Appendix D: Hdmi Handshaking - Bryston SP3 Owner's Manual

APPENDIX D
SP3_Notes_HDMI-2_20120111
(11-Jan-2012, Stan B ., Bryston Ltd .)
HDMI Handshaking
When SP3 selects HDMI input port as its audio signal source, it acts as an HDMI repeater, placed in
between HDMI signal source (DVD player, BD player etc) and HDMI signal "sink" (TV screen, TV
projector etc). Every class of the devices on the HDMI chain has to respond to the HDMI handshake
procedure, initiated by the signal source, that is by a player.
power up, on disk reinsertions, or on other events. In order to make the initial handshake proceed
optimally, the HDMI devices should preferably be powered up beginning with the "sink" (TV screen),
then the repeater (SP3) then the player. That way the main signal source will be immediately able to
poll (handshake) the rest of the HDMI chain which will already be powered up and ready to respond.
Using more than 1 HDMI source (player)
If 2 HDMI sources are connected to SP3 HDMI inputs, then SP3 will select only one link at a time,
leaving the other link "dead ended". This may break the established handshake status between the
player that is not currently active, and the TV screen resulting in a possible change of the player output
signal format. This behaviour is strongly player-dependent and copy-protection dependent on the
media being played. Some DVD or BD players maintain the last signal sample rate and format that
was played previously to an interruption (or disconnect)
downgrade the output stream from multi-channel audio to stereo or from encoded streams such as DTS
or Dolby Digital to PCM. Some players may also downgrade the sample rate of audio and downgrade
the video resolution.
This may cause various artefacts or somewhat unpredictable behaviour (loss of audio etc) when
switching away from one HDMI source to another source and then back. If the drive switched the
format while being disconnected and would not restore the previous one, then pressing HDMI button
again to switch it off to analog
original.
If that does not restore the correct HDMI status then reinserting the disk or re-powering the player
may be necessary.
HDMI multi-channel or two-channel
The signal source determines the channel format. If the number of channel is not as expected, for
example 2 instead of 5.1 or 7.1 then the player may have to re-handshake the communication channel
through HDMI in order to recover the proper status. Certain media revert to a 2 channel audio format
during menus and then switch to multi-channel when playing a selected contents. Some media
contents may be originally recorded as 2 audio channels, in this case one can use the surround
3
synthesis feature in SP3 to produce 7.1
1
As long as the disk is in.
2
HDMI button toggles between HDMI active and Analog mode, while the actual HDMI chain link from the source to the
TV screen remains unbroken. As long as the main source selection remains unchanged. This feature allows passing the
video signal through HDMI while using analog for audio. At the same time since the HDMI chain remains unbroken while
toggling the HDMI active on/off , it allows the player to re-handshake with the TV screen re-establishing the original
channel format.
3
This is often referred to under the term "re-creation" mode that is creating the extra audio channels out of the stereo feed.
Use surround left and right arrow keys to select among several surround modes. Those selections are not applicable when
the original content is 7.1, and only a limited selection is applicable with the original 5.1 stream when 7.1 has to be
synthesized out of the 5.1.
2
and then on again may force the drive to re-handshake and restore the
HDMI Notes
SP3 PREAMP / PROCESSOR
HDMI HANDSHAKING
The handshake is initiated normally on
1
, some other players tend to immediately
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