On the functionality of the "Master Volume" and "Expression" Faders in Synchron Player
CONCLUSION
1. Users can treat "Master Volume" and "Expression" faders interchangeably as if simply "Output Vol. X" and "Output Vol. Y". Other than in the case described in 6.1 below, there is no technical or practical necessity for staying with their factory-default roles and CC assignments, in controlling Synchron Player's audio output level.
2. These two faders are logarithmic attenuators; both have practically the same scale and operate post-Fx.
3. There is no technical necessity for users to take into account the order of precedence of these two faders in the audio path; there is no intrinsic theoretical or practical advantage to be had either way around.
4. In effect, the sum of their individual dB attenuations is added to the dB output levels of all internal mic channels and aux channels in parallel. This functionality holds true regardless of however those mic and aux channels may be individually routed out to separate audio streams in the Synchron Player's host. There is no technical necessity for users to take into account the arithmetic processes used by the underlying software in achieving this functionality.
5. Their individual CC value settings of course cannot directly provide accurate indication of their dB attenuation, and hence may lead to difficulties when the user is dealing with dB values (e.g. when adjusting working headroom in one instrument, or adjusting the gain-staging across the whole project).
6.1 If choosing to preserve the factory-default 'inherent balance' between all Synchron Player instruments, then all Synchron Player Master Volume faders in the project can simply be left untouched at their factory settings. (Alternatively, if desired, each of these factory-default relative settings - as CCval or dB as appropriate - may be transferred to other level adjustment devices located elsewhere in the project, thus freeing the Master Volume fader from this role.).
6.2 If the other, 'working' fader is required for mixing and thus is to be initialised at an attenuation point substantially below 0 dB attenuation (e.g., somewhere in the range of -6dB to -10dB) in order to provide working headroom, then of course this initial attenuation point - which can be regarded as if the "zero level" on any typical mixing board - should have the same value (in dB or CCval) in all VSL instruments in the project, to preserve the factory-default inherent balance overall.
6.3 If the configuration described in 5.2 is in use, and if subsequently in any particular Synchron Player it becomes necessary to set the working fader's initial point even lower in order to provide extra headroom, then by also adding that extra amount (in dB) to the 'inherent-level' fader in that instrument only, the factory-default balance overall will be preserved. This of course depends on there being enough room to add the extra headroom dB amount to the 'inherent-level' fader in this instrument; if not, the extra headroom can be added by means of some other level-trimming device affecting only the instrument being altered (e.g. the Gain control in the Power Pan plugin in the Synchron Player's internal mixer.)
7. For cases where these two faders are not remotely controlled by automation that indicates reasonably accurate dB amounts at source, there is clearly a dire need for instant indication - within the Synchron Player itself - of the attenuation dB amount being applied by each of these faders.
Notes:-
(i) An earlier edition of this conclusion was previously posted in a thread that has now been re-titled as "Further Considerations on Volume/Expression", and in which that previous conclusion has since been deleted.
(ii) Any further exploration or elaboration of the theoretical and practical bases from which this conclusion here was drawn are outside the scope of this thread; they belong in the earlier threads that address those topics, or in new threads.
(iii) Please let's be considerate to future readers who may want direct, reliable facts and answers without having to trawl through pages and pages of discussions spread across several threads (and which might still be littered with technical myths or otherwise incorrect, incoherent, misleading or irrelevant information - as is so often the case in Internet forum discussions).
(iv) Relevant threads from which - to various extents - this conclusion was drawn are: [TBA]