[LAU] placement.

Ok, this might be a bit of curly question, and as i don't know if this is possible, either valid or not. The subject is placement, and pertains to orchestral recording. (My own work composed within the box with linuxsampler, from midi in RG, and recorded in Ardour.) I'd like to place my instruments as close as possible to an orchestral setup, in terms of recorded sound. That is, once i've recorded, i'd like to use convolution and other tools to 'correctly' place instruments within the overall soundscape. example: With the listener sitting 10 metres back from the stage, and facing the conductor (central) my 1st violins are on the listener's left. Those first violins occupy a portion of the overall soundscape from a point approximately 2 metres to the left of the conductor, to an outside left position, approximately 10 metres from the conductor, and with 8 desks (2 players per desk) about 4 metres deep at the section's deepest point, in the shape of a wedge, more or less. That's the pan width of the section. Now as i understand it, a metre represents approximately 3ms, so calculating the leading edge of the section across the stage as 'zero', the first violin players the furthest in depth from the front of the stage, should, in theory, (and i know this is approximate only, as i sat as a player in orchestras for some years, and understand the instinctive timing compensation that goes on) play about 12ms later than those at the front. Using the ears, and experimenting, this actually translates as about 6ms, before the sound becomes unrealistic, using layered violin samples, both small section and solo. (highly subjective i know, but i only have my own experience as a player and composer to fall back on here.) A violin has it's own unique characteristics in distribution of sound emanating from the instrument. The player sits facing the conductor, and the bulk of the overall sound goes up, at an angle, at more or less 30degrees towards the ceiling to a 'point' equivalent to almost directly over the listener's right shoulder. Naturally the listener 'hears' the direct sound most prominently, (both with ears, and the 'visual perception' he gains from listening with his eyes.) Secondly, the violin also sounds, to a lesser degree, downwards, and in varying proportions, in a reasonably 'spherical' sound creation model, with the possible exception of the sound hitting the player's body, and those in his immediate vicinity. (and other objects, like stands, sheet music, etc, all playing a part too.) I've experimented with this quite a bit, and the best result seems to come from a somewhat inadequate, but acceptable, computational model based on using, you guessed it, the orchestral experience ears. So i take one 'hall' impulse, and apply it to varying degrees, mixed with as precise a pan model as possible (and i use multiple desks to layer with,more or less, so there's a reasonably accurate depiction of a pan placed section, instead of the usual pan sample model of either shifting the section with a stereo pan, or the inadequate right channel down, left channel up method.) to make this more complicated (not by intent, i assure you), i'm attempting to add a degree of pseudo mike bleed, from my 1st violins, into the cellos sitting deeper on the stage, and in reduced amounts to the violas and second violins sitting on the other side of the digital stage. All of this is with the intent of getting as as lifelike a sound as possible from my digital orchestra. The questions: In terms of convolution, , can i 'split' a convolution impulse with some sort of software device, as to emulate the varying degrees of spherical sound from instruments as described above? So, one impulse (I use Jconv by default, as it does a great job, far better than most gui bloated offerings in the commercial world) that can be, by way of sends, and returns, be 'split' or manipulated not only in terms of length of impulse, but fed as 'panned' so as to put more impulse 'up', less impulse 'down' and just a twitch of impulse 'forward' of the player, with near enough to none on the sound going back into the player. I've written this rather clumsily, but i hope some of you experts may understand what i'm trying to achieve here. Can the impulse be split down it's middle, separating left from right, aurally speaking, and if this is possible, can i split the impulse into 'wedges' emulating that sphere i wrote of, more or less? if there's a way to do this, then i'm all ears, as my mike bleed experiments suffer from a 'generic' impulse per section affecting everything to the same degree, including the instruments bled in. I should note here, this is not about gain, but a wedge of impulse, cut out of the overall chunk, that represents a 'window' or pan section of the whole. This might seem somewhat pedantic in recording terms, but i'm trying to build a model, per 'hall' and create half a dozen templates to represent different size ensembles in different halls. So my small string section hall template might be a small church or performance room, like a library, or dancing hall. I would then only need to be creative with where i put my 'human' soloists, as emulators of slightly different interpretations of where note start and finish, velocity variation, etc....., and not have to reconstruct a convoluted model each time, for......my particular orchestra. (tongue firmly in cheek here.) Any help would be appreciated. I'm open to suggestions of placement convolution models, etc, but would prefer to use Jconv, as it works all day every day, and would be a constant across all templates. I suppose an analogy for the chunk of impulse idea would be to stretch a ribbon across a stage, and cut a metre out of the middle. That metre would be the bit i'd use, as a portion of the whole, in an aural soundscape, to manipulate, or place, instruments, to a finer degree, in the attempt to create a more realistic '3d' effect for the listener. That metre along with other cut out sections of the impulse soundscape could help me introduce a more....'human' element to a layered instrument section. I still rue the day orchestral sample devs decided to record sections at a time. This would have been so much easier if they'd recorded a number of desks for each section instead. Alex. p.s. I'm having a modest degree of success using Ardour sends, as a mike bleed template. Lot of work, and a lot of sends, but it's slowly coming together, and has reached the stage where i no longer think it's impossible.....