The Lamington Junior – an easy to build great sounding 2W valve guitar amplifier

A kit of all parts, and a construction manual for the Lamington Junior are now available!

Introduction  I   Design   I   Construction

Here is a design for a great sounding simple, easy to build 2W amplifier. It was developed with the beginner to amp building in mind. It is powered by a 12V AC plugpack to eliminate contact with the 240V mains making it a safer amp to build for a newcomer to amp construction.

You may think that 2W  is not much amplifier power, however this amp can certainly make a lot of noise with a surprising amount of clean volume. It is an ideal amp for a bedroom or for recording.

The design for this amp took quite some time in development – the design brief was for a lower power amp that reproduced the warm, chimey cleans of the original Lamington amp, while still providing a great overdrive tone. This is a challenge for a low power amp. In developing this amp design, I experimented with numbers of amp configurations – single ended, push-pull, triode and pentode preamps, various tone stacks, valves etc. Some configurations produced a gnarly overdrive but lacked the clean tone that I wanted.

I am very happy with the final result – an amp that is straightforward for a first build and with a great tone for a bedroom or a recording amp. The clean tone has the same “sparkle” and warmth of the Lamington amp with a surprising amount of clean headroom. Advance the volume to maximum, and the amp has a very nice crunchy overdrive tone. Used with an outboard drive pedal, the amp really screams with that characteristic “power stage grind”.