eje Filter Mark 1

Here's a new one. Our user eje posted his filter design on the request section of the forum and asked us to draw a layout for it. The frequency graphs show that it cuts about 5db in 100-200hz range, peaks for +7db at ~2.5khz and cuts everything off from 500khz up. Cuts and boosts of 5-10db will make a difference, so this circuit may be very useful as addition to many dirt circuits - and why not just for getting a custom tone for your clean. I added polarity protection (1N5817 diode) and ripple filter caps for both, the main power supply and vref network. All the rest is eje's handwriting :) So here you guys go: