TONESTAR 8106, an ARP® 2600-inspired complete synth voice, infuses Tim Caswell's "" filter alchemy—a 6db/oct hi-pass filter followed by a recreation of the Roland IR3109 module—into our  platform; this chirpy yet full-bodied 8106 model is also fully # modular featuring 27 pots—one more that the 2600 model for the high-pass filter, 6 switches—one less, sacrificing resonance modulation for that high-pass filtering, and 21 jacks. If the ToneäÖÊ 8106 thins somewhat with resonance excess, route the triangle wave 'round the VCF with the "NO VCF" switch setting, and keep this juicy reimagining of the Roland® IR3109 module boomin' and gloomin'. Nearly thrilling  (there). Caswell Knowledge (circuit designer talk): 

"The VCO is the same affair as the Oscillation, the Boomstar, and the Omega. It's kind of a combination of Arp®, Oberheim® and Moog® circuits (sort of a greatest hits), time-tested, very stable—very good tracking over a very large range; certain parts have to be hand selected to achieve that level of exacting performance. Editors Note: This module is a TONESTAR—its own thing—and not a 2600 clone attempt; nevertheless, the ToneäÖÊ tugs lovingly at times on the sleeve of the 1970's era classic.
Envelope FYI: The Tonestar Sustain control replicates the behavior of the 2600 and Odyssey: after the initial Decay, it continues to move (sink) very slowly, adding a little extra texture to the sound. It's technically a flaw, but after digging out my Odyssey, it is for sure a desirable "quirk", and the perfect companion to the 4072 filter (which we mistakenly titled a  in the  line).
Another bit of fun: The LFO is voltage controlled, so you can envelope, LFO, or otherwise modulate both the rate and the depth; the ADSR amount is also voltage controlled, so it can be manipulated by MIDI dynamics, MIDI volume, an LFO, etc. Greg
[St. Regis] has decreed that anything must be patchable to anything, so some technically wrong patchings (for example, pulse wave out to ADSR out) may often produce unexpectedly interesting, x-mod/notch filtering—quite pleasing effects. 
The Tonestar was Greg's concept, but as I understood it, the goal was a single oscillator, 2600 VCF (initially), pre-patched and yet fully modular classic synth voice, at a specific size, wielding every trick we could cram in. Main use would be as a go-to bassline/lead tool, or a premium quality, entry-level, complete synth module, for root-to-leaf sound design, and multiform analog exploration/expression."
Instagram Junp-cut
( ) represents normalled connections. 
27 Knobbed and "Shafted" Potentiometers
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6 Switches
VCO: OCT (up/null/down); FREQ/PW (frequency/null/pulse width); NO VCF (VCF/null/no VCF); VCF:TRIANGLE*/SQUARE* (triangle/null/square); ENVs: HOLD, MSTR (hold/null/master); VCA: IN/MIX
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21 Jacks
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All Controls—arranged in order of signal flow—and Patch Points 
RANGE – Oscillator frequency attenuator. 
PW MAN – 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.
PORTA – Slew generator control.
MOD (ENV) – 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.
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NOISE – White noise generator output.
LEVEL – Noise attenuator.
FREQ - Frequency, or cut-off attenuator.
RESO – Resonance, or Q attenuator.
KYBD – Keyboard/voltage tracking attenuator.
DRIVE – Oscillator output to filter input attenuator.
HPF – High Pass Filter.
ENV – 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.
TRIANGLE/SQUARE* – Waveform select switch (triangle core).
AMNT (OSC) – LFO to Oscillator control. 
RATE – Speed or rate attenuator. 
AMNT – Control voltage Input.
TRIANGLE* – Triangle wave output.
SQUARE*– Square wave output. 
RATE – Speed or rate CV input.
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A – Attack stage control.
D – Decay stage control.
S – Sustain stage control.
R – Release stage control.
HOLD/MSTR – Indefinite/instant sustain; master mode switch for single ADSR: fuses VCF envelope with VCA envelope. Center off.
A – VCA Attack stage control
R – VCA 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.
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. 
PCB Mounting Scheme - Through-hole.
Filter - A 6db/oct hi-pass filter followed by a recreation of the Roland® IR3109 module, which is a 4 pole, 24 db/oct voltage controlled lowpass filter with voltage controlled resonance. 3 dual OTAs with similar topology to the BA662 used in the Jupiter 8 (and the IR3109 module) were employed, 1 amp for the hi-pass filter, 4 (with added buffers) for the low-pass, and 1 for the resonance. This filter takes a wide range of input signals, and tracks control voltage extremely well. Tap points are available for 6db, 12db, and 18db/oct. Although the topology is similar to the 4072, the tonality, especially when over driven, is distinct.
Size - 32hp.
Depth - 35mm including connectors.
Power Usage - 130mA, 80mA (+12 / -12)
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Product Specs

Brand New (New)
Brand New items are sold by an authorized dealer or original builder and include all original packaging.learn more
Brand Studio Electronics
Model TONESTAR 8106
Finish Standard
Categories Eurorack
Year 2017

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Studio Electronics Tonestar 8106 : Eurorack Module : NEW : [DETROIT MODULAR]
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