Part of the last request included a cab simulator to run the headphone amp through. The ROG Condor is a great cab sim and has a fairly low parts count. It uses a JFET amplifier at the input, boosting the signal to drive the following 3 filters (Bridged-T notch filter, High-pass filter, and Low-pass filter). Much more info on the circuit can be found here, as well as a few mods. J201 apparently sounds the best for Q1, but similar DSG pinout JFETs will also work. Any dual opamps can be used for the 2 ICs, so socket and try the usual candidates (TL072, JRC4558, etc).
