William,
your intuition is intact! The cheapest Lexicon Digital Reverberator produces nicer reverberation then all of the plugins together, where Lexicons are not the only hardware processor which have a good reverberation sound. For orchestral, as well any other recorded music, the most important parameters are those for the early reflections. A Lexicon Digital Reverberator features parameters to program the important reflections, as well parameter to make the reverberation more real, for example:
Mid Reverb Time & Low Reverb Time:
this for example permits you to program a boomy gran cassa, and at the same time a shorter Mid decay.
Diffusion:
controls how initial echo density increases over time.
Attack:
high settings cause an explosive sound, while low settings cause the sound to build up slowly with time with distances, this all within the critical first 50 milliseconds, and programmable that a loud burst make the room sort of explode.
In Width:
for example 45° is a normal stereo reverberation effect, while 90° excludes any nono center signal from the reverberator.
Delay & Feedback:
for wall reflection, including feedback path
etc. etc.
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