What? Rampart, DIY synth playground kit.

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.

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)

A 3synths sketch: Chord synth FM synth shepard tone synth

By default rampart ships with a bytebeat synth with about 60 formulas. Three categories: rythmical, musical, noisy. But, the all tend to be noisy! The 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. To build your own you can just use the Fritzing files in the repositories at will :) Or support your dear poetaster :)

Special? Features include:

• lgt8f328p compatible with the Arduino Nano
• 3 pots, adc
• 1 encoder w/button
• 1 analog filter/volume pot
• 5 Pot Knobs
• 2 buttons
• 1 LED
• tactile switch w/LED
• CV inputs (analog)
• header for a SSD1306 display
• 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)

Special? Firmware

• 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.

I've recently implemented a web based flasher so it's really easy to try pre-built firmware: https://poetaster.org/webflasher/

USA

Important! message to buyers in the United States of America. The current administration in the US of A have seen fit to set Tariffs that may amount to 40 % of the price of the article. Nominal rate is 5.4%, which is ok. I can't afford to raise prices while trying to get an automated system (duty paid with shippers) running. That means, ordering from me means you may be charged up to 40% of the cost of the article by the State. Please do NOT order from the US of A unless you are prepared to pay the postal service / gov't there after paying here. I thank you very much for your support to date. Americans have been great customers, supporters and friends. Trump & co. not so much, I guess.