viva Analog “Arbutus Boost” // jcm(c)2012

Dynamic MOJO under your fingertips …

A step in the right direction as a booster pedal, this time using a soft switching approach to opto-controlling the gain level in my original (non-linear) “Triode emulating” booster design … unlike my previous true-bypass builds which are naturally prone to switch “popping” – the drawback of producing a Non-Linear output!

Briefly, this circuit replicates the large-scale non-linearity of a vacuum Triode voltage gain circuit, the same kind used in vintage tube circuits (Fender, Marshall, …) It is *very* good at waking up old low-gain vintage tube amps, and some users report having the pedal on all the time as it takes a very natural seat in the gain structure of an amplifier chain …

The switcher allows going between unity gain and variable output, capable of delivering considerable boost levels (x11 or more), with added pick “edge” sharpness and squeaks …

This version is a design especially made for Arbutus Music in Nanaimo, BC …

the idea has been licensed and incorporated into alternate hybrid designs … these two guys run a studio in London and have adapted my idea a little further :

thank you for introducing me to your booster. It’s completely changed how I record guitars =)

I think the best recording example I have is this:

All guitars were tracked with your non-linear booster, last in chain before the amp.

A laidback live version if you wanna hear it on it’s own (with a funky fuzz):

… the concept is also at play in my battery/solar-powered “tube emulating” SS amplifier: the ATAK60 !!

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