I recall a friend of mine in The Service playing with a Power Soak on his master-vol Marshall back in the early 80's - sounded great into a 4x12.
I have a Power Soak that I bought to tame a Mesa Mark IIB but never really liked how it changed the amp's "feel" - sold the amp as it was just too loud. I did love it, tho', and now have a .50 Cal. I like ever so much more.
I still have the soak, also, but I now live inna house and so it's not been necessary.
Shortly thereafter, well, late '80's, the Jubilees and then the 900 series came out and they sound good between increasing the amount of pre distortion with the pre tubes and FET's. Not an 800 sound, or a master volume, of course (tho' not far off), but they became a standard. I've been considering the later DSL's for a while but bought a HRDX instead as I have a Jubilee.
There are AIAB pedals that claim to go after specific Marshall sounds, ex., the DLS, the Exotic SP (switchable, even), the Plexion and others. Lots of others. One Control has one that's supposed to sound like a Jubilee; Lovepedal, also. IME, such pedals do sound Marshall-ish, but not really model-specific.
The One-Control Super Apricot is supposed to sound like a tweed or a Supro (contradiction?), whereas the Blue Twanger is supposed to be like a small Fender tweed to black to silver face (where's the brownface?
) ...
I don't really hear 'em as distinctly emulating a specific model, but a general area of ampage, and I do like' em.
The cab pedals are hugely useful in terms of making differentiated sounds. I have a Microcab that has 1x12 and 2x12 and 4x12 settings some of what it calls vintage. I have a Shaper pedal and the stereo Digitech VRdry and they have adjustable presets, as well. The DSM Omnicab Mini is a little different in approach but you can make a AIMB sound like a combo or a stack, in comparison to another AIMB track, pretty easily with all of 'em.
For me, the key thing is mostly what's going on in the upper mids with these AIAB pedals, that can then be further addressed with the cab sims.
I love this stuff!