OVUM user modifications and customizations

Sometimes users modify their OVUM - we love that! Please send photos and details of any mods you've done, so we can share them here and inspire others! Contact us with your OVUM's serial number for a copy of OVUM's circuit schematic.

Table of contents

• Knob caps
• Individual outs

Knob caps

A number of users have modified OVUM to add knob caps, below is some guidance on adding knob caps:

• The knobs OVUM uses are 6mm in diameter. Their total height above the panel is about 11mm (+/- 2mm), with 9mm sticking up from the 6.9mm diameter metal sleeve.

• D-shaft caps do NOT work.

• T18-shaft caps MIGHT work depending on how tight the tolerances are - but if they don’t, and the inside of the cap is plastic, you could probably ream them out a bit with a drill bit to make them work. Just shoving these onto the shafts WILL mangle the plastic.

• There’s about 21.75mm from the center of one pot shaft to the center of it’s nearest neighbour, so pick caps that are 20mm in diameter or less to avoid the knobs interfering with each other.

• The best kind of caps to use are the ones with a set-screw, since they tend to accommodate a bit of a range of shaft sizes. Ones like these, with a 6.35mm shaft-hole work, but they sit ever so slightly off-center which may or may not bother you.

Indivudal outs

A few users have modified their OVUM to allow individual output of each oscillator. This allows you to create complex stereo effects, or apply different effects to each of OVUMs voices.

There are some caveats to individual outs:

• First, the outs have a DC offset. That is, the voltage is between 0-4.5V, rather than centered at 0V and oscillating above and below that point.
• Second, the outputs have a different response curve to the volume sliders - 90% of the slider travel gets you 60% of the volume, the last 10% gets you the other 40%.