CatGirl Synth: Difference between revisions

== History ==

[[File:CGS photo jan 2002.jpg|thumb|right|500px|Ken Stone's synth as it was in Jan 2002]]

 

 

== Format ==

 

== Building a DIY synthesizer ==

All electronic projects and designs presented on this web site, or associated web sites should be considered dangerous if not lethal if not used safely. When working on projects based on these designs, use extreme care to ensure that you do not come into contact with mains AC voltages or high voltage DC. If you are not confident about working with mains voltages, or high voltages, or you are not legally allowed to work with mains voltages, or high voltages, you are advised not to attempt work on them. The author, host, and all people associated with these web pages disclaim any liability for damages should anyone be killed or injured while working on these projects, or projects based on these designs, or any other project or design presented on these web pages and any associated web pages. The author, host, and all people associated with these web pages also disclaim any liability for projects, or projects based on these designs, or any other project or design presented on these web pages and any associated web pages when used in such a way as to infringe relevant government regulations and by-laws.<ref name="help"/>

 

 

CGS includes adaptations of several classic [[Serge Modular Music System|Serge]] modules from the [[People's Synthesizer]]. These have been done with the permission and collaboration of [[Serge Tcherepnin]] himself.

 

 

=== CV processors ===

:Is three stages in length, duplicating the functionality of the Serge ASR, but doing it in a very different way. It is great for producing "arabesque-like" sequences, trills etc., when used with VCOs. Of course it's use is not limited to VCOs only.

* <!-- cgs98_busdriver.html -->CGS98 [[CGS bus driver|Bus Driver]]

* <!-- cgs43_cascade_mixer.html -->CGS43 [[CGS cascade mixer|Cascade Mixer]]

:The Cascade Mixer is an experimental mixer that can be built in one of several ways - a unity gain cascaded mixer, a binary weighted (or scaled) mixer, or as a staircase generator when coupled with a [[binary counter]].

* <!-- cgs23_cv_mega_mixer.html -->CGS23 [[CGS CV mega mixer|CV Mega Mixer]]

:This module is an enhanced version of the DC mixer designed for both audio and CV mixing. It has both non-inverting (adding) and inverting (subtracting) inputs, as well as a master level control. It also features two inverting outputs, one that is offset by the master level control, and the other which has independent offset and center inputs.

:Mix synthesizer level audio signals or control voltages with this DC coupled mixer.

* <!-- cgs70_mix.html -->CGS70 [[CGS dev-mod mixer/inverter block|Dev-mod Mixer/Inverter block]]

:The matrix mixer is a multiple input, four output bipolar or unipolar DC coupled mixer, for mixing control voltages or audio signals. In cases where you require several different mixes from a common set of signals, this module is ideal. This variant of the matrix mixer is designed for use behind Serge 4U panels.

* <!-- cgs40_modulo_magic.html -->CGS40 [[CGS modulo magic|Modulo Magic]]

* <!-- cgs80_mix.html -->CGS80 [[CGS multi-mixer|Multi-Mixer]]

:This module is a multi-purpose mixer that can be used for both synth-level audio and control voltages. There are eight input channels, each which has AC coupled and DC coupled inputs and a level control, as well as AC and DC coupled outputs.

* <!-- cgs84_peakandtrough.html -->CGS84 [[CGS dual peak and trough|Dual Peak and Trough]]

:This module is a variation on the 1973 Classic Serge Peak and Trough module. It is much like the [[CGS analog logic voltage processor|Analog Logic voltage processor]], though a little less precise. It is presented here for those who want to build themselves a classic Serge.

:The Serge Smooth and Stepped Function Generator (SSG) is s a complex multi-functional module to provide various slew and sample functions

* <!-- cgs88_bds.html -->CGS88 [[CGS Serge triple bi-directional router|Serge Triple Bi-Directional Router]]

* <!-- cgs56_gatecon.html -->CGS56 [[CGS gate converter|Gate Converter]]

:The purpose of the Gate Converter is to turn standard positive gate signals into negative to postitive going gate signal. This is particularly handy when interfacing to other manufacturer's modules that require a zero crossing singal to operate. It can also be used to convert assorted LFO or VCO signals to square or rectangular waves, to extract some form of gate signal from an envelope and so on.

:8x8 switched mixing matrix. Eurorack format.

* <!-- cgs51_wrs.html -->CGS51 [[CGS weighted random switch|Weighted Random Switch]]

:The Diatonic Converter is an adapter for projects such as the Infinite Melody and Gated Comparator, constricting their outputs to the notes of a major or minor diatonic scale instead of the chromatic scale. A single control line selects between major and minor. It can also be used as a stand-alone module when driven from other systhesizer gate events.

* <!-- cgs42_cv_adapter.html -->CGS42 [[CGS gate sequencer CV adapter|Gate Sequencer CV Adapter]]

* <!-- cgs32_infinite_melody.html -->CGS32 [[CGS infinite melody|Infinite Melody]]

:The name of this module is a play on its function. Put simply, it generates a series of semi-random or themed stepped control voltages, or if you prefer, white and pink control voltages. The pink function is probably better known as 1/f.

:The Serge noise module can be built in several ways. In it's simplest form, it contains three basic outputs, white noise, pink noise, and a random voltage suitable for use with sample and hold modules. An optional sample and hold circuit is included on the PCB. Alternatively, the basic version may be coupled with the [[CGS Serge smooth and stepped generator|CGS92 Serge Smooth and Stepped Generator]] to make the Random Voltage Generator module.

* <!-- cgs92_ssg.html -->CGS92 [[CGS Serge smooth and stepped generator|Serge Smooth and Stepped Generator]]

:The Serge Smooth and Stepped Function Generator (SSG) is a complex multi-functional module to provide various slew and sample functions.

* <!-- cgs86_trk.html -->CGS86 [[CGS touch responsive keyboard|Touch Responsive Keyboard]]

* <!-- cgs96_comp.html -->CGS96 [[CGS Serge triple comparator|Serge Triple Comparator]]

:The Serge Triple Comparator consists of three independent functions which are useful in the production of square waves and variable pulse waves. The Comparator reference level can be a time-varying control voltage, a complex audio signal, or a fixed preset voltage. Additionally, the comparators are useful for level detection and for logic decisions based on amplitude. The module also contains a single, non-adjustable, Schmitt trigger.

:A sequencer designed for controlling pulsed or gated events, for rhythm and percussion.

* <!-- cgs24_gatetotrigger.html -->CGS24 [[CGS gate to trigger converter|Gate to Trigger Converter]]

* <!-- cgs22v2_master_divider.html -->CGS22 [[CGS master divider|Master Divider]]

:The purpose of this module is to divide down a system master clock (e.g. a VCLFO) to drive an array of sequencers or other timed events. The different phase outputs are to allow for modules that may trigger from the falling edge of a wave, or to allow for deliberate lagging of an event. It would for example be possible to have two sequencers running from this unit, one at 1/8 of the frequency of the other, their outputs being mixed to give a sequence that changes fundamental pitch each eight notes.

* <!-- cgs54_xor.html -->CGS54 [[CGS XOR/XNOR logic|XOR/XNOR logic]]

:This board is an add-on for the CGS36 Pulse Divider and Boolean Logic module, adding XOR and XNOR funtionality. It can also be used to compare two analog signals, either positive or negative in value.

* <!-- cgs39_quad_gate.html -->CGS39 [[CGS quad logic gate|Quad Logic Gate]]

:The Quad Logic Gate is a very simple module that can be built in one of five flavors : XOR, OR, AND, NOR and NAND. It is a simple way to gain additional control of gate and trigger pulses within a system. It can also be used for some simple signal multiplying. The XOR is well known as a square wave "ring modulator", though interesing effects can also be generated using the other configurations. Each gate has an inbuilt LED to indicate the status of the outputof that gate.

:The slope detector is an event-driven gate/trigger generating device. It monitors a control voltage, and triggers one of three "gate" output dependent on what the control voltage is doing.

* <!-- cgs01_subosc.html -->CGS01 [[CGS sub-oscillator/harmonic sequencer|Sub-Oscillator/Harmonic Sequencer]] and <!-- uni01_subosc.html -->UNI01 [[CGS sub-oscillator/harmonic sequencer (UNI format)|Sub-Oscillator/Harmonic Sequencer (UNI format)]], designed to fit on a 4U Serge style panel.

* <!-- cgs30_bpf.html -->CGS30 [[CGS bandpass filter|Bandpass Filter]]

:A utility bandpass filter for creating artifical instrument resonant cavities etc.

:This is a strange mixture of a VCO and a switched capacitor filter based on the filter presented by Jan Hall in [[Electronotes]]. If you are after something different, this fits the bill. After all, how many filters have a sync input?

* <!-- cgs43_cascade_mixer.html -->CGS43 [[CGS cascade mixer|Cascade Mixer]]

:[[Peter Grenader]]'s Buchla style Low Pass Gate.

* <!-- cgs40_modulo_magic.html -->CGS40 [[CGS modulo magic|Modulo Magic]]

* <!-- cgs90_phaser.html -->CGS90 [[CGS Serge phaser and audio mixers|Serge Phaser and Audio Mixers]]

:This module is a variation on the classic Serge Phaser module. On the PCB are also two AC coupled audio mixers.

* <!-- cgs77_vcf.html -->CGS77 [[CGS Serge 1973 voltage controlled filter|Serge 1973 Voltage Controlled Filter]]

:This is an adaptation of the original Serge VCF from the early "R" series PCBs. Produced under licence from Serge.

* <!-- cgs102_epp.html -->CGS102 [[CGS Serge equal power panner|Serge Equal Power Panner]]

:Serge Equal Power Panner driver. Produced under licence from Serge.

:This module is a "tribute" module, based on the awesome Steiner-Parker Synthacon VCF. Despite not being a big VCF fan this one really appealed to Ken Stone. Its sound is quite unlike the Moog ladder, and has a lot of character.

* <!-- cgs35_euro_vcf.html -->CGS35EURO [[CGS Steiner voltage controlled HP, LP and BP filter Eurorack|Steiner Voltage Controlled HP, LP and BP Filter Eurorack]]

* <!-- cgs28_seq_switch.html -->CGS28 [[CGS sequential switch|Sequential Switch]]

:A basic switching/sequencing module with many uses.

* <!-- cgs09_vcd.html -->CGS09 [[CGS voltage controlled divider|Voltage Controlled Divider]]

:Use this as a timing accessory for sequencers, or with a VCO for frequency trills like those of the old 8-bit computer games. Unilke other voltage controlled dividers, this one preserves the pulse width of the incoming signal.

=== Signal generators ===

* <!-- cgs19_chime.html -->CGS19 [[CGS chime simulator|Chime Simulator]]

:Feed this module with a high frequency from a VCO or DCO for a range of selectable waveforms/tones. ROMs are available that contain 4 or 8 banks of eight waveforms per bank.

=== General and accessories ===

:This is a tiny board allows easy wiring of banana jack multiples.

:A simple PSU for use with modules that don't require a more expensive alternative. This is suitable for the gate sequencer, burst generator, V8 simulator and a number of other CGS projects.

:A PSU suitable for use with both digital or analog modules. It can actually be varied to cover a fair range of voltages. It is suitable for use with Eurorack standard modules or Modcan and MOTM standard modules.

* <!-- cgs124_bread.html -->CGS124 [[CGS breadboard |Breadboard ]]

:This is a PCB based panel primarily intended for prototyping and testing of new designs, although there is nothing to stop it being used in a permanent set-up. Four of these panels will fit side by side, in a standard rack boat. The 8mm holes are suitable for banana sockets and Cliff-style insulated 3.5mm jacks.

* <!-- cgs98_busdriver.html -->CGS98 [[CGS bus driver|Bus Driver]]

* <!-- cgs99_port.html -->CGS99 [[CGS bus expansion port|Bus Expansion Port]]

:The Bus Expansion Port is a simple PCB carrying three 16 pin (2x8) headers, two on one side, and one on the other, it's purpose being to provide connections between the inside and outside of case, for the distribution of Eurorack style power buses, or with CGS93 and CGS98 bus driver as a way to link them between cases.

:A universal DC mixer and/or analog inverter for use in developing custom modules, or as a stand alone DC mixer.

:Methods, and a small board for joining Dev-mod PCBs together.

* <!-- cgs12_displayadapter.html -->CGS12 [[CGS display adapter|Display Adapter]]

:This board was developed to go with the Wavetable project, allowing easy displaying of the bank and wave numbers.

:Eurorack compatible power distribution bus board.

* <!-- cgs69_gtb.html -->CGS69 [[CGS dev-mod gate/trigger block|Dev-mod Gate/Trigger block]]

* <!-- cgs88_bds.html -->CGS88 [[CGS Serge triple bi-directional router|Serge Triple Bi-Directional Router]]

:The Serge Triple Bi-Directional Router is a group of three switches each of which can route one input to either of two outputs, or either of two inputs to one output according to a pulse or control voltage level. It can also be assembled to sequentially route one input to one of four outputs, or one of four inputs to one output.

:This is an external input amplifier with extra provisions so that it can also be used as an effects pedal interface. There are three identical amplifiers on the board.

:It replaces both the CGS60 v1 and the CGS46 stomp box adapters.

:The Stomp Box Adapter has been designed to allow some of the regular CGS modules to be used as guitar effects. It has an integral power supply and provides two channels of amplification to bring guitar signal levels up to those used by synthesizers, and two attenuators to drop them again, post effect. It also provides the essential bypass circuit.</s>

:These mounting rails are a convenient way of mounting CGS PCBs behind a Serge style panel.

* <!-- cgs93_trunk.html -->CGS93 [[CGS trunk lines/multiples|Trunk Lines/Multiples]]

* <!-- cgsad.html -->Adapter [[CGS banana to 3.5mm adapter|Banana to 3.5mm adapter plug]]

:Are your Serge and your Eurorack modules not talking? Try this.

=== Digital synth ===

* <!-- cgs11_da_converter.html -->CGS11 [[CGS D/A converter|D/A Converter]]

* <!-- cgs25_keyscan.html -->CGS25 [[CGS keyboard scanner sub-module|Keyboard Scanner Sub-Module]]

:This board was really developed for Ken Stone's own use, to allow his 486 based sequencer to connect to various keyboards.

=== Other original designs ===

* <!-- comparator.html -->[[CGS gated comparator]]

* <!-- organ_interface.html -->[[CGS organ interface]]

* <!-- v8sim.html -->[[CGS V8 and diesel simulators]]

=== Tube modules ===

* <!-- 6bn6.html -->[[CGS beam modulator]]

 

== See also ==

* [[CGS parts FAQ]]

 

== References ==

 

== External links ==

* [http://electro-music.com/forum/index.php?f=165 Ken Stone designs - CGS] forum at electro-music.com

 

=== PCBs, kits and ready made CGS modules ===

* [http://www.elby-designs.com/ Elby-designs.com] - Kits and PCBS, CGS in [[Eurorack]] format.

* [http://www.modularaddict.com/ Modular Addict] - Kits and PCBS, CGS in [[Eurorack]] format.

* [https://synthcube.com/cart/ Synthcube.com] - Stocks some CGS PCBS and kits, (has taken over [[Bridechamber]]).