Re: Marshall Origin Heads
I gig regularly with a 20H into either a 2X12 with Greenbacks or a 4X12 with WGS Invaders. As was previously said, it sits kind of between an 800 and a plexi gain-wise when you can turn it up. If you can't turn it up, it has very little gain (like a plexi).
My 20 watter is more than enough, even with our loud drummer. In fact, I use a Bad Cat Unleash 2 to bring the volume down to reasonable levels. If I didn't use an attenuator, I wouldn't be able to turn the amp up past 3 live. I use gain 100% of the time and roll back my guitar volume for cleaner sounds so any perceived lack of headroom from a 20 watter is not a problem for me.
I've owned approximately 15 real Marshalls in my life, from a '68 JTM50 all the way through a DSL100 and almost everything in between. My frustration was always with an inability to turn them up to get the goods. (This was prior to getting the Unleash). I'd always have to resort to using drive pedals, which to me, never sounded as good as the amp turned up. That's not a problem with the Origin. I've toyed with the idea of getting a Studio Vintage 20 but, considering I'm totally happy with my Origin, I don't think I need to spend that kind of money for the SV.
I replace all of the stock tubes with real, Made In Great Britain Mullard 12AX7's and old Siemens EL34's, which warmed the amp up a lot. I run Presence, Treble, and Mids on 10, Bass between 0 and 2, Tilt between 8 and 10, and Master and Gain on 8. With my Les Paul with Pearly Gates, I get really close to KISS Alive tone, which is what I'm going for.