7 things to know about London Drive
- London Drive is a simple but pleasing distortion circuit and a good way to learn soldering.
- The circuit is based on the external input and mic pre-amp circuit from the EMS VCS-3, the classic British synth, designed at the EMS studios at 49 Deodar Road, Putney. The same circuit was used in the Synthi-A briefcase.
- London Drive is obviously very similar to Mini Drive, which is based on the input circuit from a MiniMoog. It has the same two-in two-out layout to make it easy to patch feedback loops.
- Does London Drive sound different from Mini Drive? I think so. To me, Mini Drive has an interesting saggy(?) quality, it reacts strangely to big gain changes, and is very mid-rangey. London drive is clearer, faster(?), brighter, more bass, more treble.
- It's a simple discrete circuit: three transistors for the audio, three more to drive the incandescent overdrive bulb. The VCS-3 didn't have a level indicator, so it's just the Moog circuit here. Along with modern transistors, there are also a few minor changes to the VCS-3 circuit to make it work in this context, so purists should look away.
- To make feedback patching easier, the bottom output is inverted, the top output isn't. Inversion is done by a very basic transistor phase splitter circuit, so the outputs aren't identical (DivKid explains this in his video below).
- Check the Mini Drive documentation and videos for patch ideas and feedback tips.
DivKid's brilliant Distortion Masterclass