Meridian Audio 861V4, 861V3.5, 568V2.5 User Manual

Technical Information

JMB v 1.0 – 8th Dec 2003

V4 Presets and Usage

Introduction.
This document is intended as an introduction to the style of DSP Presets in 861v4, G68 & 568v2.5 -

primarily for customers who are already familiar with earlier Meridian processors such as the 561 or earlier
versions of 568 and 861.

861v4, 861v3.5, 568v2.5 and G68 share the same decoder modes and DSP presets. This is at the point in
time where they incorporate THX UltraII Cinema and Dolby PLIIx.

Basic Preset structure - why have we changed it?
In older products a Preset was linked directly to a type of audio stream. E.g. “Digital” was a Preset for

Dolby Digital multichannel streams only, “Dig THX” added THX extensions to the basic Dolby Digital
mode.

Adding extra processing modes, such as Dolby PLII and THX Surround EX, was beginning to make the
range of options quite complicated - particularly in the GUI, where the user is presented with all of the
possible options at once.

For these reasons the processing performed in Version4 is split into two parts, the decoder and the mode.
The mode is what the user sees as a ‘Preset’, the decoder is automatic and does not require any settings
or adjustment.

This presents a uniform set of options, based on how many channels of audio are actually on the source
medium.

Discrete

Cinema

Dolby Digital 5.1

DTS 5.1

MPEG 5.1

Multichannel PCM

Multichannel analogue

Dolby Digital 2.0

DTS 2.0

MPEG 2.0

2-channel PCM

2-channel analogue

Decoder

Decoder Speakers

THX
PLIIx Mov6
PLIIx Mus6

THX EX
THX UltraII
THX Music

Direct
Music

Trifield

Ambisonics

Super Stereo

Music Logic

Mono

TV Logic
PLIIx Music
PLIIx Movie

PLIIx THX

Speakers

The decoder mechanism.
The processors automatically select the decoder based on whatever stream is coming in, be it Dolby

Digital, DTS, MPEG or PCM. The stream display exists in the same form as previous processors. E.g.

“DVD AC3 3/2.1 48k”

In this case the decoder part of the product will pass 6 channels of decoded audio to the surround
processing section. The user is then presented with a range of Preset options for 6-channel audio.

Meridian Audio Limited, Stonehill, Stukeley Meadows, Huntingdon, Cambs PE29 6EX

Tel [phone] Fax [phone]

http://www.meridian-audio.com/

Technical Information

JMB v 1.0 – 8th Dec 2003

Similarly, if a DTS stream was presented on the input, the display shows:

“DVD DTS 3/2.1 48k”

But the user has the same choice of Presets as above.
If the processor is connected to an 800 or G98 (in a standard setup, where the player is decoding the

audio stream) then the stream display will show something like:

“DVD PCM Movie6 48k”

The user is presented with the same set of 6-channel Presets, even though the decoding has been
performed elsewhere.

If the decoder only detects two channels of audio then the range of Presets available will change to the
two-channel set, which includes many familiar modes like “Trifield” and “TV Logic”. Note that this also
applies for encoded two-channel streams, where the stream display would show, for example:

“DVD AC3 2/0.0 48k”

Digital inputs - Smart Link.
861v3 and 800v3 introduced the Smart Link protocol, whereby the player indicates to the processor how

many channels of audio are on the disc it is playing, and what the original format is. This allows the user
to set different Presets based on the type of disc in the player, e.g. “Trifield” for CD’s (2-channel music),
“PLII Movie” for Dolby Digital 2.0 (2-channel movie), “Discrete” for DVD-A (6-channel music) and “THX” for
Dolby Digital 5.1 (6-channel movie).

The processor can apply the same rules to formats it decodes itself, and use the same four default
Presets that Smart Link uses. This removes the need for an “enhanced” source to accept a multichannel
input, and presents a consistent range of options to the user.

So, all digital inputs have four default Preset settings, one each for:

•

Music2

•

Movie2

•

Music6

• Movie6

Analogue inputs.
Analogue inputs have no way of distinguishing source material, so they default to assuming ‘Music’. The

default Preset for Multichannel analogue inputs is stored in the ‘Music6’ slot; 2-channel inputs use the
‘Music2’ slot.

Available presets.
Not all presets are available all the time, with the aim of improving the clarity of the user interface. This

section describes those special cases.
Ambisonics (UHJ & B format) and SuperStereo are only available if there are two or more surround

speakers.
‘PLIIx Music’, ‘PLIIx THX’ and ‘PLIIx Movie’ revert to PLII variants if there aren’t four surrounds.
Ambisonics (B format) is only available if the decoder says Music6. This is because Ambisonics would

normally only arrive from a multichannel analogue input or a (decoded) DVDA, it can’t be encoded with
lossy compression like AC3 or DTS, so would not be a sensible Preset to use if the decoder said Movie6.

Multichannel presets that need four surrounds (THX UltraII Cinema, PLIIxMus6, PLIIxMov6, THX
Surround EX) are not presented as options in the GUI or available from the front panel unless four
surrounds are defined.

Meridian Audio Limited, Stonehill, Stukeley Meadows, Huntingdon, Cambs PE29 6EX

Tel [phone] Fax [phone]

http://www.meridian-audio.com/