Amplex is a multiamp sim plugin. You can load a variety of different amps into it using txt files. It sounds crazy but it's simple, easy to use and sounds pretty damn good. I'm excited to see where this goes in the future because I think it's a game changer for free amp sims. The list of amps already available is extensive including 5150, Engl and SLO inspired presets. Amplex: The IRs I used for the demo:
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