Simple JFET Preamp for an iDevice Guitar Interface

iPad Guitar Interface Schematic

Following up on Part 1, it’s time now to get into the heart of the project:

In this video, I talk about how JFET’s work, then work up a circuit diagram (as shown at right).

Then, I prototype the circuit on the breadboard of my Radioshack Electronics Learning Lab Model 28-280, and finally play through the circuit to show how it sounds.

In Part 3, I’ll demonstrate how to assemble the circuit so that it fits entirely inside the jack.

Here are some useful resources and background reading:

Some articles on JFET preamps:

Tillman’s FET preamp using the J201:

Some relevant forum topics: