I bought the bare original Soundlab PCB in 2007 as a way of getting a relatively cheap mono synth. I didn’t realize at the time that it was only designed as a noise box and was going to need some major upgrades before it could be used for anything even vaguely recognizable as music.
This was always designed as a real get down and dig DIY project so originally there was no front panel to buy you had to make your own. It was originally designed to be switched, with no patch leads but I could feel that this was far too limiting for and just under the surface was a whole new world waiting to be set free with patch leads.
My first version was built on a old repurposed eurorack panel, and used 4mm banana plugs, but this was constantly being modified and getting tatty so eventually I took the plunge to have a really nice version made from 3mm acrylic, although originally I was going to stick with the 4mm plugs.
12 years and many false starts later I have ended up with this. It is still the same acrylic panel, but I have changed it over to 3.5mm jacks which are now cheaper and work better with my other kit. The main PCB is mounted on an aluminium shelf held in place by 5 of the pots, and the various daughter boards which house the extensions are fixed in place by pots and PCB brackets.
Apart from replacing all the switches with mini jacks the mods from the original include:
- Power converted to +/-12V (from +/-9V)
- LFO: LED, Inverted output, extended low frequency range down to once in 40 seconds
- AR Gen: LED, Inverted output and trig level control
- VCO1: PWM, High frequency compensation, triangle output
- VCO2: High frequency compensation, triangle output
- VCF: Exponential response
- VCA: Exponential response
Most of these are my own mods, but some such as the high frequency compensation and exponential response were clones from other MFOS designs.
The coloured jacks correspond to the colour of the knobs above, red for signal in, blue for primary control in, black for outputs and the others for module specific control inputs. I made them from standard knobicon 3.5mm jacks, refitted with washers and hex nuts from Thonk. The coloured skirts are 0.5mm thick shim washers which were sprayed with an etching primer then coated with various Humbrol sprays. I appreciate that this was a cosmetic indulgence but I really like the look now its done.
Here in 2019 I think it is pretty much complete although ironically I have several others synths now so I tend to only use this for its original purpose, which is a sound box, but hey it was a great background project and by heck does it go well with my Keystep 🙂
Big thumbs up to Ray for giving these designs, the man was a genius and I miss him.
The Paupers Electronic Music Studio 