable degradation. Unfortunately, we didn't have the resources to
create a multi-channel DTS DVD. Conclusion
The DTS Pro
Series Surround Encoder is a no-frills software package that allows users
to create DTS encoded bitstreams for both CD and DVD authoring. The software includes
the Pro Packer, Pro Encoder and Pro Encrypter, each of which
work as advertised. We found the software easy to use and quite intuitive. Whether
you need DTS Digital Surround 5.1, DTS-ES 6.1, DTS 96/24 or DTS for DVD-Video,
the DTS Pro Series Surround Encoder is a simple way to get your audio
mixes into the DTS format. DTS
also offers the Pro Series Network Encoder for multi-user facilities that
is designed to deliver seamless integration with Xserve RAID systems with up to
99 users on either Mac or Windows workstations. -
Kevin Nakano |
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