The Experiment resumes .....

Written by Steve Poskitt

After a long time with no input finally decided to revisit the blog and continue with the quest!

Thanks to the Guitarix team there has been a major update to some of the tools used to simulate circuits using the DK method.

What were once experimental tools and used to generate filters to simulate the linear parts of a circuit have been expanded by brummer to enable simulation of the non-linear elements in a circuit ( by far the most important in guitar amplifiers and effects ! ).

Read more: The Experiment resumes.....

Chumps Big Brother

Written by steve

So far so good with the simple valve amplifiers.

All the models so far are single ended designs, in which one single valve powers the output transformer, but most guitar amplifiers are push-pull designs, where a pair of valves ( or more ) drive the transformer.

This type of design is more complex and involves splitting the signal into positive and negative halves of the wave form ( phase-splitter ), amplifying both halves separately and then recombining by using them to drive an output transformer with 2 equal windings. This comes with a new set of problems and possible distortions.

Read more: Chumps Big Brother


Written by steve

As The Chump sounded so good decided to insert the tremelo circuit into the amp to clone Fenders later VibroChamp model, and again seems to work pretty well.


Read more: VibroChump

Birth of a Chump

Written by steve

Having been pleased with the results so far it was time to try and build a complete guitar amplifier. To keep it as simple as possible the design is again loosely based on the Fender Champ, very simple in design, 2 stages of preamp valves and one power valve.

12AX7 --> Volume --> 12AX7 --> 6V6 --> 1x 8 speaker

Read more: Birth of a Chump

Studio Preamp

Written by steve

Next a preamp based on the legendary F2-B studio preamp from Alembic. is used in many studios for direct injected bass in particular.

The circuit is almost exactly same as that used in many tweed Fender amplifiers.

Read more: Studio Preamp

Pedals galore.

Written by steve

Having been satisfied with the previous experiments with a simple 2 stage valve preamp wrapped around the tilttone control and resonance/presence feedback loops I thought it would be interesting to hear what it had to do with several other effects. Using the models already available in the Guitarix source I went into mass production!

Read more: Pedals galore.