Mini-Boosters

Here are some variations on the JFET Mu amp booster made famous by Jack Orman at amzfx. We call it Jack of all Mini-Boosters, mostly as a tribute to Mr. Orman, but also this circuit board will accommodate many variations.  We have shortened the name to the acronym JOAM in some cases.

AMZ Mini-Booster

This is the one that started it all. Jack took the rough design of this JFET Mu amp from an ancient National Semiconductor App note (see bottom of page 5) and refined it into this wonderful booster for guitar. There is lots more information available about this booster at
amzfx Lab Notebook.

Boutique Boost

This is similar to the first version of the Fat Booster. It has the input Gain control and a tone control added to the design.

Common File For AMZ Mini-Booster and Boutique Boost


Would you like a Ready to Solder Circuit Board for this project?