Bleep Sound modules

Following the links below will take you to the module details. Pay attention to the symbols to see if the project is finished or not.

Not all projects are finished or even perfect, use at your own risks.

Filters

• MS20-VCF
  • MS-20 clones built around the LM13700 chip
  • Simple MS20 VCF:
    • 1 LM13700 filter with a Low pass or High pass switch with CV for cutoff
    • Based on barton’s version : (link)
  • Double MS20-VCF
    • 2 filters in one, each with Low pass or High pass with a possibility to bridge them and get a band pass filter with CV for cutoff
    • Based on barton’s version (link)

Mixers

• Basic DC mixer
  • 4 channel active mixer with mute option with DC coupling (Audio+CV)

Multiple

• 3x2 multiple
  • 3x2 passive multiple (3 inputs to 2 output each)
  • cascade the first input to all outputs if no other input is plugged in

VCOs

• RP2040 chord VCO
  • VCO clone, originally made by HAGIWO (link in japanese)
  • RP2040 chord VCO clone in SMD.
  • 5-polyphonic Chord VCO module. There are 8 types of tones. With a built-in quantizer and automatic harmonics function, if you input a suitable CV, it will play a nice chord progression.
• CD40106-VCO
  • CD40106 saw core oscillator based on Moritz Klein version (https://www.ericasynths.lv/shop/diy-kits-1/edu-diy-vco/)
    • 4 waveforms
      • Saw
      • Square with PWM control
      • Triangle
      • Sine
    • 5 octave switch
    • 1v/oct CV, FM CV and PWM CV.
    • Sync input
    • Extender pins to future Sub octave extender

ADSRs

• Basic ADSR
  • Basic ADSR based on René Schmitz Fastest envelope in the West
  • All you need in an ADSR
  • Switch to have 2 different time constants for the ADSR

Power delivery

• Distribution board
  • Basic Eurorack PSU distribution board, with 12 IDC headers.
• USB distribution board
  • Double USB receptacle to power 5V usb devices out of your eurorack case.

Symbol	Description
	Fully designed, debugged, tested, and verified.
	Fully designed but not tested. There is a high chance this won’t work first try.
	Unfinished, messy design. Do not use, for reference or otherwise.

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