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).
The documentation and the Gerber files for download can be found in my website.
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.
The documentation and the Gerber files for download can be found in my website.
As a Shakuhachi player I need my hands on the flute. So I use me feet to manipulate parameters and switches on the synthesizer. This module was originally build for my Shakuhachi to Synth project to provide the possibility to connect foot switches with the synthesizer and keep the patch intact when they are removed. The signal is not routed through the foot switch. Instead CMOS switches are used, turned on and off with the foot switch. So the signal stays within the synthesizer and the connection to the foot switch carries only DC. Removing the foot switch does not interrupt the signal flow in the synthesizer.
The documentation and the Gerber files for download can be found in my website.
The switch in the DG202 is hold in on position with a 100k resistor against the positive rail. With a foot switch attached you can pull down the hold voltage when you close the foot switch.
This is my first step into the quad world. I want to build a system capable to deal with 4 channels. The tone control is derived from “Small Signal Audio Design” by Douglas Self second edition chapter 15. The maximum output volume is adjustable to protect your PA. You can connect the output directly to active monitors.
The documentation and the Gerber files for download can be found in my website.
A detailed description can be found in “Small Signal Audio Design” by Douglas Self second edition chapter 15.
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
The documentation and the Gerber files for download can be found in my website.
Simple dual amplifier with opamp-array (multipath amplifier).
This module is thought for sending and receiving audio signals. I use it to add some external effects to my modular. Albeit simple, it is very useful. For connecting pedals and external CV sources I recommend my Pedal/CV Send and Receive module.
The documentation and the Gerber files for download can be found in my website.
The outgoing signal is attenuated 1:4 with IC1B. P1 sets the output signal level. The incoming signal is amplified 1:7 with IC1D. P2 sets the input signal level.
As a wind player I need to keep my hands on the wind instrument. This module was first thought for connecting pedals to my modular for changing control voltages. But it is useful to include external signal changers like echo or delay or any other sound and CV source as well.
The documentation and the Gerber files for download can be found in my website.
I think you need no description here.
This module is needed for easy connecting a banana system to a 3.5 eurorack system. It is a passive module. No signal changes are made.
The documentation and the Gerber files for download can be found in my website.
I think you need no description here.
Output Module: Front view
This is my replacement of the original Elektor Formant COM module. I discarded the original circuitry because of the TL085 used with his unusual pinout and the availability of dedicated audio operational amplifiers. I used a more effective filter implementation for tone control. The tone control is derived from “Small Signal Audio Design” by Douglas Self Chapter 15. A optional level indicator makes it easier to find the right volume level for best SNR. The maximum output volume is adjustable to protect your PA. You can connect the output directly to active monitors.
Specs and features
• Bass, middle, treble tone control
• Adjustable maximum output volume
• Optional volume indicator
• Direct connection to active monitors
• Runs on +/-15V and +/-12V (with minor resistor changes)
The documentation for download can be found in my website.
Output Module: Schematic front PCB
Output Module: Schematic back PCB
A description can be found in “Small Signal Audio Design” by Douglas Self Chapter 15
Output Module: Stuffed PCB back view
Output Module: Stuffed PCB side view
Output Module: Side view
Microphone Preamplifier
I needed a microphone preamplifier for my Shakuhachi 2 Synth project. So i build one. The schematic follows the circuitry given in the data sheet of the SSM2019. Nothing fancy. A optional volume indicator is added. I didn’t bother with phantom power. I already have a external unit and didn’t want to go into the trouble designing something. It is on my list for future versions.
Specs and features
Simple microphone preamplifier
Optional volume indicator
Runs on +/-15V and +/-12V
The documentation for download can be found in my website.
Microphone Preamplifier schematic
The schematic follows the circuitry given in the data sheet of the SSM2019. Nothing fancy. A optional volume indicator is added.
Microphone Preamplifier populated PCB
Microphone Preamplifier back