"The SKRM-C8 reverb and effects module line is an easy to integrate effects solution for your pedal, amp or other audio equipment. These modules are available pre-programmed and can be custom programmed for your product. Modules operate from 5V to 12V DC to ease integration into your design." - quote from the Experimental Noize site.
The SKRM-C8 like all of its sister modules has an EEPROM that can be easily reprogrammed with any DSP algorithm written for the FV-1 chip. There is a community of users and DSP writers that have created numerous algorithms for these modules and I have taken several to include in various projects in the past. My Therematron uses one of these modules for its effects.
The Warlord uses patches from SKRM-C8-eTap2 which was a project of has specific patches which emulate vintage tape echo machines and more as used by guitars like Hank B. Marvin of The Shadows.
So the main differences between the UM-XN1 and the Warlord are:-
1. Much sturdier case which includes foot switches for control of the effects.
2. LCD where custom patches can be stored and retrieved
3. Hi Gain stage for direct input from a guitar pickup
4. An Arduino Pro Mini is used to control the FV-1 chip and to store patches
5. It's orange !
This unit runs off an external dual 9v power supply.
What I gained from this project was some skills in spray painting cast aluminium cases to a point where the coating is very robust using quality spray paints from the Rust-Oleum brand.
Alas, the Echotapper project no longer exists but the wonderful designers over at Stanley Effects has created the Blue Nebula pedal which is based on the Echo tapper.