ACXSynth MIDI2CV Firmware v5.7.2

New version of alternative firmware for ACXSynth MIDI2CV has been released. Changes:

  • 8-voice polyphony and polyphonic velocity are now supported. You must have two or more units connected via MIDI-splitter in order to receive identical data. See MIDI Implementation for details.
  • Polyphonic and Monophonic modes now have individual sets of function keys. Store function key is now accessible in any of these modes. See MIDI Implementation for details.

New version can be downloaded on the Project page

Thanks to all donators!

ESI Gigaport HD DC-Coupling Mod

There is number of DAW-sequencer plug-ins that can work with control voltages. For example:  Expert Sleepers Silent Way and M.O.T.U. Volta. Also, any specific CV source can be made with SynthEdit, SynthMaker, Pure Data, Max/MSP etc. In order to output CV to a hardware, an audio-interface with DC-coupled analog outputs is required. (Audio-interface should work correctly with direct current) Most of today’s audio-interfaces have protecting HP filters, placed right before analog outputs. These filters let only alternating current to be passed trough (outputs are AC-coupled) and also provide good dynamic range. Few old professional interfaces (MOTU 828 and others) has DC-coupled outputs. Also, Expert Sleepers has the whole range of specialized audio-interfaces and DACs with DC-coupled outputs. These are good interfaces, but a bit expensive.

The ESI Gigaport HD is known as inexpensive, multichannel 24/96-ready USB audio-interface. Out of the box this interface has AC-coupled outputs but circuit can be easily modified to support CV.

ESI Gigaport HD DC-Coupling: CapacitorsThere is eight electrolytic capacitors inside the device: C36, C41, C46…C71 (marked red). All we have to do is to short capacitor’s terminals together. The first option is to solder a jumper wires around each cap. The second option is to insert switches that could toggle DC- or AC-coupling for individual outputs.
ESI Gigaport HD DC-Coupling: Schematic

Finally we got an interface that supports both CV and audio.

Measured specifications

  • Channel number: 8
  • Amplitude: 6v p-p max. (−3…+3 volts)
  • Maximal positive sample value (32767 или 8388607) inverts (Version 3 drivers)!
  • Channel DC cross-talk: <0.03% (<146dB)

Use carefully! Unprotected inputs/outputs are sensitive to low-impedance current sources. Inaccurate connection may cause damage to interface or degrade it’s specs.

SSSR Labs Lissajous Suite

The new subsection is just open on the site: VST-plugins! This subsection contains free VST-plugins by Dmitry Shtatnov made under his brand SSSR Labs. (Solid State Sound Research Labs.). The first plug-ins suite is just uploaded.

Lissajous Suite Logo

Lissajous Suite is a set of VST plug-ins intended for experiments with the graphical representation of the waveforms on an oscilloscope. This media experiment genre is known as Lissajous music.

Some demonstration videos will appear later. The first one shows features of the MIDIHarmonics VST instrument.

L-1 modules

l-1_logoBelarusian electronics designer Alexey Laman manufactures Eurorack modules under L-1 trademark. His modules are highlighted both by himself and by community members as top-quality modules comparable to Cwejman products. The Company is founded in 2012. Today’s model range includes several dynamic effects (compressor, VCA, mixers), VCF and even vocoder! Modules can be purchased as fully-assembled units or as DIY-kits. In this review I’m going to introduce three L-1 modules at once: 2180VCF, Quad VCA/Mixer and Tube VCA. Continue reading

ACXSynth MIDI2CV Firmware v5.7

New version of alternative firmware for ACXSynth MIDI2CV has been released. Changes (from v. 5.5):

  • Pitch bend now works in all modes.
  • Aftertouch assignable to CV2 Out.
  • 2-voice Split mode at Channel +4 in Multitimbral mode.
  • 2-voice Intellectual duophonic mode at channel +5 in Multitimbral mode.
  • Fixed bug with Voice two acting as Trigger in polyphonic mode.
  • MIDI Clock Rate is now adjustable
  • Version display at startup (0101.0111)
  • Parameters can be stored into EEPROM

The first key pressed at Split mode channel defines split point (the most lower key of the upper zone). Lower zone goes to voice 1 and upper zone goes to voice 2. Split point is set each time when multitimbral mode is selected. Intellectual duophonic mode can be used with two identical voices. Converter analyzes each newly pressed key and assigns corresponding note to particular voice where most closer note was taken previously. This makes it possible to play douphonic parts with glide with no unwanted slew between the parts if there is sufficient space between the hands. This mode doesn’t require fixed split point, but there is no binding between voices and parts like in the split mode. When monophonic part is played, only one voice will be used, there is no unison! New version can be downloaded on the Project page

Thanks to all donators! I mean it, thank you, guys! I’m glad to create as perfect code and design as I can.

AVR Synth 16

avrsynth_picLast time I was telling about one Elby Designs module. So, let’s continue the Australian equipment subject with interesting product manufactured under same brand; AVR Synth. This is the virtual analog synthesizer working on AVR-family microcontroller. The firmware of this synthesizer is written in Assembly language. The code is open-source and schematic is also open. I’m going to tell about the original, 16-bit version and about few forks of this project.

Continue reading

Microtonal Synthesizer

Russian musician-experimentalist Alex Pleninger has been working on this instrument for about a year. The synthesizer consists of three identical blocks. Each of them is based on digital synthesis core. Each core uses two ARM microprocessors. The blocks are controlled with three sensor keyboards: two with 25 keys and one with 50 keys. Capacitive sensors provide only touch sensivity. The scale of each of three blocks can be programmed via control panels. Scale is expressed as index and radicand of the root which determines number of pitches in the octave. Also, the coefficient of the frequency multiplication applied by each successive degree can be manually entered. All of this data is displayed on OLED displays. The instrument also has transpose switch and buttons to select attack and release time. Three sustain pedals can be connected. The interesting detail is that the synthesizer has no MIDI ports at all. (Pleninger is well-known for his hostility to MIDI)
The device is custom-made for one of the famous recording studios.