Eurorack Synth Modules

Overview

• Land Boards Eurorack Modules

ER-ADSR-555-01 - Eurorack ADSR Module

ER-ADSR-555-01

• Attack-Delay-Sustain-Release Eurorack ADSR Module
• 555 Based design
• Benjie Jiao MiniADSR
  • Original was based on Barry Klein design
  • As built by schmitzbits design - "The Fastest Envelope in the West"
  • A, D, and R Pots should be log pots
• Pot silkscreen should show DECAY not DELAY

ER-CV-POTS-5

• Provides 5 Control Voltage Pots for manual control and testing of CV inputs
• Use SYNTH-MIXER6-01 card with rework
  • Do not install Opamp
  • Do not install any passives
  • Clip J2-J7 tip switch pins (edge of card) - verify grounds removed
  • Hacksaw off top of card - J1-J2, RV1-RV2
  • Cut etches from J3-J6 (tip) to RV3-RV6 (bottom pin)
  • Add wires J3-J7 (tips) to RV3-RV7 (center pins)
  • Add wire U1-7 to U1-2
  • Fill holes J8 pins 1,2
  • Install 2x4 header in J8 (pins 3-10)
  • P-Touch labels
    • Label over top 2 holes "CV-POTS-5"
    • Relabel next 5 holes as CV1-CV5
      • Blank label over bottom 2 holes
    • Label end of J8 "CV+"
• Re-build as 4 channels on ER-PROTO-01
  • Buffer outputs with Op Amps
• Could power from either 5V or +/-12V

ER-MIDI-CV4-01 - Eurorack 4X CV Module

ER-MIDI-CV4-01

• Eurorack 6HP, 3U module
• Adapted from HAGIWO's MIDI to CV module
  • Translate from Japanese to English using browser
  • Removes Digital Outputs
  • Has 4 Analog Outputs instead of 2
• Based also on SYNTH-MIDI-CV4-01
• XAIO RP2040 CPU
  • Arduino MIDI library has not yet been ported to Pico so will need to use CircuitPython
• MIDI In on TRS Type A jack
• (4) 0-5V Analog CV outs
  • MCP4822 12-bit D/A - SPI Interface
    • MCP4822 Datasheet
  • Use with SYNTH-VCO-01
    • CV_1 = V/OCT
    • CV_2 = MOD
• Standard EuroRack 16 pin header

ER-MIDI-THRU - Eurorack MIDI Thru

ER-MIDI-THRU

• MIDI In on DIN-5 or 3.5mm TRS Type A
• 4 Channel MIDI outputs on 3.5mm TRS Type A
• Activity LED
• 6 HP wide (30mm)
• 3U tall
• Eurorack power jack
  • Uses 5V

ER-MIXER5-01 - Eurorack 5 Channel Mixer

• ER-MIXER5-01
• Eurorack 6HP
• Adapted from HAGIWO's 5 Channel Mixer Module
• Separate individual input pots and output pot
• Use A taper pots to mix audio signals
• Use B taper pots to mix control voltage signals
• Views: Front Panel, Front (controls), Parts side

SYNTH-MIXER6-01 - Eurorack 6 Channel Mixer

• SYNTH-MIXER6-01
• Eurorack 6HP
• Adapted from HAGIWO's 5 Channel Mixer Module
• Rear card is too tall to fit in rack between rail
• Hacksaw off top of card - remove J1, J2, RV1, RV2 to make 4 in mixer
  • Too tight at the bottom, need to hack off J2, RV2
• Move up holes when mounting card to panel
• Views: Front (controls), Parts side, Front Panel

ER-PROTO-01

ER-PROTO-01

• Eurorack Prototyping card set
• 6 HP wide (30mm) front panel
• 3U tall
• 0-6 POTS
  • Series resistors on pot wiper
  • All 3 pot pins brought to top header
• 0-4 Jacks
• Tip/sleeve brought to header near middle/bottom
• Pots on top, jacks on bottom
  • Easier to adjust pots without bumping into pots
  • Pots more often accessed than jacks
• Large prototyping area
• +12V, -12V down board edges
• 5V/GND down center of card
• Bussed connections horizontally
• Front Panel with generic labels
  • Cover with White on Black P-Touch labels

ER-VCA2-01 - 2 Channel Voltage Controlled Amplifier

• ER-VCA2-01

• Dual VCA
• Adjust between VCA and Mod
• 3U tall
• 6HP wide
• 3 card set
• LM13700 based
• Eurorack
• +/- 12V Power, 10-pin power connector

ER-VCF-01 - Voltage Controlled Filter

ER-VCF-01

• 3U tall
• 6 HP (30mm) wide
• Uses ER-PROTO Front Panel and controls cards
  • Re-label jacks using P-Touch labels
• Tommy Killander Design
  • Low pass only version of Moritz design
• Video

ER-VCO-03 - Eurorack RP2040 VCO

• ER-VCO-03
• Eurorack 6HP
• (3) Card set
• Views: Control Panel rear side, Control Panel controls side, Logic card component side, Logic card rear side, Front Panel

Eurorack +/- 12V Power Supply

• 115VAC in, 24V CT, 24 VA Transformer
  • 12*1.414 = ~17V
    • Leaves 5V for regulator headroom and ripple
• L7812CV, +12V, 1.5A Regulator
• L7912CV, -12V, 1.5A Regulator

Eurorack DIY Panel

• Front/Back View
• Left = top

• Based on HAGIWO design

• 6HP wide
• 3U tall
• Power and Ground bus on either side of the card
• Reduces wiring
• Slotted mounting holes
• 5mm Grid on rear side makes it easier to locate connectors for drilling