Studio Electronics Tonestar Folk Eurorack Synth Module (Folktek)

Studio Electronics says...

TONESTAR FOLKTEK is an Arias Blaze / Folktek Fibonacci flight, feast and fancy. We were hyped when Arias told us, "I like your layout - it's very approachable. And you've got some hex things happening which I'm all about" Who knew the Tonestar was so hexy?

ABlaze continued "I'm a circle person so you're going to end up with something that circle driven. The design will end up like a vision. If you're not into that, say the word now..." Oh but we were. He continued—well he wrote this bit before the last, "One of my goals is not just to throw some image stuff on this but to create something that makes sense visually as it corresponds to functionality. I find that kind of thing difficult with complex layouts like this - it's difficult to find the room for pure design, yours or mine. But at this point I'm starting to come to something..."

We think it's quite something and... necessary.

Features

• All Controls—arranged in order of signal flow—and Patch Points
• VCO:
• FREQUENCY – Oscillator frequency attenuator.
• PULSE WIDTH – Variable pulse wave width control.
• OCT – +1/-1 octave switch. 
• LFO (^) – Triangle wave low frequency oscillation to pulse width control.
• FREQ/PW – Oscillator frequency, or Pulse (square wave) width to ADSR modulation routing switch. Center off.
• GLIDE – Slew generator control.
• MOD (ADSR) – Oscillation modulation via ADSR control. 
• TRIANGLE*/NO VCF – Triangle to VCA switch—bypasses VCF. 
• SAWTOOTH* – Sawtooth wave attenuator.
• SQUARE* – Square wave attenuator.
• SUB – Square wave Sub Oscillator attenuator.
• TRIANGLE* – Waveform output.
• SAWTOOTH* – Waveform output.
• SQUARE* – Waveform output.
• MIX – Composite waveform output.
• 1V/O – One volt per octave control voltage input. 
• TUNE – Master fine tune (approx. -5/+ 5 semitones).
• MOD IN – Modulation CV input. Normaled to ADSR; ADSR is replaced when alt. source connected.
• * symbol

Noise:

• NOISE – White noise generator output.
• LEVEL – Noise attenuator.

VCF:

• FREQUENCY Frequency, or cut-off attenuator
• RESONANCE – Resonance, or Q attenuator.
• TRACK – Keyboard/voltage tracking attenuator.
• DRIVE – Oscillator output to filter input attenuator.
• FREQ/RESO – Filter Frequency, or Resonance to LFO modulation routing switch. Center off position.
• ADSR – Filter to ADSR envelope attenuator. 
• MOD (LFO) – Filter to LFO attenuator. 
• EXT IN – External audio input. 
• FIL OUT – Filter audio output. 
• MOD IN – Frequency or Resonance modulation CV input.

LFO:

• TRIANGLE/SQUARE* – Waveform select switch (triangle core).
• DPTH (OSC) – LFO to Oscillator control. 
• SPEED – Speed or rate attenuator. 
• DEPTH – Control voltage Input.
• TRIANGLE* – Triangle wave output.
• SQUARE*– Square wave output. 
• SPEED – Speed or rate CV input.
• * symbol

ENVs:

• ATTACK – Attack stage control.
• DECAY – Decay stage control.
• SUSTAIN – Sustain stage control.
• RELEASE – Release stage control.
• DRONE/MASTER – Indefinite/instant sustain, and master mode for ADSR routing switch: fuses VCF envelope with VCA envelope. Center off.
• ATTACK – Attack stage control
• RELEASE – Release stage control.
• MOD IN – Allows for dynamic modulation of the ADSR, eg., if you want the amount of modulation added to/determined by a external source, jack in; or if you prefer, modulation input to the ADSR routing—use with velocity, or a sequencer: the sequencer could isolate the ADSR amount the amount to a single step in the phrase for example. Exciting. A second external envelope can provide an interesting effect, or the AR (in the box patching).
• ADSR OUT – ADSR output. 
• AR OUT – AR Output.

VCA:

• FEEDBACK – Oscillator/filter feedback loop control.
• VOLUME – Master volume control.
• VCA CV – Amplifier control voltage output.
• IN/MIX – VCA mix input switch switch (normalled jack). When set to IN, external audio replaces filter output to VCA; when set to mix MIX, filter output is fed along with the filter audio to VCA.
• VCA IN – Audio input.
• OUTPUT – Main output.

Vitals

• PCB Mounting Scheme - Through-hole.
• Filter - Discrete, voltage controlled, 24/db/oct cascaded transconductance low-pass filter, employing six pairs of hand-matched transistors.
• Size - 32hp.
• Depth - 35mm including connectors.
• Power Usage - 130mA, 80mA (+12 / -12)