[2481] Amp In A Box

Date: December 19th, 2018 | Comments : [1] | Categories: DIY.

The concept of a pedal that sounds like an overdriven amplifier has been around a long time, and in the late 1990s, I contributed to the field with several designs. The most influential of them has to be the Booster 2.5 pedal, which was a derivative of my earlier Mini-Tubes Preamp.

The Mini-Tubes was 4 gain stages but several players who tried it remarked that the gain was over the top, so I then cut it down to 2 gain stages. Finally, Aron Nelson revised some values in my basic two-booster design (Booster 2) and the Booster 2.5 was born. It served as a starting point for many similar amp-like pedals that were to follow.

Among the numerous DiY derivatives of the dual mini-booster that were contributed to the forums around that time include the Sweet Thing, BSIAB and BSIAB 2.

Click on the names of the pedals above to see their schematics.

Variations of these DiY designs found their way into a variety of commercial amp-in-a-box pedals that came along in the following years.

The dual mini-booster designs were not my first amp-like pedals, since more than 10 years before, I has created the Fet Muff, which has 4 jfet common source stages in series voiced like a classic Bassman amplifier. This method of cascading simple jfet amplifers to make amp simulators has also found its way into many commercial designs and still sounds really nice for lower gain pedals.

Also, if you want to see some archived history of this, read about it in the First Stompbox forum that later became DIYstompboxes. Try this link first, but there are lots of others in that archive, though you may have to be logged in to read them.


One Response to “Amp In A Box”

[786119] admin Says: 1:50 pm, December 20th, 2018

I had never heard the term “foundation overdrive” until recently and someone sent me an email about it.


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