2 Randall MTS RM4s in Jeff's rack (top of lower half)
The MTS (Modular Tube System) is, as the name implies, a modular pre-amp. Jeff has two RT4s, which are the rack-mountable model, with 4 modules each, likely dialed in with specific settings for different songs. Although hard to make out the individual modules, it looks like at least a couple of them are JTMs, emulating a classic Marshall JTM45 amp. He's also used the Tweed modules, which are based on the preamp of a 1959 Fender Bassman.
[product page | modules | wiki]
Jeff said the following about his 2011 amp rig (article):
I'm still using the Randall MTS modular system but now I'm using a set of custom modules made by Antonin Salva from the Czech Republic. The man is a total amp wizard. His company is called Salvation Mods (www.salvationmods.com). My Randall preamp has four channels:
Channel 1: Randall Tweed (this is the only standard module I'm using);
Channel 2: Salvation Mash-All (emulates four different Marshall amps- 59 Plexi, JCM 800, Jose Modded Marshall, and the JVM series);
Channel 3: Prototype of a custom module Antonin is making for me based on an Orange Rockerverb head. This is my main distortion sound. It sounds amazing;
Channel 4: Salvation Salvado. Module based on a Soldano head that I only use for leads.
Randall RT2/50 power amp into two Marshall 4x12 cabinets with Celestion Vintage 30s run in mono. I went back to using Marshall cabs for two reasons. One, the angle of the slant makes them much easier to hear on stage and also for the sound. Classic.