Rampart - Arduino synth explorer built version

Rampart, finished build for those who don't wish to solder. Why not??? :smiley:

By default rampart ships with a bytebeat synth with about 60 formulas. Three categories: rythmical, musical, noisy. But, the all tend to be noisy! But, let me know, and I can flash you another firmware (see below).

Update: May 30, 2025. To celebrate one year of tonetoys, I've released 2 new firmware files:

Dual lfo firmware: A dual lfo with 22 waveforms. output on pins 9/10 (timer1) and ...

A 3synths sketch:

Chord synth

FM synth

shepard tone synth

The binaries can be installed directly with the web based flasher from if you have chrome or edge.

Rampart is designed to allow you to build synths that can be controlled with CV input or produce CV. It has audio/clk input and output, the input being pocket operator compatible. The kit includes a lgt8f328p which has slightly better features than the original Arduino Nano.

Videos of it in action can be seen on the tonetoys site at poetaster.org/rampart .

The default bytebeat synth can, of course, also be modulated by CV input. So, connect a bastl' kastle and have it modulate one of the 3 parameters of the rampart.

Why? Experiment without breadboard.

Don't get me wrong, I use breadboard a lot. But I keep running out of space :) That's why I made Rampart.

I've been making the original variant for years as a means to creating small synths to interact with other small synths like bastl's Kastle. And of course, my own Keep.

All of the Hardware and Software is open source.

The synth has the following parts:

- lgt8f328p compatible with the Arduino Nano, program with Arduino IDE

- 3 pots, adc

- 1 encoder w/button

- 1 analog filter/volume pot

- 5 Pot Knobs

- 2 buttons

- 1 LED

- tactile switch w/LED

- header for a SSD1306 display (display not included)

- audio/clock in, pocket operator compatible

- audio out(wired stereo for headphones)

- Custom female headers - 2 pins - 10 pins

- four rubber feet to bolt on, most important

- 12 mini jumper cables of various lengths and color (no pictured but included)

Firmware, see github.poetaster/rampart

There you will find:

- A dual waveform lfo module

- A 3 synth Mozzi sketch (FM, Chord Synth, Shepard tone synth)

- Several Mozzi based synths, always WIP. FM, Wavepacket and PD resonant voices.

- A bytebeat synth with CV inputs and more than 60 formulas.

- A number of other non-mozzi synth examples.

The firmware can be updated using a web browser (chrome only, any OS). See the poetaster.org page.

#USA

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Due to the new U.S. customs regulations, sending gifts valued over $100 or commercial goods via regular postal mail is no longer possible until further notice. In such cases, both private and business senders can use DHL Express via the DHL online postage service for shipping. You can find official U.S. government information on the background of these changes here (Executive Order) and here (Fact Sheet).