Bob Stuart answers Questions on Meridian`s 568 and 562V.2

Bob Stuart answers Questions on Meridian`s 568 and 562V.2
Bob Stuart answers Questions on Meridian’s 568 and 562V.2
What is the Meridian 568 Surround Processor?
The 568 is Meridian’s latest and most advanced 500 Series Surround Processor! It is a great
performer and includes features that will ensure access to state-of-the-art audio performance
for many years to come.
Why should I consider a 568?
It has an unbeatable pedigree and outstanding performance.
Meridian was the first company to make an all-digital surround processor when it introduced
the 565 in 1994 and it rapidly became and remained the benchmark processor. The superior
technology, design approach and sound quality provided by 565 was widely acknowledged
and it received an amazing total of 25 industry awards including ‘Home Theatre Decoder of
the Year’ by Home Entertainment in both 1995 and 1996, the prestigious EISA award for
‘Home Theatre Decoder of the Year’. Not least, it holds a Stereophile Class ‘A’ rating.
The proprietary DSP software we developed for 565 has been continuously extended and
refined and is used in our other world-beating DSP surround controllers: the Reference 861
and the hugely popular 561. The AAA-rated Meridian 861 Reference Surround Controller is
our flagship surround controller and it is the standard to which all aspire.
The 568 has the benefit of many of the techniques and features pioneered in Meridian 861
and, like all our products, has been built with the future very much in mind. With 568’s
pedigree and 562V.2’s flexible and transparent handling of audio and video formats, the new
combination represents a tour de force – a very elegant solution.
You refer to Surround Controllers and Surround Processors. What’s the difference?
In our terminology a Controller is a Processor that also controls all the audio (and video)
inputs, provides a tape copying system – and maybe 2 or 3-room functionality.
568 is a Processor. It has quite a few inputs and may be all you need. But if you want more
inputs, a tape loop, video switching or 2-Room+ you should use it with its partner – the new
Meridian 562V.2 Multimedia Controller.
Quickly list for me some of the key features of 568.
24-bit 96kHz DACs and 96kHz Audio Processing
High resolution upsampling to 88.2kHz or 96kHz 24-bit
FIFO memory-based dejittering system (previously only available in the 800 Series)
Eight analogue outputs plus balanced outputs for the front three channels
Eight digital outputs for connecting to Meridian’s astonishing DSP speakers
Meridian High Resolution (MHR) output to Meridian DSP speakers
Flash Memory for easy software updates and PC set-up
Expansion port for DVD-Audio interface upgrade
Two analogue and four digital and one optical inputs
Receives MHR on digital inputs
Composite or S-Video pass through for OSD (on-screen display)
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
Does Meridian make other Surround products?
Yes, the 568 joins a distinguished family that includes 561 and the extremely flexible 861
Reference Surround Controller.
I’ve heard a lot about Meridian Digital Theatre. What is it?
Meridian Digital Theatre is a system built using Meridian DSP Loudspeakers and one of our
Digital Surround products like 568, 561 or 861. It also includes source products like 508, 504
or the 800 Reference DVD Player.
The huge advantages offered by a Meridian Digital Theatre include incredible transparency,
musicality and solidity in the sound that results from keeping the signal in digital form all the
way from the disc to the loudspeaker.
A Meridian Digital Theatre is designed and built with our fanatical attention to detail: as a
result you get sound that cannot be equalled and it operates beautifully as a whole.
Meridian is still the only company to make all the components necessary to build such
advanced home theatre or music surround systems.
Sound issues...?
What is DSP?
DSP is Digital Signal Processing. 568 does all its magic in the digital domain. So digital
signals from sources like CD, DVD, DSS and DTV remain in digital form and this maximises
their quality potential.
Most other products use DSP chips that have built-in processing algorithms optimised for
mass-market applications. Frankly, we cannot be satisfied with this approach.
Meridian sets very high standards of performance and has been unique in fitting very powerful
general-purpose audio computers, and only using decoding and other algorithms developed
uniquely in house.
As an example of where we differ, off the shelf DSP solutions in other products will operate
with between 16 and 24-bit precision. In the 568 we will often use 48 or occasionally 72 bits to
guarantee transparency.
This approach has always been applied to our Surround Controllers, Processors and DSP
Loudspeakers. Consequently the sonic performance is outstanding and the flexibility that
allows the user to get the best from each installation is unparalleled.
Because we are independent in generating the DSP code, our customers can always obtain
upgrades from us to keep up with the latest sources.
In the 568 we use four powerful audio computers to decode the incoming signal, to create the
many different sound fields, to render the audio exactly for the speaker layout and positions
you have chosen. It is also used to protect those speakers against overload and not least to
de-jitter, to upscale and to enhance resolution. A very powerful overall approach that keeps
our customers happy and our competitors worried!
What exactly is Upsampling?
Upsampling uses a complex DSP filter to double the rate of samples from the source so that
the subsequent system components can more accurately reproduce the sound. 568 combines
Resolution Enhancement with upsampling. For example, CD (which starts as 44.1kHz 16-bit
audio) is upsampled using our proprietary DSP to 88.2kHz 24-bit and DVDs with 48kHz audio
are upsampled to 96kHz 24-bit.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
Meridian is famous for its Resolution Enhancement technology in products like 518 and 618
where it is used to make the finest CD releases.
The upsampling and Resolution Enhancement can be applied to any 44.1kHz or 48kHz signal
fed into 568.
How powerful is the DSP computer in 568?
The 568 provides 180MIPs in 4 separate powerful DSP chips. You will only find more
processing in the Reference 861.
Three of these processors are on plug-in cards so, over the years, if necessary, we can
economically increase the processing power and even add a fifth processor to this engine.
10 What does the DSP do in 568?
The Meridian 568 is a powerful 8-channel music computer with complete analogue and digital
conversion capability. The on-board DSP contributes to the outstanding sound quality through
a proprietary FIFO memory-based dejittering process. DSP is also used for upsampling,
downsampling and resolution enhancement.
DSP is used to create and optimise the sound. 568 has sixteen different programmes (we call
them Presets) that are used in different circumstances. The Presets in 568 fall into three
categories: Logic, Music and Discrete (5.1 and 7.1 formats).
DSP is also used to upscale material (for example from 2 to 6 channels, or to add sides). It
also provides sophisticated bass management, a LipSync™ function to trim delay in cinema
dialogue, setup calibration tones, and a number of other features.
11 Can you say more about Logic modes?
The 568 provides four DSP options specifically designed for reproducing stereo film
soundtracks. Three of these Presets ProLogic, THX Cinema, and TV Logic are designed for
Dolby Surround encoded material. Most films, and increasingly studio and TV features are
encoded using Dolby Surround.
The 568 Digital Surround Processor follows the Meridian philosophy of performing the entire
signal processing digitally, and the Dolby Surround decoding operates purely in a digital mode
with 24-bit precision. It was natural that when Meridian turned their attention to ProLogic and
THX, the only way they could satisfy their exacting standards for clarity, transparency and
function was to develop the whole thing from scratch using only the best hardware and
software DSP techniques.
The ProLogic system uses psychoacoustically optimised directional enhancement to
increase the separation in both left–right and front–back directions. It does this by
continuously calculating the position and degree of the currently dominant sound. This sound
is then steered to that position in the image. This technique is very successful for cinema and
other dramatic material.
The THX Cinema DSP Preset provides ProLogic decoding followed by the additional THX
Ultra signal processing refinements developed by Lucasfilm Ltd.
The THX extensions to ProLogic decoding are designed to provide a better match between
the sound of the movie theatre and a home cinema in the following ways:
The front channels are re-equalised to correct for the higher treble often found in film
The surround channels are frequency-corrected using a timbre-matching process so
that sounds moving front–back are more convincing.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
The surround channels are decorrelated to break up any artificial localization of the
rear signals due to the speakers being nearby. In the 568 Digital Surround Processor
our proprietary decorrelation algorithm is optimised to give a spacious surround
sound that has no artifacts disturbing to music or other sensitive sounds in the mix.
The time synchronization between loudspeakers is adjusted to compensate for the
fact that the speakers in a home system tend to be a lot closer to the listener than in a
movie theatre.
TV Logic is a logic Preset, with user-adjustable steering, that can give higher intelligibility and
a more appropriate spatial presentation for studio-based TV material.
The remaining Logic Preset, Mono, is designed for films with mono soundtracks. The Mono
Preset also offers the option of an Academy filter to correct the bright sound prevalent in
early mono films.
568 allows you to select a particular speaker layout when using Logic modes. (See Q. 23.)
12 What are Stereo Surrounds?
ProLogic is a surround-decoding algorithm that uses a steering method to localize a sound in
the front stage and also to locate sounds behind the listener. It works very well. However, in
ProLogic there is only one surround signal – the surround signal is mono even if it is played
over two speakers. This is the main reason that THX Cinema uses a decorrelation technique
to prevent the surrounds appearing to be directly behind the listener when ‘envelopment’ is
The ProLogic Preset in 568 has proprietary extensions that allow the steering to include the
surrounds. So, whilst you can select a standard Mono surround signal, the DSP in 568 is
capable of steering surround sounds individually through all 7 horizontal speaker locations.
There is a menu that lets you choose ‘Steered All’.
‘Stereo Surrounds’ has been a feature of Meridian Surround Processors for a number of
years and this playback can be hugely more involving on movies and exciting on music. In
many ways this goes beyond the effects being introduced in EX – but only operates on PCM
or analogue inputs for now. (See Q. 16.)
13 Music is really important to me. How does 568 deal with music?
Music is the most important source for us too: our first interest in surround was to improve
music playback.
‘Stereo’ was not invented as a 2-channel process. The inventors of stereo all advocated at
least three loudspeakers. For many years we lived with a severe compromise: – 2-channel
stereo dictated by the inability of the LP to deliver more than two channels.
Before the DSP era it was very difficult to make significant returns to real – i.e. ‘solid’ stereo.
That has now changed. Meridian has pioneered its now-famous music-processing modes like
Music and Trifield out of a sincere belief (and repeated demonstration) that music – even
when it is distributed on a 2-channel disc like CD – quite simply sounds more lifelike and
involving if played back on a great surround system using (of course) the right processing.
Once you understand that there need be no definite connection between the number of
channels coming in and the number of speakers used to render the sound field you will begin
to understand what we are doing. Needless to say our very highest standards of both
psychoacoustic and DSP design are used for music.
If for no other reason, get a surround system based on 568 (or 561 or 861) to give you a
whole new level of enjoyment of music.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
The 568 is also one of the very few surround products to offer Ambisonic UHJ decoding.
This 3-D music format is very satisfying – although discs are a bit rare. We hope that will
change now that MLP can deliver real B-format Ambisonics.
The 568 has SuperStereo and also offers Music Logic – a ‘steered’ mode that is fun on
some non-acoustic material.
For those for whom ‘pure stereo’ still means 2-speaker, then of course 568 offers Direct and
Stereo (and Mono for extremists).
568 allows you to select a particular speaker layout when using Music modes. (See Q. 23.)
14 What about discrete 5.1 and 7.1?
Today discrete multichannel comes in compressed as Dolby Digital or MPEG or DTS or
Meridian’s discrete decoders, using custom DSP code are the most powerful on the market
and pass all the most extreme bitstream tests for all these formats. The discrete decoders in
568 can provide up to 24-bit data (depending on the system).
The 568 exploits all the options of the discrete formats: e.g. in Dolby Digital we support all
types of Dialog Normalisation and Dynamic-range control with features like compression to
assist late-night viewing.
568 allows you to select a particular speaker layout when using 5.1 modes. (See Q. 23.)
15 How does THX fit in?
Lucasfilm’s THX Cinema has a lot to offer on both Logic and Discrete sources of movie
soundtracks. If you are interested to build a THX system then 568 has all the signal
processing in place to comply with THX Ultra requirements for ProLogic, Dolby Digital, DTS
and MPEG.
16 What about EX?
Lucasfilm’s EX is a proposed extension to movie sound that adds a centre rear channel
(which can be played back either through a discrete speaker or as a phantom image between
two rear speakers).
The Stereo Surrounds option in the 568 ProLogic and THX Cinema modes already provides
fully steered surrounds (see Q. 12).
Extending 568 to decode EX is exactly the kind of thing you might expect to see in a future
software upgrade (see Q. 78). We aren’t promising this until we see a number of titles, but if
the format succeeds we will certainly support it.
17 What is a Preset in 568?
As I described in Questions 11, 13 and 14 the 568 has a large number of DSP programmes
that we call Presets.
Each Preset comes with an interesting number of menu items that allow you to adjust many
features of the playback. You can usually trim bass, tilt, balance, as well as centre level and
delay, surround level and bandwidth. In some Presets you can also adjust decoding
parameters like steering, seating position, dynamic-range control and so on.
In 568 you can build your own Presets based on the built-in ones. If you have worked out a
combination of menu settings that you want to keep you can store it as a new Preset, with a
name you choose. You can also attach it as a default to a Source (like CD, DVD, TV etc.).
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
In fact each Source has a total of five attachments – each telling the 568 which Preset to use
when the incoming format is PCM, Dolby Digital, MPEG, DTS or MLP.
18 OK, so what do you mean by Source?
There are 12 Sources selectable by the 568’s Source button and by the 12 Source keys on
the MSR (Meridian System Remote): CD, Radio, LP, TV, Tape1, Tape2, CDR, Cable, DVD,
VCR1, VCR2 and LD. In Meridian systems the process of selecting a Source can also be
made to control many operating parameters.
19 What do you mean then by Phantom Source?
When you select a Source in a Meridian system, the 568 will look up its settings that you have
stored either through front-panel or computer configuration (see Q. 70). Each Source is userconfigured to one physical input (analogue or optical) on the back panel and the 568 will
select that input and attempt to detect and lock onto the incoming format.
Now, although each Source attaches to one physical input it does not mean that other
Sources cannot use the same input. There is no reason why the 568 shouldn’t use the same
input (e.g. D1) for all the system Sources. This would mean that when you press CD you
would get the same signal as when you press DVD.
Why would you do that? Well the reason is that each Source selection also causes 568 to
load a Preset. You may want to connect a DVD player to the D1 input and use the Trifield
Preset when playing a CD but the ProLogic Preset for a DVD. By making Trifield the default
for Source ‘CD’ and ProLogic the default for ‘DVD’ you now have a rapid way to change all
the settings of the 568. The method applies system-wide so in this example the 562V.2 could
be set up to turn the video off when CD is selected.
We call this process Source Phantoming -- the creation of phantom sources because it
appears you have more than one player.
Phantom is one kind of abstraction that the 568 setup uses to make the system really easy to
use on a day-to-day basis, Layout is the other – this is discussed in Q. 23.
20 What is Bass Management?
Bass Management refers to a number of signal-processing operations that are used in 568 to
optimise the low frequencies in the final sound.
In many systems, and for formats like PCM or Logic, this involves using precision DSP
crossovers and combiners to move the bass from speakers that have less capability and into
speakers that can really deliver the frequencies and levels.
In 568 you can choose to use subwoofers only in certain circumstances (like Music, Logic,
5.1) and to have different crossover frequencies applied in each case. (See Q. 23.)
The discrete 5.1 movie formats like Dolby Digital can deliver much more low frequency bass
than any of the Logic or Music formats. In fact, the 5.1 signals have the potential to require a
16-fold increase in bass power handling in a system.
Although the Dolby’s Digital, MPEG and DTS studio encoders limit the total bass level to
around +15dB, the resulting bass energy can still be incredibly demanding for even the very
biggest systems and, equally important, may be disastrous for other, less capable, speakers.
In fact this is exactly how it can be configured when all signals come via a 562.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
The Meridian 568 incorporates a very sophisticated series of bass protection schemes for
Digital Surround formats. The user can control the overall amount of LFE added in. Also 568
has a bass limiting function to control the total amount of bass passed to the system.
As well as the overall bass protection, the 568 can simultaneously monitor all eight speaker
outputs. If the signal demands more bass than a speaker can supply, a proprietary, psychoacoustically optimised limiting filter momentarily and elegantly reduces the load on that
speaker. This unique protection method means you can get the most out of all the speakers in
the room without any fear of damage or unpleasant overload noises.
21 Why would I want to delay my speakers?
If you are thinking of getting Meridian speakers you shouldn’t delay!
But seriously, the 568 has individually adjustable digital delays for each output and these are
used to optimise the sound.
When you calibrate the system (see Q. 71) one of the options allows you to tell the processor
how far away each speaker is from the listening position. 568 will then use its delay lines to
make sure that the sound arrives at the same instant from all the speakers. This level of
sophistication adds immensely to the image realism and involvement you get in sound fields.
It also ensures that the sounds from all the speakers add up in just the right way.
22 What is LipSync™?
LipSync™ is a proprietary Meridian feature that allows you to get the best synchronisation
between picture and sound in your system by allowing you to adjust the delay between the
sound and the video image by up to one video frame.
We are quite sensitive to time differences between the picture and sound. On movies it is
disturbing if there is an obvious time difference between speech or sound effects and the
picture. It is almost always the case that storage or broadcast systems delay the picture more
than the sound and so the LipSync control in 568 allows you to delay all the sound coming out
of 568 by up to one video frame (1/30 second or 30ms) to re-align it.
Most movies are mixed for a viewing distance of 30 feet, and when viewed from 12 feet or
less the sound arrives too early, having a disconcerting effect. Using the LipSync control you
can add an overall delay to the sound to accommodate your closer home viewing distance.
Sound travels about 1 foot in each millisecond, so 568 allows you to adjust the distance in sixinch (0.5ms) increments.
Many TV broadcasts delay the picture by half a video frame, and can benefit from a LipSync
setting of 12ms.
In the PC setup for 568 (see Q. 70) you can also set a Frame Sync parameter. This is useful
if you have an advanced video processing system, e.g. a line doubler, digital video processor
or interpolating device that delays the video significantly. For each Source you can set an
additional overall audio delay of up to 7 video frames (210ms), which is more than enough to
accommodate the most sophisticated combination of video processors and display devices.
Of course, not every actor in a movie is great at getting the voice-over right. In movie
production all the dialogue is ‘re-spoken’ and added in a sound post-production phase long
after the scenes are shot.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
System design …?
23 You talk about Layouts. What do you mean?
We are referring to speaker layouts.
Like all Meridian Surround Processors, the 568 gives you incredible flexibility in choosing a
speaker arrangement. 568 has eight outputs and they can be configured to drive Left, Centre,
Right, 1, 2 or 4 surround speakers located at sides and rears and up to three subwoofers.
An important aspect in a system is bass management. You may decide to fit some speakers
that are larger (i.e. more bass handling capacity) than others. It isn’t uncommon for a centre
or surround speaker to be smaller than the main left and right speakers. That sort of
information can be fed into the 568 and it will make the optimum use of the bass capacity of
all the speakers and, at the same time, protect small speakers from overload.
Some people do not want to use subwoofers for music – in fact you may have main speakers
that can handle all the bass (hence low-frequency spatial information) for both Music and
Logic applications and want to listen to these formats in this way: perhaps only adding in
subwoofer reinforcement for 5.1 movie formats. With other surround controllers this would be
a nightmare of reconfiguring every time you listened to something new.
With 568 this kind of flexibility is built right in. Better still it is automatic and attains the highest
audio quality ideals for every combination of Source, Preset and Format.
When you configure the 568 you have the option to use a centre speaker and subwoofers
differently for movies, for music and for Logic and discrete formats.
This customisation even extends to choosing different subwoofer crossover frequencies for
Music, Logic and 5.1. This unique and particularly powerful feature allows very fine tuning of a
system that includes subwoofers with often startling benefits for Music.
Once set up, you can forget about it because the 568 will make the Layout changes
24 Do I need Meridian DSP speakers with 568?
Everyone needs Meridian DSP speakers!
However, the 568 can be used with all types of speakers. It can accommodate conventional
passive speakers used with external power amplifier(s), active speakers and of course DSP
speakers. Not only that, but these speakers can be used in almost any sensible combination
and the 568 can be configured to work with your existing equipment. Of course it blends
intelligently with other Meridian products for ultimate performance and flexibility.
25 Do I need a centre channel?
We think so – and it should be a good one.
If you are lucky enough to be able to install a centre speaker that accurately matches the
tonality of the main speakers then the improvement that a centre speaker will bring to music
will astonish you. Guaranteed!
For movies, a centre speaker to handle dialog is quite important.
Don’t skimp on the centre speaker – sometimes systems are displayed with small, easy-toinstall centres – but the centre takes a lot of load on movies and will affect the whole image
integrity for music.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
26 Do I need subwoofers?
Now this is a more difficult question. The answer depends some on the size of the room. For
small to medium-sized rooms my feeling is ‘there is no subwoofer like no subwoofer’. But I
have a very particular perspective, which is that I want total integrity between high, medium
and low frequencies for music – not just in terms of response – but in spatiality. The spatial
impression of an auditorium is conveyed in a large part by the low frequency ambience –
which is directional.
So for music, undoubtedly the best prescription is to have all speakers capable of reproducing
low frequencies and to eschew a subwoofer. Obviously not all circumstances allow this and
unfortunately not everyone will use 5 or 7 Meridian DSP speakers.
Sometimes you may want to add in a subwoofer for Logic movies. Certainly even I will add in
a subwoofer just to handle the LFE part of 5.1 movies (but keep it silent for any other
material). 568 allows you to take such extreme purist positions – and of course if you like or
want subs that isn’t a problem – you can have up to three and use satellites everywhere.
What does the 568 play…?
27 What can 568 decode?
The 568 can decode all forms and data rates of Dolby Digital (AC-3), DTS, MPEG, MPEG
Surround and Meridian Lossless Packing (MLP).
28 So I can feed 96/24 into my 568?
Yes. The digital inputs support 32kHz, 44.1kHz, 48kHz, 88.2kHz and 96kHz 24-bit. 568 also
supports Meridian’s MHR content protection on its inputs and outputs so that you can be
assured of very high quality content.
29 What is MHR?
MHR (Meridian High Resolution) is a proprietary method for getting the highest possible
sound quality in playback systems that use Meridian components like 568, 800, 861 and DSP
MHR also uses proprietary encryption and anti-copy techniques to ensure secure transfer of
audio streams between elements of a Meridian-only system for the purpose of playback only.
It provides a secure copyright protection environment and has the very important benefit of
lowering jitter and improving sound quality on all material.
30 And does 96/24 come out of my 568?
Yes if you want it to. The 568 will use the highest rate possible on its outputs and high-rate
(88.2kHz or 96kHz) is available on both the analogue and digital outputs (according to your
31 Can I play CDs through 568?
Of course! Nearly all CD players provide an SPDIF 44.1kHz 16-bit digital signal that can be
fed straight into 568. It can upsample CDs to 88.2kHz 24-bit and the results are amazing (see
Q. 8). The 568 has Trifield, Music, Ambisonic, Super Stereo and Music Logic Presets which
are carefully optimised for rendering 2-channel music sources like CD in a surround system.
Of course, if you want to listen to just 2 speakers we provide Direct and Stereo.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
32 What about DVD-Video?
The 568 is excellent on DVD and all the audio formats are supported. Fit a digital connection
between the DVD Player and the 568 and set up the player to provide un-decoded 5.1
material. The 568 will decode and optimise PCM, Dolby Digital, MPEG and DTS from DVD.
33 Can I play VCD or CVCD?
Yes. Depending on the player you may or may not get a digital feed of the MPEG stream. If
you do, 568 will decode it, otherwise the decoded PCM can be used to play back the discs
with Presets like ProLogic or Trifield.
34 Can I play SAD or DAD?
There are a lot of TLAs around these days – but why would anyone call a format SAD? SAD
(Super Audio Disc) and DAD (Digital Audio Disc) are marketing misnomers for DVD-Video
discs that have 96kHz 2-channel audio streams.
The 568 plays these back and with Trifield you can add in a centre speaker for even better
35 Can I play DTS DVDs?
A very small number of DVDs have an optional DTS stream; if your DVD player can provide
this signal the 568 will decode it just like Dolby Digital.
36 Can I play DTS CDs?
Yes. As long as you have a digital connection from the CD or DVD player the 568 will detect
the DTS stream. Because the DTS CDs are not flagged it is useful to set the DTS delay
parameter to help the decoder detect such discs smoothly.
37 Can I play MLP CDs?
Yes. As long as you have a digital connection from the CD or DVD player the 568 will detect
these discs and decode the MLP stream. 568 will also respond to the flags in the MLP stream
and ensure that the correct surround mode is selected. The Meridian 568 will additionally
decode CDs that use MLP to carry Ambisonic B-format encodings.
38 Can I play Laserdisc?
You can feed the analogue or digital outputs of a Laserdisc player directly to 568 (or via
562V.2), which will allow you to play any Laserdisc – including those with mono, stereo, Dolby
Surround or DTS sound tracks.
To get access to any Dolby Digital sound on Laserdisc you will also need a Meridian 519 RF
Demodulator. Meridian’s demodulator is the very best and you should hear what its
additional de-jittering and the upsampling in 568 do to the sound of those discs you thought
you knew.
39 Can I play LP?
568 doesn’t have a phono input stage. However, you can fit an optional phono module to a
562V.2 and not only enjoy your LPs in stereo – you can upscale to surround with Presets like
Trifield. The results will amaze you.
TLA – Three-Letter Acronym!
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
40 Can I play DVD-Audio?
Although the technical standard now exists for the DVD-Audio disc, important issues like copy
protection and the connection interface are still being discussed, so there are no DVD-Audio
players on the market yet. As one of the writers of the standard, Meridian is hard at work on
this. 568 has been designed to flexibly adapt to future formats like DVD-Audio. (See also
question 79).
41 How about MLP?
MLP (Meridian Lossless Packing) is a special lossless coding method that allows higher
quality and more channels to be fitted onto discs. We are very proud that our coding system
has been selected as the mandatory coding method for DVD-Audio.
568 has a full MLP decoder built in.
42 Will it decode HDCD?
No, but HDCDs are CD-compatible and play back fine without decoding.
43 What about DSS?
DSS can provide a digital output and you will experience a huge improvement in sound if you
connect it directly to 568 (or via 562V.2). A nice surprise will be when you hear what an
incredible difference upsampling makes to DSS music stations.
44 What about MP3?
Good question! For the time being we don’t think 568 needs an MP3 decoder because there
isn’t yet an agreed interface for MP3 and it will always be decoded in the players. Connect the
player to 568 and enjoy.
45 Can I play SACD?
Yes. SACD just has a two-channel analogue output, so you can connect it to 568 – or to
562V.2 along with your other analogue sources like VCR, TV, Radio etc. See Q. 78.
46 What is MPEG?
The 568 currently decodes all MPEG audio streams. MPEG shows up in a number of places
– e.g. on PAL DVDs, on VCD and on some satellite and digital radio broadcasts.
47 I heard about 192kHz. Will 568 handle this?
Eventually. Some DVD-Audio discs will use 192kHz 2-channel coding. 568 has an expansion
slot and at some point we will be making a multichannel input module and upgrade package
that will allow high-rate multichannel (including 192kHz) to be fed into 568. See Q 52.
48 I’ve heard about something called DSD. Will that be OK too?
DSD is the coding system used on SACD (see Q 45). Until more aspects of SACD player
design are revealed it is hard to answer this specifically other than to say that the 568
upgrade slot allows for almost any source format to be accommodated.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
49 But my Speakers don’t support 96kHz. What do I do?
No problem. There is more benefit from double speed digital audio the further down the chain
it goes. If you cannot use 88.2kHz or 96kHz digital outputs don’t worry. For now, use the
incredibly transparent downsampling DSP in the 568. If you upgrade your DAC or DSP
speaker then you can turn double speed on again at any time.
Video issues in 568…?
50 Does 568 have video processing?
No, the 568 simply passes video through for the purpose of adding On Screen Display (OSD).
51 What Video inputs are available?
568 has the capacity to pass through either composite or S video, but not at the same time.
The signal paths are shared, so you decide when you install it whether to connect composite
or S.
568 Connections…?
52 Can 568 take multichannel inputs?
The 568 receives multichannel signals now as up to 5.1 or 7.1 encoded with Dolby Digital,
Discrete multichannel is an important consideration for the coming years as newer sources
capable of outputting discrete (like PCM or MLP) on new digital interfaces start to enter the
At this point, connections are not defined for formats like DVD-Audio and the final solution
may include Firewire or other protected interfaces.
568 has an expansion slot that we believe to be quite capable of supporting any of these
future possibilities. So, at some point, we will be making a multichannel input module and
upgrade package that will allow 568 to receive high-rate multichannel (including 192kHz). See
also Q. 47.
53 What audio outputs are available?
The Meridian 568 has eight standard unbalanced analogue outputs for driving eight speakers.
Three of these outputs (for Left, Centre & Right) are also available in balanced form on XLR.
In addition, the 568 has four SPDIF and/or MHR outputs that allow the connection of up to
eight digital or DSP speakers.
Finally the 568 has a bypass digital output which allows the currently selected signal to be fed
to another zone.
54 Has 568 got a headphone socket?
No, it makes little sense to connect headphones to a Surround Processor.
55 Will it handle Firewire?
See Q. 52.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
568 as a Controller…?
56 Can I use the 568 without 562V.2?
Yes, the standard 568 provides 5 digital inputs and two analogue inputs. This is often enough
to put together a complete AV system. If you can manage with these inputs and do not need
the video switching, tape loop or 2-room features of 562V.2 then the 568 is all you need.
57 Right now I have a Meridian 501, 502 – can I use these with 568?
Yes. If you have a 501 or 502 you can use these to gather all the analogue sources for the
system and feed them to the 568. This will be fine as long as the 5 digital inputs on 568 are
enough and you don’t need the video switching 562V.2 provides.
58 Can 568 be the controller for a 2-Room system?
The 568 does not have any signal routing features to function as a 2-Room controller.
However, like all Meridian controllers it supports multiroom displays and integrates into a
Meridian 2-Room Plus system.
59 Can I record from my 568?
Not sensibly. If you want to do any taping we suggest you add a 562V.2.
568 with Digital and DSP speakers...?
60 Can I use 568 with Meridian DSP Loudspeakers?
Yes – and what a system! 568 along with a combination of DSP5000/C, DSP5500/C,
DSP6000/C or DSP33/C builds a Meridian Digital Theatre (see Q. 6).
568 will work with any Meridian DSP speakers of whatever vintage. The new or upgraded
versions of DSP speakers support 96kHz and MHR and that, of course sounds the very best.
61 Can I use 568 with Meridian Digital Subwoofers?
Yes, it works perfectly with Digital Subwoofers like D1500 and D2500.
62 What about older Meridian Digital speakers?
Meridian D600 speakers are more than ten years old. If you want to use them your dealer will
fit an EPROM that allows them to work in the Meridian Digital Theatre.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
562V.2 …?
63 What is the Meridian 562V.2 Multimedia Controller?
562V.2 is a control and switching centre for a digital audio system. Think of it as a preamp for
digital systems. 562V.2 is a recent upgrade to the well established and hugely popular 562V.
562V.2 allows you to control 5 cable-digital, 2 optical and 7 analogue sources in an
installation. 562V.2 has analogue and digital outputs (there are internal A/D and D/A
converters) and it supports analogue, digital and VCR recorders with a separate copy loop.
A 2-Room plus system can also be built around a 562.
The 562V.2 also controls video sources with incredibly high standard studio-grade video
routing and processing. Up to four S signals can be switched to a main output and
independently to two videotape outputs. Up to six composite video sources can be controlled
(also supporting a main and two tape outputs). New in 562V.2 is the processing that allows
conversion of the main and tape S outputs to composite.
562V.2 has RS232 for control and setup – which is now possible using the Meridian setup
64 Can I use 562V.2 with a CD Recorder?
Yes, 562V.2 can be used to direct analogue or digital sources to a CD Recorder.
65 Can I use 562V.2 with DSP speakers?
Yes, in fact one of the uses for 562V.2 is to bring analogue sources together for a pair of
Meridian DSP loudspeakers.
66 Can 562V.2 play LP?
Yes, you can fit an optional phono module and enjoy your LPs on the system.
568 with 562V.2…?
67 How many audio inputs do I get with this system?
You can connect 7 digital sources to 562V.2 and a further 5 to the 568, so all 12 sources (on
the MSR) can be digital. In addition, you can connect 7 analogue sources to the 562V.2 and a
8 to the 568. I think the answer is ‘plenty’!
68 Should I make both analogue and digital connections between 562V.2 and 568?
Yes, we recommend it. Obviously we want as many sources as possible to reach 568 in the
original digital form. For analogue it is better to select those sources in 562V.2, but to do
analogue to digital conversion in the 568. This reduces jitter on the analogue sources.
69 I have a Meridian 562/V. Does it need an upgrade to work with 568?
No it doesn’t. Your 562/V will work just fine. However, may be interested in getting a software
update for it so that you can configure the system using the Meridian Setup Application. (See
Q. 72).
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
70 Do I need to use a computer to set up a 568?
No, it isn’t necessary, but it is usually easier.
568 comes with a number of built-in Types (factory-preset standard setup combinations – see
Q. 74) which cover most speaker combinations.
For more advanced setup of the many audio options, computer setup provides a quick and
easy way to complete the system setup. You can also review settings, store and print the
setup and build User Types (see Q. 75).
The setup program runs in Windows™ 95, 98, 2000 or NT.
71 What about Calibration?
The first time the surround installation is put together it should be calibrated – and your
Meridian dealer will be happy to do this for you. 568 has a number of sophisticated setup
parameters and provides a series of special test signals and sine-sweep that allow you to get
the best sound.
The Calibration routines allow you to adjust delays for speaker distances, to adjust phase,
level and image integration.
Best of all, when the calibration is done you can load the settings back into your PC so you
can keep a backup.
72 I really wish I could use a computer to set up a 562V.2.
Well now you can. Version 2 EPROM for the 562 family adds the ability to configure 562V.2
using the Meridian Setup Application on a Windows PC.
The 562V.2 does not have Flash memory, so software updates do require an EPROM
change, but this kind of product typically has needed very few updates. This also means that
the 562 will not store User Types (see Q. 75).
You can still configure the 562V.2 from the front panel, but most people will appreciate the
superior interface of the computer and especially the ability to save and restore setups.
73 Can I upgrade my 562 or 562V?
Great news: a version 2.0 EPROM can be fitted to any existing 562 or 562V – inexpensively
adding PC setup to products that are up to six years old.
The new video features in 562V.2 are not available as an upgrade.
74 What is a Type?
A ‘Type’ is the Meridian term for a complete suite of settings for a product. When a product is
‘Typed’, all the user-configurable settings are reset to one of a number of factory-preset
Types. In 568, examples of Types may be ‘all the settings for an analogue THX speaker
system’, etc.
75 What is a User Type?
Like other Flash-memory-based Meridian products, 568 supports User Types. A User Type is
built in the PC setup application. For example when you have got the setup just right for your
568 you can save it as a User Type and give it a helpful name. This User Type can then be
stored in the 568.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
Why would you do that? In case someone overwrites a setting or makes an adjustment you
don’t like you can restore the whole item by restoring the User Type – even if you are
nowhere near a PC. (You can also lock menu settings to prevent such accidental
You may want more than one User Type. For example, if you occasionally move the 568
between systems with different requirements, or if you have a few very different applications
for 568 they can all be pre-programmed and stored in its flash memory using a PC. Then
switching between applications takes less than a minute.
76 How is the software changed?
568’s software can be updated using a computer with an RS232 connection. Updates will be
posted from time to time on the Meridian web site at:
77 Can I control it with AMX, Crestron or Phast?
Yes. The 568 has a full set of commands that allow it to be fully integrated into any control
system that uses an RS232 bridge.
About upgrades…?
78 What is the upgrade path for 568?
None of us can know what the future will bring. So before looking forward I would like to
explain our approach to upgrades by describing what we did for the 565, the 568’s immediate
predecessor and market leader for five years.
It is astonishing how rapidly things have changed over the lifetime of 565. For example, when
this first true-digital surround processor was launched (with an architecture that would support
upgrades) things like Dolby Digital, DTS, MPEG audio, MLP and DVD did not exist. Yet, not
only were we able to offer a total of 6 major software upgrades but two DSP processor
upgrades that allowed the 565 not only to decode these formats, but actually to be the first
and best processor on the market to offer decoding for each of these new formats.
In the 6 versions were innovations like Stereo Surrounds, variable crossovers, better
calibration, adding side speakers to a theatre, LipSync™ … the list is very long.
These upgrades were available for all 565s ever made enabling our customers to follow
changes in the marketplace and to continue to enjoy a world-class product.
This is a stunning record, unequalled by any other company.
So why do we want to introduce 568 and not keep upgrading 565? Not every upgrade that is
desirable is economical. When 565 came out there was no hint that we would see sample
rates running up to 96kHz. Even if there had been a hint there was no interface and certainly
no DACs able to operate with state-of-the-art sound quality at either 96kHz or 24-bit. In the
intervening time Laserdisc came and went as the dominant movie carrier. DVD was unheard
of and now it is evolving at a breathtaking rate. Eventually DVD will bring discrete
multichannel, complex connection interfaces and copy-protection systems that effectively
mean we would, over time, have to replace nearly every component in a 565 to keep it
current! That just isn’t fair to 565 owners. An upgrade path should not involve buying the
product twice over.
By contrast the Meridian 861 Reference Surround Controller has been designed using highperformance motherboards in such a way that all the circuitry is on plug-in cards. This means
November 1999
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
everything can be upgraded, changed, evolved and so on. It is a great performer but it is in a
very different price range.
The 568 takes as much from 861 as is practical and extends the 565 concept by adding a
multichannel digital input expansion port and room for changing and adding to the DSP
processors. We think we have made a state-of-the-art machine that should lead the field for at
least five years and, like all Meridian products, it is designed to give wonderful sound for a
One word of caution: technology never stands still. Meridian is likely to evolve 568 and
associated products in sensible ways that improve the sound, picture or versatility. This does
not mean that we will do everything, or that we will do it first – so you must be happy with
what you buy today. However whatever we do will be excellent, for good reason and carefully
thought out.
Ask your dealer for a copy of our white paper on upgrades, ‘Bulletin on new technologies,
product roadmaps and upgrades’.
79 Will the 568 be upgradable to DVD-Audio?
It’s very likely. This is a very exciting time for Meridian and no other company is better placed
to make the most of DVD-Audio when eventually this settles into a full specification. The 568s
architecture is perfect for getting the best from discrete multichannel, as we ably demonstrate
now with Dolby Digital, MPEG, DTS and MLP.
In Question 52 I explained about discrete multichannel inputs (which DVD-Audio will need).
There is a lot to be solved in the area of copy protection, so we won’t make any outrageous
promises. However, we hope to have convinced you that we have designed 568 for flexibility,
with ingenuity. Watch this space…. We will update this answer as progress is made.
I know you don’t want to make firm promises, but can you indicate the sort of things
we might see in future 568 upgrades?
Obviously we are looking for a sensible way to integrate DVD-Audio and other highperformance audio formats into the Meridian Digital Theatre components. This has been
uppermost in our minds as we designed 568.
I don’t forsee a lot of changes in movie formats any time soon. Obviously there are niceties
like EX, but the real expansion and upgrade for 568 may well be in areas of speaker
interaction, speaker control and DSP for things like DVD-Audio or room correction.
More …?
81 Where can I learn more about 568 and 562V.2?
You should talk to your Meridian dealer. You can also get more information from our website:
An current version of this FAQ:
568 and 562V.2 user manuals:
568 and 562V.2 PC setup application:
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
Inside 568 …?
82 What’s inside a 568?
8 Analogue Outputs
Analogue and Digital Inputs
and ADC
PCM or AC-3
S or composite Video
Video OSD
Bypass Output
8 Digital Outputs
Inside the 568
S or composite Video
The 568 can accept up to 7 sources. These can be digital (cable or optical) or
MHR supported on inputs.
The Input selection is fed to the main processing and the bypass output.
568 will decode the input appropriately for the incoming format and onto the
configured loudspeaker array. MHR and/or double-speed may be used on digital
There are 8 analogue and 8 digital outputs.
MHR supported on outputs.
There is a studio-grade video loop-through that adds OSD to either composite or S
video signals (but not both together).
Expansion slot for future high-rate, multichannel and/or protected digital inputs.
DSP processors on exchangeable cards.
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Bob Stuart answers Questions on Meridian’s 568 and 562V.2
High-precision proprietary DSP is used to upsample PCM (e.g. from 44.1kHz or
48kHz to 88.2kHz or 96kHz) with 24-bit precision if requested by the user.
High-precision proprietary DSP is used to downsample PCM (like 96kHz to 48kHz)
with 24-bit output precision for certain surround modes.
Surround decoding (Dolby Digital, DTS, MPEG, MLP etc.)
Format upscaling (Music, Trifield, ProLogic etc.)
Speaker Layout management
Speaker crossovers
Bass management and protection
Calibration sounds
Differential and global audio delays
Phantom Sources
The same physical input can be selected using more than one Source key to create a
‘phantom source’, so that 568 automatically loads a different combination of
processing settings.
Hardware details
Advanced PCB techniques. Extensive use of 4 and 6-layer PCBs.
10 re-programmable logic devices for flexible data handling and control.
Expansion port for future digital input and output interfaces.
Supports 5 DSP processors, 4 on plug-in cards.
Flash memory for software updates.
Very advanced analogue circuitry. Uses highest quality audiophile-grade
Fan kit option for difficult built-in situations.
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