The Ocean project

Posted on Feb 08, 2016 by rutgervlek

I’ve been getting a lot of questions about ‘the synth in the banner’, so it’s time time to reveal the details about this rather special instrument.featured

Roughly 12 years go, after having brought back to life quite a few vintage synths, I felt like building my own instrument. For a year I have been working on the idea, drawing diagrams, searching for parts, and trying various circuits. At that time, I didn’t feel comfortable designing all the electronics myself, so I chose the safe(r) route and decided to use Oakley sound circuit boards for the crucial functions in the audio path.

Since I’m about 50% live performer and about 50% studio nerd, I had special wishes for this new synth. First of all, I was hoping to build a synth with “that” analog sound (the sound on records by Pink Floyd, Yes, ELP, etc). I wanted to have these sounds easily accessible for live use, yet keep the options for more complex studio sound design open. After considering something fully modular, I chose to keep it semi-modular (think Korg MS-20). Internally, all modules (functions) have a default connection, such that you can instantly play them, but also provide access points on a patch panel for more complex routing. Finally, I decided to go with these modules:

  • 3x VCO
  • 3x VCO octave switcher
  • 1x MidiDAC
  • 1x Super Ladder VCF
  • 1x Steiner Synthacon VCF (years before Arturia built it into the MiniBrute…)
  • 2x ADSR/VCA
  • 1x VC-LFO
  • 1x Equinoxe Phaser
  • 1x Ring Modulator
  • 1x dual VCA
  • 2x dual CV mixer
  • 1x sample & hold
  • 1x lag generator
  • 1x noise source (white, pink, IR)
  • 1x Output stage + headphone amp
  • 1x Power distribution board

Some circuit boards were already etched (the Oakley Sound ones), other modules were (re)designed and etched by me. In the pictures below you can see how these boards transformed into the Ocean synth.

A couple of months later the Ocean was announced ‘Keyboard of the month July (2006)’ in the international Keyboard Magazine. Michael Gallant writes: “… the Ocean is one beautiful monster of a keyboard”.

After completion I recorded a short piece of music with a lot of use for the Ocean (all, except drums, mellotron and strings). I apologize for it sounding slightly dated, given modern recording quality standards.

synthdiary12

Working on the layout of the noise module in Eagle PCB.

synthdiary01

Transparent sheet with the Steiner VCF design on it, and a blank UV-sensitive PCB.

synthdiary05

The etched Steiner VCF and ring modulator PCB.

The finished noise and S&H modules sharing a board

The finished noise and S&H modules sharing a board

The three finished VCOs

The three finished VCOs

Backside of a temporary plywood front panel containing a first test setup (L->R): Midi DAC, VCO (in front the second VCO), Octave Switch, Steiner VCF, Output board, Power distribution board.

Backside of a temporary plywood front panel containing a first test setup (L->R): Midi DAC, VCO (in front the second VCO), Octave Switch, Steiner VCF, Output board, Power distribution board.

Working on the casing, using a keyboard cannibalized from an old MIDI controller.

Working on the casing, using a keyboard cannibalized from an old MIDI controller.

Finished casing with mains inlet and fitted pitch/mod wheels.

Finished casing with mains inlet and fitted pitch/mod wheels.

Powering up! The toroidal transformer, 15V regulators and the distribution board.

Powering up! The toroidal transformer, 15V regulators and the distribution board.

All circuitry fitted, just!

All circuitry fitted, just!

All systems go! A finished synth, at last!

All systems go! A finished synth, at last!

The Ocean backstage after an open-air concert at Elsrock 2006.

The Ocean backstage after an open-air concert at Elsrock 2006.