Orchestral reverb spacing

[Sam Spoons]

Me too (though acoustic jazz/folk bands rather than orchestras) but I think the OP is trying to construct a realistic sounding orchestra recording from samples/VSTi's.

[Drew Stephenson]

Percussion at back, long delay, strings at front short or no delay.

Assuming we're talking the delay on the reverb, nope.
Percussion at the back means that the sound has a short distance to travel before hitting the back wall and therefore the reflected sound arrives quicker than the reflected sound from the strings, which has a greater distance to travel (hence a longer pre-delay).

[Sam Spoons]

That makes sense

[Wonks]

That makes sense

Drew starts to doubt himself....

[Moroccomoose]

an MS pair or maybe spaced omnis - and add a bit of Bricasti dust on the stereo bus as required. A well placed coincident pair will always give a more realistic image with depth than any amount of hocus pocus in post... (just my humble opinion; carry on!)

Of course if you have a spare orchestra and room to play them in, the well placed coincident pair will do just perfectly... But this is really about trying to make virtual (sampled) instruments sound like they are in a real space and arranged realistically.

Stu.

[Drew Stephenson]

That makes sense

Drew starts to doubt himself....

Never stopped!

[Rich Hanson]

Percussion at back, long delay, strings at front short or no delay.

Assuming we're talking the delay on the reverb, nope.
Percussion at the back means that the sound has a short distance to travel before hitting the back wall and therefore the reflected sound arrives quicker than the reflected sound from the strings, which has a greater distance to travel (hence a longer pre-delay).

Of course, for the full effect you also need to account for the wall behind the audience too and the delay situation would be more or less opposite but possibly at a lower level (yes, I know that's probably over-complicating it)

[jimjazzdad]

Of course if you have a spare orchestra and room to play them in, the well placed coincident pair will do just perfectly... But this is really about trying to make virtual (sampled) instruments sound like they are in a real space and arranged realistically.

Stu.

Sorry. I must have been asleep in mastering class when they handed out the assignment.

[ManFromGlass]

Ok I finally had time to give it a try in Logic. First attempt set up correctly but didn’t really work for my ears until I put the sends all to pre-fader. Then I could lower the initial sound but keep the reverb high. Perhaps this is cheat way to lose the initial bright attack of instruments at the back, rather than eq them. I was only working with 1 short repeated piano note. I know strings, horns and other slower attack sounds may not need a pre-fader approach.
I’ll keep working with it.

The other issue is the one mentioned previously about how the further the reverb source is the more mono it is, or is it the instrument that becomes more mono? I better re-read!