Archive for the ‘The Thing That Ate James…’ Category

Last night I finished the A/B switcher I was making for a mate who plays bass. It has 2 channels (obviously!) with a selectable level for each channel. Levels can be toggled between active and passive, when in active mode there is a gain of around x6 right up, which is pretty intense and possibly a bit much. The active mode works pretty sweetly, but it is nice to have the passive option, where the volume only cuts, so that you can use the pedal with no power, or if you don’t fancy passive mode. So you do need to set the dials differently for both options  – in passive mode you would cut the louder instrument to match the quieter, where as in active mode you would probably boost the quieter instrument to match the louder, but it is pretty useful and is generally a set and forget control.

I also added a LDR cut control (‘Suck’) which can be used for small swells and cuts, just for shits and giggles. It is pretty funky and just adds that something to the pedal that others lack. The LDR can be taken out of the circuit with the ‘Suck’ toggle. Housing the LDR itself in a 5mm bezel mount is a much neater way rather than the peep-hole with perspex window I have tried before.

I used a blue/red bi-colour LED to indicate the channel, which matches the red and blue knobs on the levels. Really simple idea, but makes channel identification a no-brainer! I’m really surprised I haven’t seen this on an A/B box before, it just makes sooo much sense!

Anyway here she is:


Quick update, enclosures nearly finished for the next 3 pedals, populating next week…

Wow, it’s been a busy week. I have made up circuits for the 072 buffer, Solar Lifeforce LDR volume/expression pedal and the Divide By Zero feedback loop, and also started making an active/passive A/B box that also has an LDR volume eye for a friend of mine who plays bass! It’s going to be quite a cool little device actually, being able to switch between active and passive is last-minute feature that is going to be pretty neat. I named it “The Thing That Ate James” and re-used the leech graphics that were redundant after “The Leech” became the Bomb Idea. It’s a pretty strange name to be honest, but it comes from the compilation “The Thing That Ate Floyd”, which happened to be on my mind when I was thinking about the pedal. The guy it’s for is called James, so go figure the rest. The pre-amp section of the pedal is TL072 op-amp based, and has a gain of a little over x 2.  The eye (which will work the same as the eye from the Solar Lifeforce, just without a range control) is a bit of an after thought to make it that bit cooler. As it is going to be used as a stage pedal it will really put the LDR to test in that environment.

Anyway, here’s the artwork!

Here’s the album cover to The Thing That Ate Floyd…