Meridian 565 User Manual Supplement for DTS

Meridian 565 User Manual Supplement for DTS
Introduction
How to use DTS
Meridian have recently released a new hardware
version of the famous 565. The hardware change
includes a new Z3 DSP card.
The Z3 card runs Version 4.x software, and will add
support for all the audio formats of DVD – including
Dolby Digital (AC-3), DTS, MPEG Audio and 24-bit
PCM.
The first release of Version 4 software does not
include MPEG decoding; this will be provided as a
maintenance upgrade.
This sheet supplements your 565 Installation and
User guides and describes how to use the 565 to play
back DTS material.
The information in this sheet will be incorporated into
a new 565 User Manual when the MPEG software
upgrade to your 565 is available. Please return the
enclosed form to register your Version 4 purchase. We
will send you a final manual in due course.
The 565 automatically detects DTS if you play a DTS
CD, LaserDisc or DVD.
When the disc starts playing, the 565 will switch to
one of its DTS presets.
If you subsequently play a different disc (such as a
standard CD or a Dolby Digital LaserDisc), the 565 will
reload another DSP preset – like Trifield or Dolby
Digital (AC-3).
Alternatively, you can manually select one of the DTS
presets at any time. (See page 18 of the User guide.)
Please note: if you do deliberately select a DTS preset,
the 565 will only decode DTS and be silent for all other
formats until the preset is changed.
Installing 565 for DTS
DTS soundtracks are available on CD, LaserDisc and
DVD. In each case the encoded DTS stream is
delivered from the SPDIF cable or optical output of the
player to the 565. There is no need for a demodulator
for DTS LaserDiscs or for Dolby Digital on DVD.
Consequently there is no need to change the way
your 565 is connected; DTS will be delivered from the
digital output of the CD and DVD players or the optical
output of the LaserDisc player directly to the 565, or
562V if one is present. (See page 9 of the 565
Installation guide.)
Please note: the digital signal carrying DTS can be
safely passed through a Meridian 519 Demodulator if
you have one.
The setup procedures for a new 565 are the same as
those outlined in the Installation guide for a 565 AC-3.
There is one additional Config parameter, and some
Config subtleties – as outlined in this supplement.
New presets
The 565 has three new factory presets for DTS. These
are:
• DTS CD – normally used for CDs. This preset will be
automatically called up by 565 if you play a DTS CD
and the 565 source is labelled ‘CD’.
• DTS – for DTS movie soundtracks. The default
settings for Version 4.x assign this preset to the LP
source.
• DTS THX – adding THX processing to DTS movies.
This preset loads automatically when the source is
‘LD’.
In keeping with current guidelines from Dolby, the AC-3
presets are now labelled ‘Digital’ and ‘Dig. THX’. If you
find this confusing, you can label your user presets in a
more helpful way.
DSP parameters
The DSP preset parameters for DTS are the same as
those for Dolby Digital (AC-3), except for ‘Compress’
which is not a feature of DTS. (See page 40 of the
User guide.)
Correct use of the LFE Level control is important with
DTS recordings.
It is conventional for decoders to boost the LFE
signal by 10dB for movie reproduction (this is the
expected setting at the cinema).
Some DTS music material may not expect the normal
theatrical 10dB boost to the LFE signal. If you find the
sound of some material to be particularly boomy, you
should turn this parameter down to ‘LFE –10dB’ or use
the DTS CD preset instead, which has a default LFE
level of –10dB.
When DTS is being decoded, there is an additional
display available on the 565 that shows the encoded
format, like ‘4.0’ or ‘5.1’.
Storing Presets
Once you have customised a DTS preset to your liking,
you can store and name these settings as a User
Preset in the same way as any other DSP preset.
However, there is a very important difference in
functionality: while 565 will allow you to create a DTS
preset – it will not assign it to a source as part of the
‘Store’ process. (See page 30 of the User guide.)
If you want to assign a DTS preset to a source, you
have to do that in Config. (See page 48 of the
Installation guide.)
Why is DTS handled differently?
Unfortunately, to understand this we have to delve into
some arcane technical issues.
Dolby Digital and MPEG are both ‘flagged’ as nonaudio in the data stream and so devices like 565 or
digital/analogue converters (DACs) know not to play it
as normal audio by mistake. (This same method is
used to prevent you playing back CDROMs as audio in
a CD player.)
If, for any reason, compressed streams are directly
played as audio, the result is a loud hiss.
Like Dolby Digital and MPEG, DTS is a compressed
(non-PCM) signal.
Meridian Audio Limited, Stonehill, Stukeley Meadows, Huntingdon, Cambs, PE18 6ED, England
Tel: +44 1480 434334 Fax: +44 1480 432948 Web: http://www.meridian-audio.com
Meridian 565 User Manual Supplement for DTS
DTS streams on the other hand are not flagged in
this way; consequently normal DACs and decoders
have no direct method of preventing you hearing the
compressed stream as a loud hiss.
The Meridian 565 detects the DTS signal and
switches to a DTS preset as quickly as it can. However,
even the 565 needs a short time to be sure that this
really is DTS. So, when you play a DTS LaserDisc you
may hear the compressed signal as a short burst of
hiss before DTS is identified. As we have explained,
this is an unavoidable limitation of the way DTS is
delivered, not of the 565.
In Version 4.x software we have provided some very
useful workarounds, as described in the next four
sections.
Pre-loading DTS
Automatic DTS operation
If you want to ignore the short hiss that may occur at
the start of LaserDiscs, then you can just use the 565
as before.
CDs will always behave well because of the default
DTS delay.
If you follow this method, the 565 will load one of its
DTS presets automatically if a DTS signal is detected.
The preset that gets loaded depends on how the
source is labelled – as described below:
•
Label is ‘LD’ – loads DTS THX
•
Label is ‘CD’ – loads DTS CD
•
All others – loads DTS
For example, you can therefore force the 565 to use
DTS CD with the CDR source, by re-labelling it CD as
described on pages 48–49 of the Installation guide.
Manually pre-loading a DTS preset, as described
earlier, avoids the hiss. To further assist, we have set
up the LP source to automatically load DTS for
LaserDiscs. So, if LP is selected before playing a DTS
LaserDisc, the DTS preset will be automatically loaded
and no hiss will be heard.
Obviously the LP source can be re-configured
differently if you need it.
Using a 562V with the new 565
DTS Delay
If you have a Meridian 518 Digital Processor, this will
de-jitter a DTS signal for optimum sound quality.
However the resolution enhancement features of the
518 are not appropriate as DTS is a compressed digital
stream, not standard digital audio. Hence your 518
should be switched to Bypass mode prior to listening to
a DTS CD or LaserDisc.
There is an upgrade to the 518 software, Version 1.2,
which allows it to detect a DTS stream. In this case, the
518 automatically selects Bypass when DTS is
detected.
Version 1.2 adds four DTS modes to the 518 which
can be assigned to sources in Config. The modes are:
•
DTSMU – 518 mutes on receipt of DTS (used
when 518 is a preamp).
•
DTSCD – detects DTS with a normal strategy and
selects Bypass.
•
DTSLD – detects DTS with a rapid strategy and
selects Bypass.
•
DTSMA – mastering processor mode ignores DTS.
There is an additional parameter in the source Config
of the 565. (See page 48 of the Installation guide.)
The display will read:
‘CD DTS Del. Y’.
This may be set to ‘Y’ or ‘N’. Setting it to ‘Y’ adds a
32ms delay to the audio for that source. Engaging this
delay allows the 565 time to detect a DTS signal before
it is played out, and therefore prevents the short hiss
occurring as the disc starts playing.
Setting DTS Delay to ‘Y’ is the ideal and
recommended solution to playing DTS from CD. This
setting is not recommended for video sources (such as
LaserDisc or DVD) because an additional 32ms audio
delay is equivalent to one video frame, and may affect
the Lipsync with the picture. (See page 28 of the User
guide for an explanation of Lipsync.)
When you Type the 565 (page 20 of the Installation
guide), the default settings for DTS Delay are ‘Y’ for
CD, Radio and CDR, and ‘N’ for LP, TV, Tape1, Tape2,
Cable, DVD, VCR1, VCR2 and LD.
Dedicated DTS sources
As we described earlier, you can attach a DTS preset
in Config to one of the sources. The default
configuration attaches DTS to the LP source.
When such an attachment is made, the 565 will only
play DTS material for that source.
You can attach any of the three factory DTS presets,
or any DTS user preset in Config. (See page 48 of the
Installation guide.)
There is an upgrade to the 562V software, Version 1.8,
which includes a DVD input for video and digital audio,
and also supports the LP key for DTS LaserDiscs.
Whilst not necessary to enjoy DTS material, it is
available from Meridian dealers.
Using 518 with the new 565
These can be selected according to Type as follows:
•
Type 0 – all sources DTSMU
•
Type 1 – all sources DTSCD except DVD and LD
which are DTSLD
•
Type 2 – all sources DTSMA
© February 1997
Registered trademarks: “THX” and “THX Cinema” Lucasfilm Ltd; “Dolby”, “Pro Logic” “Dolby Digital”and “AC-3” Dolby Laboratories Licensing Corporation;
“Ambisonic” Nimbus Records Ltd; “Trifield” Trifield Productions Ltd; “Meridian”, “Boothroyd Stuart Meridian” “LipSync”and “Meridian Digital Theatre”
Meridian Audio Ltd; “DTS” Digital Theatre Systems Inc.; “DVD” Toshiba and the Ten Companies.
Meridian 565 User Request
Please register your Version 4 565 with us. We can then send you a complete user
manual when MPEG is released. You can register in the following ways:
• Complete the details below and either mail or fax this sheet to Meridian Audio in the
UK or Meridian America in Atlanta.
• Register by email by sending the necessary information to list4@meridian-audio.com
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Meridian Audio Limited, Stonehill, Stukeley Meadows, Huntingdon, Cambs, PE18 6ED, England
Tel: +44 1480 434334 Fax: +44 1480 432948 Web: http://www.meridian-audio.com
Meridian America Inc., 3800 Camp Creek Parkway, Building 2400, Suite 112, Atlanta GA 30331
Tel: +1 (404) 344-7111 Fax: +1 (404) 346-7111