This has two booster in series in side. First is a NPN Range Master followed by a Sparkle Boost. The idea was Joe Gore’s. The two booster work well together. They each have their own flavor, and together get a good over driven sound.
The Range Master side sports a variable input cap. So this effect is a variable range boost, that goes from full range boost to treble boost. The other knob is gain.
The Sparkle Boost is a JFET boost by Andrew Carrol. This is a circuit that would make a good building block for a lot of projects. The First knob is gain the other is volume.
I built this over a year ago, and had originally omitted LED indicators. After playing this with the “band” LEDs were a necessity. The Range Master got a Blue on and the Sparkle Boost got an orange. The switches were 3PDT, and so already had the extra pole. The bigger problem here was drilling the box.
I decided to place the knobs on the side of the box. The reasoning being to avoid hitting them with your foot, and provide more real-estate for foot switches. After some use I find this makes the knows hard to read. Might be best to place them on top. Really the settings can all be done by ear. There seems to to also be some peace of mid to be able to look down and read the knobs without testing.
And of course the last mod would be the DC jack. Originally Joe had suggested this, and it wasn’t on my radar, so the build left a few things out. At this stage with everything assembled, the only place for the DC jack is between the knobs. Which is not a bad spot, but poses a potential awkwardness with DC plugs that have a 90 degree connector, like my One Spot. Should still work, and it will give me another excuse to update this blog.