I think it was nearly 5 years ago when I originally built my Oakley Sound Systems TM3030 – his take on the TB-303 minus the sequencer. For many years it’s been used with the controls on a ‘temporary’ bit of perspex bolted to the PCB.

While the sound of the unit is close to the 303, it’s not a 303 – not that that bothers me. Because of this I decided to max it out with modifications. Some the classic mods to be found on the internet and some of my own design.

A few friends have asked for a demo of how it sounds so I shot this quick video for anyone daring enough to subject themselves to 8 minutes of the same pattern with a bit of knob twiddling!

Just for the sake of it here’s a series of photo’s charting the finishing off of this build.

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A little while ago while having a bit of a sort out I came face to face with the extent of my backlog of projects! So, I’ve been on a bit of a mission to make a bit of a dent in it.
Here’s my progress so far… (part 1)!

Multi Voice Changer Megaphone

This was an easy one. It’s a cheap and cheerful kids toy I was given as a gift at some point which makes a pretty great noise. Years ago I started experimenting with putting a jack in the side to take a signal straight out for recording purposes. To this end I knocked up a simple opamp gain stage to boost the signal to a better level.

The unit originally worked by a basic trigger switch connecting power to the unit every time you wanted to speak into it. This generated a pretty load pop so I installed a switch for the power and a good quality pushbutton switch to switch on the microphone when you wanted to talk into it. It still pops a little but not that load and I quite like it!

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Finally got round to finishing this filter and I’m very glad I have. It sounds fantastic.

I got the PCB quite a while ago when I swapped some of my boards with another user on Muffwigglers. Initially it didn’t work and it took me a little while to find the error on the PCB which was easily fixed with a jumper wire. I also decided to try it with my replacement for the LM3046 which is discontinued in a through hole package. My replacement uses 3 pairs of SMD matched transistors. I tested it with a real LM3046 and my replacement. There’s more gain in the LM3046 and the signal is a bit hotter but it still sounds pretty much the same with my replacement. As my stocks of LM3046’s are pretty low I decided to use the replacement. I’ve put a link to the project at the end of this post.

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In the video I have one VCO running into the audio input and one into the cutoff frequency CV input. Additional tones are produced by increasing the resonance.

Link to my LM3046 replacement:

Order from OSH Park

So, I was telling a friend that while working on something in my studio I’d been playing with putting my TR-707 drum machine through the Flights of Harmony Plague Bearer. As he was curious to how it sounded I made this little video.

The Plague Bearer is from the DIY run that Flight ran through the Muffwiggler site. I ordered and built 2 for enhanced sound mutilation and I’m still not sure I don’t need 4!!!

So I moved to Bristol in September. Really glad it over as I don’t like moving and I have a lot of stuff!

Shouldn’t complain though as I now have a lot more room. I’ve now got 2 benches – one for studio/music/computer stuff and a second dedicated workbench for electronic designing and building. Oh the simple pleasure of having a space where you can leave that work in progress and come back to it another day!

I also now have a view from both my desks out over the River Avon and Spike Island the other side. A vast inprovement over the wall in my last flat.