video upload by Elektor TV
Elektor J2B Synthesizer First Demo of Prototype from 2014.
"This video shows Elektor's J2B Synthesizer prototype running a soft synthesizer engine ported from the ATmegatron by Soulsby. Listen carefully to the sounds produced by this beast and admire the way you can control it. LPC1347 rulez the waves :-)"
via this auction

The Atmegatron has two rotary encoders, eight potentiometers and a pushbutton. Two potentiometers are for volume and bass boost, the others control the synthesizer itself. The J2B board can have up to nine rotary encoders, or eight plus a pushbutton.
The Atmegatron uses a bunch of bi-color LEDs to interface with the user. The J2B can have an LCD.
The Atmegatron uses PWM to produce its sound, the J2B has excellent PWM capabilities.
Based on the previous observations, porting the Atmegatron to the J2B should not be a huge task, which is why I started doing it. The most daunting task was to replace the analog potentiometers by rotary encoders while keeping the same feel.
Two rotary encoders replicate the Atmegatron encoders, six others simulate the potentiometers. The bi-color LEDs are replaced by a 2x16 LCD, but I added two bi-color LEDs to indicate the red/green modes of the synthesizer.
A cool thing of the J2B is its built-in USB capabilities making it possible to update the firmware from any Windows PC simply by copying a file to the board which is seen as an external drive. No programmer needed at all.
PWM capabilities of the LPC1343 are a bit better than those of the ATmega328, which allowed me to increase the sample frequency and gain a bit, making it a 9-bit synthesizer. So, in theory, the sound quality of the J2B synth should be a little better than the Atmegatron."

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