Active Slider Bank (command one)

Command one: Front view
Command one: Front view

This utility module gives you a wide range of variable and adjustable control voltages from -10V to +10V. This only depends on the knob and slider setting and patching within itself. If used with external input it can attenuate and offset the incoming signal. I use this module for steering modules which lacks of attenuator at the inputs or in greater patches for applying control voltages to far away modules. It is quite comfortable to have the controls in the first row of your case and not somewhere in the messy patch hardly in reach for your hands

Specs and features

  • Variable and adjustable control voltages from -10V to +10V
  • Six independent active attenuator with external signals
  • Positive and negative offset for external signals
  • Runs on +/-12V and +/-15V
  • Power consumption below 20mA each rail

The documentation and the Gerber files for download can be found in my website.

Command one: Schematic control board
Command one: Schematic control board
Command one: Schematic main board
Command one: Schematic main board
Command one: Populated control PCB
Command one: Populated control PCB
Command one: Populated control PCB back
Command one: Populated control PCB back
Command one: Populated main PCB
Command one: Populated main PCB
Command one: Back view
Command one: Back view
Command one: Side view
Command one: Side view

Logic II (AND, OR, XOR, NOT)

Logic II: Front view
Logic II: Front view

This logic module takes up to four input signals and outputs the logic function AND, OR, XOR dependent on the input signals. The inputs are normalized so you can use less then the four inputs. It has three NOT functions as well.

Specs and features

  • Up to four input signals
  • AND, OR, XOR parallel out
  • Three NOT functions
  • Runs on +/-12V and +/-15V
  • Power consumption below 30mA positive rail. 5mA negative rail.

The documentation and the Gerber files for download can be found in my website.

Logic II: Control board schematic
Logic II: Control board schematic
Logic II: Main board schematic
Logic II: Main board schematic
Logic II: Populated control board
Logic II: Populated control board
Logic II: Populated main board
Logic II: Populated main board
Logic II: Back view
Logic II: Back view
Logic II: Half front view
Logic II: Half front view
Logic II: Side view
Logic II: Side view

Active Attenuator / Amplifier 0–N

Attenuator / Amplifier 0..N: Front view
Attenuator / Amplifier 0..N: Front view

While working with modulars I have had some modules lacking input attenuator or output volume. To cure that I have build this module. It is usable as active attenuator and / or amplifier. The attenuation or amplification is determined by one resistor per channel, so you can easily adjust the attenuation or amplification to your needs.

Specs and features

  • Three independent active attenuator or amplifier
  • Attenuation / amplification adjusted with one resistor.
  • Runs on +/-12V and +/-15V
  • Power consumption below 20mA each rail

The documentation and the Gerber files for download can be found in my website.

Attenuator / Amplifier 0..N: Schematic
Attenuator / Amplifier 0..N: Schematic

The attenuation or amplification is determined by one resistor per Channel (R2, R7, R12)

Attenuator / Amplifier 0..N: Populated PCB
Attenuator / Amplifier 0..N: Populated PCB
Attenuator / Amplifier 0..N: Back view
Attenuator / Amplifier 0..N: Back view
Attenuator / Amplifier 0..N: Side view
Attenuator / Amplifier 0..N: Side view

Logic I

Logic I:Front view

This logic module takes up to four input signals and outputs the logic function AND, OR, XOR dependent on the input signals. The inputs are normalized so you can use less then the four inputs.

Specs and features

  • Up to four input signals
  • AND, OR, XOR parallel out
  • Runs on +/-12V and +/-15V
  • Power consumption below 30mA positive rail. 5mA negative rail.

The documentation and the Gerber files for download can be found in my website.

Logic I: Schematic control board
Logic I: Schematic control board
Logic I: Schematic main board
Logic I: Schematic main board

Nothing special to mention. On page one you see the input and outputs. On page two are the input protection circuitry, the microprocessor and the output buffers. The logic is done in software.

Logic I: Populated control board
Logic I: Populated control board
Logic I: Populated main board
Logic I: Populated main board
Logic I: Back view
Logic I: Back view
Logic I: Side view
Logic I: Side view

Quad Ringmodulator

Quad Ringmodulator: Front view
Quad Ringmodulator: Front view

This is the 12V Euro version of my NGF dual version. It uses the now obsolete LM1496 balanced modulator -demodulator. But you can still source them and I have some in my stock. So I decided to make a PCB and module. I started with the original Elektor Formant schematic published in “Formant Erweiterungen” p35ff. I left out the microphone and envelope follower part because I already have such modules. I have added input buffers and raised the signal level to my 10Vpp used throughout my system.

Specs and features

  • Quad Ringmodulator
  • 10Vpp input and output
  • Runs on +/-12V and +/-15V
  • Power consumption around 70mA each rail

The documentation and the Gerber files for download can be found in my website.

Quad Ringmodulator: Schematic control board
Quad Ringmodulator: Schematic control board
Quad Ringmodulator: Schematic main board
Quad Ringmodulator: Schematic main board
Quad Ringmodulator: Populated control PCB
Quad Ringmodulator: Populated control PCB
Quad Ringmodulator: Populated main PCB
Quad Ringmodulator: Populated main PCB
Quad Ringmodulator: Back view
Quad Ringmodulator: Back view
Quad Ringmodulator: Side view
Quad Ringmodulator: Side view

Stereo Mixer

Stereo Mixer:Front view
Stereo Mixer:Front view

This is a 3 in 1 stereo mixer with normalized left to right inputs. The module is DC-coupled and can be used for audio and control voltage mixing.

Specs and features

  • 3 in 1 Stereo mixer
  • Left input normalized to right input
  • DC coupled
  • Power consumption below 20mA each rail

The documentation and the Gerber files for download can be found in my website.

Stereo Mixer: Schematic
Stereo Mixer: Schematic

Nothing special here. Simple, straight forward mixer design.

Stereo Mixer: Populated control PCB
Stereo Mixer: Populated control PCB
Stereo Mixer: Front side view
Stereo Mixer: Front side view
Stereo Mixer: Back view
Stereo Mixer: Back view
Stereo Mixer: Sde view
Stereo Mixer: Sde view

Headphone Amplifier

Headphone Amplifier: Front view
Headphone Amplifier: Front view

Not that much to say here. Simply a Headphone Amplifier. Based on Douglas Self “Small Signal Audio Design” second edition pg.560 and pg.33 fig.1.12

Simple dual amplifier with opamp-array (multipath amplifier).

Specs and features

  • Drives headphones in the range from 50R to 600R
  • Runs on +/-15V and +/-12V
  • Power consumption around 25mA each rail

The documentation and the Gerber files for download can be found in my website.

Headphone Amplifier: Schematic control board
Headphone Amplifier: Schematic control board
Headphone Amplifier: Schematic main board
Headphone Amplifier: Schematic main board
Headphone Amplifier: Populated control PCB
Headphone Amplifier: Populated control PCB
Headphone Amplifier: Populated main PCB
Headphone Amplifier: Back view
Headphone Amplifier: Back view
Headphone Amplifier: Side view
Headphone Amplifier: Side view

Scanning Mixer

Scanning Micer: Front view
Scanning Micer: Front view

This scanning mixer is derived from the work of J├╝rgen Haible and Don Tillman with a lot off additions, changes and expansions.. The mixer is able to scan through four inputs with variable depth ans position. Manually and CV controlled. You can overdrive the individual channel nicely to add some overtones per channel. Rate, depth and scan amount are voltage controllable. The mixing level is controlled with sliders and voltage controllable as well. The four channels are summed into an output channel with similar controls.

The scanning mixer comes in two flavours linear and logarithmic. The linear scan gives a more smooth transition between the channels. The logarithmic scan gives a steeper separation between channels. All channels are DC coupled. So you can get interesting slowly moving CV textures when slowly scanning through different LFO outputs. When the depth potentiometer is set to zero you can use this module as simple voltage controlled mixer

Specs and features

  • Four input channels
  • DC coupled
  • Overdrive per channel
  • Variable scan depth and position
  • Voltage controlled rate, depth and scan amount
  • Mixing level voltage controllable
  • Power consumption below 80mA each rail

The documentation and the Gerber files for download can be found in my website.

There are to much schematic to post here. Please refer to my website. Only pictures here.

Scanning Mixer: Control PCB top
Scanning Mixer: Control PCB top
Scanning Mixer: Control PCB back
Scanning Mixer: Main PCB 01 lin
Scanning Mixer: Main PCB 01 lin
Scanning Mixer: Main PCB 01 log
Scanning Mixer: Main PCB 01 log
Scanning Mixer: Main PCB 02
Scanning Mixer: Main PCB 02
Scanning Mixer: Half front
Scanning Mixer: Half front
Scanning Mixer: Back
Scanning Mixer: Back
Scanning Mixer: Side
Scanning Mixer: Side

Active Case Connector

Active Case Connector: Front view
Active Case Connector: Front view

When using different cases it is quite inconvenient to run lots off long patch cables between them. With this pair of modules you can reduce the amount of patch cables used between cases. This modules allows to use ribbon cables between cases. The connections are active buffered with OpAmps, so they are unidirectional. To connect cases in both directions (send and return) you need two pairs of this modules.

Specs and features

  • Eight active unidirectional connections
  • Runs on +/-12V and +/-15V
  • Power consumption below 20mA each rail

The documentation and the Gerber files for download can be found in my website.

Active Case Connector: Schematic send
Active Case Connector: Schematic send
Active Case Connector: Schematic receive
Active Case Connector: Schematic receive
Active Case Connector: Back view
Active Case Connector: Back view
Active Case Connector: Populated PCB
Active Case Connector: Populated PCB
Active Case Connector: Side view
Active Case Connector: Side view