An original UniVibe is, more or less, a phaser pedal. However, it uses discrete transistors instead of the opamps that later models used, mainly because it was difficult to get everything just right so that it sounded great. The preamp of the UniVibe could accept two inputs, then amplified the signal and passed it to one of the first three phase stages. These stages are all identical and simply prepare the signal for the last phase stage. Here, it’s phase shifted and sent to the output mixer. This mixer adds the chorus signal and adjusts the phase delayed signal for output.

The signal then hit the LFO and Lamp Driver if the player wanted a slow speed effect. Some of the clones, like the JAM Pedals one mentioned above, use original transistors and other components to faithfully recreate the sounds of a vintage UniVibe. Many come close, but nothing matches the original!