The Synthesis Technology E951 Looping Expander is an optional, add-on module that expands the functions of the E950 Circuit Bent VCO. The E951 requires an E950 to operate and is not designed to operate stand-alone.

Featuring a high-contrast OLED display, the E951 provides real-time information on the current operating mode of the attached E950 VCO. The display has a very wide viewing angle, making it ideal for both studio and stage performance.

The E951 adds the following enhancements to the E950 VCO:

- Displays the morphed VCO output wave
- Contains a full list of oll the words and phrases in the 9 speech banks
- Allows Short or Long vocal snippents to be looped and played
- Provides manual pushbuttons and external Gate/CV interface to Speak and Start/stop looping
- External CV with dedicated attenuator to change the Speech Bank on the E950