Browsing through the Elektor magazine my brother found an interesting tone control based on Sony IC, but it was impossible for us to find this IC in any of the component shops we know of. We then found a very similar Sony IC the TDA7439, and this IC also gave opportunity to control the mid range band as a bonus.
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This is the finished jog wheel pcb. We use a jog wheel with 15 pulses pr. 360° and a push button.