Randall MTS Series Clean Module Modifications
Randall MTS Module Mods
One of the great things about the Randall MTS series is the ability to customize your tone to
exactly how you want. This includes modifying your modules to get the sound perfect for your
In this article we will cover the current modifications to the different clean modules. Check back often
as new mods are become available this article will be updated.
Randall Clean Mods
There was an issue discovered after several production runs in all the clean to mid-gain Randall
models including the Clean, Blackface, DLX, Top Boost, Plexi, JTM, & Brown, that causes excess
distortion overloading the input gain. Too eliminate this issue and clean up these modules,
position R1 which is a 470 ohm 1/2w resistor, needs to be changed to a 150 Ohm 1/2w resistor. This
is only the early production Randall models and some of the early Egnater models. The new modules
have been fixed at the factory but you should check any current module that you have. You can
identify what value is in your module by the color bands located on the resistor, 470 ohm
resistors have yellow, purple, and brown color bands, where the correct 150 ohm resistors have
brown, green, brown color bands.
Sound clip features a before and after on the JTM module with the resistor change. Overall impression
is that the module is less "buzzy" sounding.
The settings for the sound clips are available at Randall MTS