The Plate algorithm might be a good starting point, but it’s a little too metallic / artificial for my tastes (in this application). I recall reading that Sunset Sound’s Studio 1 live chamber was key. So a bright response, non-parallel walls, lots of early reflections … I’d go with a larger Room, or small Hall, as a base algorithm.
Most H9 / Space reverbs have some form of control over EQ control, so you’re not limited to any particular algo. Select the one that features the adjustments that you’re after. I like to play around with the early & late reflections in the Room algorithm, and take advantage of the programmed ‘realism’.
The Hall algorithm uses a different paradigm, but it can be tweaked for a similar result. Just remember that the major parameters [SIZE, DECAY, etc.] are all highly interactive with each other.
You’ll still have to pan it to the opposite side, adjust the MIX levels, achieve a “brown sound”, etc. BTW: the Sculpt algorithm is quite capable of recreating some of these classic rock guitar tones.
